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  • 51.
    Fu, Qilin
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi. Plasmatrix Materials AB, Sweden.
    Rashid, Md Masud-Ur
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi. Plasmatrix Materials AB, Sweden.
    Nicolescu, Cornel-Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Toth, Geza
    et al.,
    High dynamic stiffness mechanical structures with nanostructured composite coatings deposited by high power impulse magnetron sputtering2016Ingår i: Carbon, ISSN 0008-6223, E-ISSN 1873-3891, Vol. 98, s. 24-33Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Nanostructured Cu:CuCNx composite coatings with high static and dynamic stiffness were synthesized by means of plasma-enhanced chemical vapor deposition (PECVD) combined with high power impulse magnetron sputtering (HiPIMS). Scanning electron microscope (SEM) images and energy-dispersive X-ray spectroscopy (EDS) mapping from cross-sectioned samples reveals a multi-layered nanostructure enriched in Cu, C, N, and O in different ratios. Mechanical properties of the coatings were investigated by Vickers micro-indention and model tests. It was observed that copper inclusions as well as copper interlayers in the CNx matrix can increase mechanical damping by up to 160%. Mechanical properties such as hardness, elastic modulus and loss factor were significantly improved by increasing the discharge power of the sputtering process. Moreover the coatings loss modulus was evaluated on the basis of indentation creep measurements under room temperature. The coating with optimum properties exhibited loss modulus of 2.6 GPa. The composite with the highest damping loss modulus were applied on the clamping region of a milling machining tool to verify their effect in suppressing regenerative tool chatter. The high dynamic stiffness coatings were found to effectively improve the critical stability limit of a milling tool by at least 300%, suggesting a significant increase of the dynamic stiffness.

  • 52.
    Grenmyr, Gustav
    et al.
    Chalmers, Dept Mat & Mfg Technol.
    Berglund, Anders
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Kaminski, Jacek
    Chalmers, Dept Mat & Mfg Technol.
    Nicolescu, Cornel Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Analysis of Tool Wear in CGI Machining2008Ingår i: IMETI 2008: INTERNATIONAL MULTI-CONFERENCE ON ENGINEERING AND TECHNOLOGICAL INNOVATION, VOL I, PROCEEDINGS, 2008, s. 34-39Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this study the tool wear and wear mechanisms on coated cemented carbide inserts were investigated in turning of Compacted Graphite Iron (CGI) materials with different nodularity. Investigation of how small changes in nodularity affect the wear behaviour of inserts in CGI machining has not earlier been done. The inserts were examined in LOM, SEM and in EDX. The tool wear could on the basis of their wear appearance be classified in three different wear categories; A, B and C. In the wear category A, abrasive wear, adhesive wear and delamination wear could be seen. In the wear category B, the predominant wear mechanism was chipping. The wear appearance in wear category C indicated attrition wear and dissolution via diffusion. Classification of the wear mechanisms gave knowledge that could be used in tool design. The results showed that increasing nodularity has impact on wear at moderate and high cutting speed but not at lower cutting speed. Machining of all materials at high cutting speed, 400 m/min, led to complete degradation of the edge line. A small difference in nodularity from 5% to 20% has more significant impact on wear than from 20% to 62%. This seemed to be correlated with the difference in ultimate tensile strength between the materials.

  • 53.
    Grenmyr, Gustav
    et al.
    Chalmers University of Technology, Department of Materials and Manufacturing Technology.
    Berglund, Anders
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Kaminski, Jacek
    Chalmers, Dept Mat & Mfg Technol.
    Nicolescu, Cornel Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Investigation of tool wear mechanisms in CGI machining2011Ingår i: International Journal of Mechatronics and Manufacturing Systems, ISSN 1753-1039, Vol. 4, nr 1, s. 3-18Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this study, the tool wear, including wear mechanisms on coated cemented carbide inserts were investigated in the turning of Compacted Graphite Iron (CGI) materials with varying nodularity. The results showed that increasing nodularity, in the range of 5–62%, affects wear at moderate and high cutting speeds without having the same impact at lower cutting speeds. A small difference in nodularity, in the lower range, such as an increase from 5% to 20%, has a more significant impact on wear than an increase from 20% to 62%.

  • 54.
    Grenmyr, Gustav
    et al.
    Chalmers University of Technology, Department of Materials and Manufacturing Technology.
    Berglund, Anders
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Kamiski, Jacek
    Chalmers University of Technology, Department of Materials and Manufacturing Technology.
    Nicolescu, Cornel Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Analysis of machining Compacted Graphite Iron (CGI) by join Investigation of Tool Temperature, Cutting Force and Tool Wear2008Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this study a systematic approach for understanding the cutting process in CGI machining is be presented. Tool wear, tool temperature, measured with an IR camera,and cutting forces were investigated. CGI material properties were studied and contact zones on the inserts analysed. Quick stop tests were performed and a FEM temperature model, built on both experimental- and modelled data developed. The experimental data were used, both to calibrate and validate the temperature model. The results showed that increasing nodularity led to higher cutting forces and temperature. Increasing nodularity had impact on wear at moderate and high cutting speed but not at lower cutting speed. Classification of the wear mechanisms gave knowledge that could be used for tool design.The results demonstrate the need of complementing the IR camera temperature measurement with modelling to acquire an estimation of the temperatures in the cutting zone.

  • 55.
    Hedlind, Mikael
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Datorsystem för konstruktion och tillverkning.
    Lundgren, Magnus
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Datorsystem för konstruktion och tillverkning.
    Archenti, Andreas
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Kjellberg, Torsten
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Datorsystem för konstruktion och tillverkning.
    Nicolescu, Cornel Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Manufacturing resource modelling for model driven operation planning2010Ingår i: Process Machine Interactions (PMI): Vancouver, Canada, June 10-11, 2010 / [ed] Prof. Y. Altintas, University of British Columbia, 2010Konferensbidrag (Refereegranskat)
    Abstract [en]

    Models of manufacturing resources as machine tools, fixtures and cutting tools contribute to efficient and simplified operation planning. With operation planning domain concept, defined in ontology and used during modelling of coherent ISO 10303-214 conforming data models of manufacturing resources, stable implementation solutions are ensured while capable of representing current manufacturing resources and resources developed in the future. Using similarities between different types of resources, a unified modelling approach may be applied independent of the type of object. Information classes as interfaces, kinematics, performance and behavior are identified and related to corresponding construct of the standardized product generic schema. With the common representation of shared information between applications domains as operation planning, maintenance and factory layout design, presented result contributes to set the basis for a digital factory used in virtual manufacturing to continuously improve the production system.

     

  • 56.
    Kayol, Bassam
    et al.
    KTH.
    Abu-Ghunmi, Diana
    Abu-Ghunmi, Lina
    Archenti, Andreas
    KTH, Skolan för industriell teknik och management (ITM).
    Nicolescu, Mihai
    KTH, Skolan för industriell teknik och management (ITM).
    Larkin, Charles
    Corbet, Shaen
    An economic index for measuring firm's circularity: The case of water industry2019Ingår i: Journal of Behavioral and Experimental Finance, ISSN 2214-6350, E-ISSN 2214-6369, Vol. 21, s. 123-129Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Transition toward circular-economy model is a must to sustain the planet sources. Under circular economy model wastewater is transformed from a ste into a resource. Therefore, a comprehensive circular economy dex; the Circonomics Index, is proposed to measure circularity of stewater industry. The component indicators of the index are linked rectly to the three Rs; reduce, reuse and recycle, of circular onomy. The novelty of the proposed Index is that it uses objectively nstructed weights that reflect the environmental benefits of the eatment process, and the index captures the reuse and recycling ficiency of an WWTP, which reflect the specific nature of wastewater. e findings show that treatment technology is a major factor in termining the production efficiency, reuse rate and recycling rformance of a WWTP. The results of using the Circonomics Index have ofound implication for policy makers to speed up the process of moving a circular economy.

  • 57.
    Krajnik, Peter
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Archenti, Andreas
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Pusavec, Franci
    University of Ljubljana, Faculty of Mechanical Engineering, Slovenia.
    Kopac, Janez
    University of Ljubljana, Faculty of Mechanical Engineering, Slovenia.
    Nicolescu, Cornel Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Investigation of Cryogenic Cooling Lubrication Effect on Machining System Operational Damping Ratio using Acoustic Signal2010Ingår i: CIRP International Conference on High Performance Cutting / [ed] Tojiro Aoyama, Yoshimi Takeuchi, 2010, s. 61-64Konferensbidrag (Refereegranskat)
  • 58.
    Krajnik, Peter
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Drazumeric, Radovan
    Badger, Jeffrey
    Kopac, Janez
    Nicolescu, Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Particularities of Grinding High Speed Steel Punching Tools2011Ingår i: Advances In Abrasive Technology XIV, Trans Tech Publications Inc., 2011, Vol. 325, s. 177-182Konferensbidrag (Refereegranskat)
    Abstract [en]

    A simulation model of a punch grinding process has been used to determine optimal parameters to reduce grinding cycle time and achieve a constant-temperature no-burn situation.Two basic outputs of the simulation model include arc length of contact and specific materialremoval rate that are both time-variant. A thermal model is included in the simulation to calculatemaximum grinding temperature rise. The simulation-based optimization can help to avoid thermal damage, which includes thermal softening, residual tensile stress, and rehardening burn. The grindability of high speed steel (HSS) is presented in terms of specific grinding energy versus undeformed chip thickness and maximum temperature rise versus specific material removal rate. Itis shown that for a given specific material removal rate lower temperatures are achieved when grinding fast and shallow. Higher temperatures, characteristic for slow and deep grinding, soften the material leading to a lower specific grinding energy, especially if grinding is timid. Lowest valuesof specific grinding energy can be achieved in fast and shallow grinding at aggressive grinding conditions.

  • 59.
    Krajnik, Peter
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Drazumeric, Radovan
    University of Ljubljana, Faculty of Mechanical Engineering, Ljubljana, Slovenia.
    Badger, Jeffrey
    The Grinding Doc Consulting, Austin, Texas, USA.
    Nicolescu, Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Kopac, Janez
    University of Ljubljana, Faculty of Mechanical Engineering, Ljubljana, Slovenia.
    A Novel and More Efficient Way to Grind Punching Tools2011Ingår i: Proceedings of The 4th International Swedish Production Symposium / [ed] Jan-Eric Ståhl, Lund: The Swedish Production Academy , 2011, s. 196-201Konferensbidrag (Refereegranskat)
    Abstract [en]

    A simulation model of punch grinding has been developed which calculates the instantaneous material-removal rate, arc length of contact and temperature based on the kinematic relationships between wheel and workiece and determines the optimum machine parameters to reduce cycle time and achieve a constant-temperature no-burn situation. Two basic outputs of the simulation model include arc length of contact and specific material-removal rate. A thermal model is included in the simulation to calculate maximum grinding zone temperature rise. A novel method is developed to constrain this temperature rise in the simulation. The thermal model inputs a constant value of specific grinding energy and the energy partition, which represents the fraction of the grinding energy conducted as heat to the workpiece. The simulation-based optimization can lead to a drastic reduction of grinding cycle time. Moreover, the limitation of maximum grinding zone temperature rise below the transitional temperature can help to avoid generation of workpiece thermal damage, which includes thermal softening, residual tensile stress, and rehardening burn. The grindability of high speed steel (HSS) is also discussed in terms of power consumption, specific grinding energy and undeformed chip thickness.

  • 60.
    Lundholm, Thomas
    et al.
    KTH, Tidigare Institutioner                               , Industriell produktion.
    Bergström, Erik
    KTH, Tidigare Institutioner                               , Industriell produktion.
    Enarson, Daniel
    Harder, Lars
    KTH, Tidigare Institutioner                               , Industriell produktion.
    Lindström, Bo
    KTH, Tidigare Institutioner                               , Industriell produktion.
    Nicolescu, Mihai
    KTH, Tidigare Institutioner                               , Industriell produktion.
    Nilsson, Bruno
    KTH, Tidigare Institutioner                               , Industriell produktion.
    NEW TECHNIQUES APPLIED TO ADAPTIVE CONTROLLED MACHINING1992Ingår i: Robotics and Computer-Integrated Manufacturing, ISSN 0736-5845, E-ISSN 1879-2537, Vol. 9, nr 4-5, s. 383-389Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The future capital intensive CIM and FMS systems will demand adaptive controlled (AC) machine tools. At the Department of Production Engineering of the Royal Institute of Technology in Stockholm (IMT/KTH) we are continuing the development of an advanced AC turning center. Our approach is to design and use sophisticated sensor systems to measure several features both on-line and off-line in order to obtain sufficient information on the cutting process and make adaptive feedback feasible. The AC system operates at three different levels: advanced process monitoring adaptive control constraint (ACC) adaptive control optimization (ACO). In this paper we give an overview of practical progress and improvements that have been achieved since our contribution to MSTF '87 in Cambridge.1 This includes: a new flexible sensor installation for optical tool wear measurements on-line tool wear estimation based upon a dynamic force sensor applied time series analysis for on-line chatter control real-time control of maching conditions with respect to cutting forces distributed real-time computer system solution.

  • 61.
    Nicolescu, Mihai
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Archenti, Andreas
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Dynamic parameter identification in nonlinear machining systems2013Ingår i: Journal of Machine Engineering, ISSN 1426-708X, Vol. 13, nr 3, s. 91-116Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The demand for enhanced performance of production systems in terms of quality, cost and reliability is ever increasing while, at the same time, there is a demand forshorter design cycles, longer operating life, minimisation of inspection and maintenance needs. Experimental testing and system identification in operational conditionsstill represent an important technique for monitoring, control andoptimization. The term identification refers in the present paper to the extraction of information from experimental data and is used to estimate operationaldynamic parameters for machining system. Such approach opens up the possibility of monitoring the dynamics of machining system during operational conditions, and to be used for control and/or predictive purposes. Machining system is considered non-linear and excited by random loads. Parametric and non-parametric techniques are developed for the identification of the non-linear machiningsystem and their application is demonstrated both by numerical simulations and in actual machining operations. Discrimination between forced and self-excitedvibration is also presented. The ability of the developed methods to estimate operational dynamic parameters ODPs is presented in practical machining operations.

  • 62.
    Nicolescu, Mihai
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Bayard, Ove
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Areskoug, Magnus
    Designing and Implementing a European Production Engineering Education2005Ingår i: 3rd CETUSS Workshop, Cross-disciplinarity in Engineering Education, Uppsala, Sweden, December 5th, 2005, 2005Konferensbidrag (Refereegranskat)
    Abstract [en]

    Modern production engineers must be able to perform a wide variety of tasks with steadily increasing complexity. In this context, it is especially important to endow production engineers with cross-disciplinary knowledge since this is vital to changing technology and international competition. Production engineering (PE) curricula must therefore keep pace with the changes demanded by future trends in advanced manufacturing. A homogenous production engineering curricula that specifies the most important areas in this field is a suitable platform to start from. The paper presents the some results from the EPRODE project being conducted by a number of European academic institutions and industrial organizations into manufacturing education issues. The aim of the project is to anticipate the needs for education of European and national manufacturing organizations of the future and to provide a unified framework for a common body of knowledge development that meet these needs.

  • 63.
    Nicolescu, Mihai
    et al.
    KTH, Skolan för industriell teknik och management (ITM).
    Frangoudis, C.
    KTH.
    Semere Tesfamariam, Daniel
    KTH, Skolan för industriell teknik och management (ITM).
    Archenti, Andreas
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Rashid, Amir
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    New Paradigm in Control of Machining System’s Dynamics2015Ingår i: Journal of Machine Engineering, Vol. 15, nr 3Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The increasing demands for precision and efficiency in machining call for effective control strategies based on the identification of static and dynamic characteristics under operational conditions. The capability of a machining system is significantly determined by its static and dynamic stiffness. The aim of this paper is to introduce novel concepts and methods regarding identification and control of a machining system’s dynamics. After discussing the limitations in current methods and technologies of machining systems’ identification and control, the paper introduces a new paradigm for controlling the machining system dynamics based on design of controllable structural Joint Interface Modules, JIMs, whose interface characteristics can be tuned using embedded actuators. Results from the laboratory and industrial implementation demonstrate the effectiveness of the control strategy with a high degree of repeatability.

  • 64.
    Nicolescu, Mihai
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Szafarczyk, Maciej
    Technical University of Warsaw.
    Bayard, Ove
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Chatti, Sami
    University of Dortmund.
    Requirements for Implementing the European Production Engineering Education2006Ingår i: 1st Jubilee Scientific Conference, Manufacturing Engineering in Time of Information Society, 1st – 2nd June, Gdansk, Poland, 2006 / [ed] Włodzimierz Przybylski, Politechnika Gdańska , 2006, s. 241-246Konferensbidrag (Refereegranskat)
    Abstract [en]

    Modern production engineers must be able to perform a wide variety of tasks with steadily increasing complexity. In this context, it is especially important to endow production engineers with cross-disciplinary knowledge since this is vital to changing technology and international competition. Production engineering (PE) curricula must therefore keep pace with changes demanded by future trends in advanced manufacturing. A homogenous production engineering curricula that specifies the most important topics in this field is a suitable platform to start from. The paper presents some results from the EPRODE project being conducted by a number of European academic institutions and industrial organizations for creating a framework for continuing education in production engineering. The aim of this paper is to anticipate the needs for education of a European production engineer and to provide a unified curriculum for a common body of knowledge that meet these needs. The modular structure of the curricula creates a systematic framework that is able to respond faster to changes in the state of the art.

  • 65. Pervaiz, S.
    et al.
    Deiab, I.
    Darras, B.
    Rashid, Amir
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Nicolescu, Cornel Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Performance evaluation of TiAlN- PVD coated inserts for machining Ti-6Al-4V under different cooling strategies2013Ingår i: Advanced Materials Research III, Trans Tech Publications Inc., 2013, Vol. 685, s. 68-75Konferensbidrag (Refereegranskat)
    Abstract [en]

    Titanium alloys are labeled as difficult to materials because of their low machinability rating. This paper presents an experimental study of machining Ti-6Al-4V under turning operation. All machining tests were conducted under dry, mist and flood cooling approaches by using a TiAlN coated carbide cutting inserts. All cutting experiments were conducted using high and low levels of cutting speeds and feed rates. The study compared surface finish of machined surface and flank wear at cutting edge under dry, mist and flood cooling approaches. Scanning electron microscopy was utilized to investigate the flank wear at cutting edge under various cooling approaches and cutting conditions. Investigation revealed that TiAlN coated carbides performed comparatively better at higher cutting speed.

  • 66. Pervaiz, S.
    et al.
    Deiab, I.
    Rashid, Amir
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Nicolescu, Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    An experimental analysis of energy consumption in milling strategies2012Ingår i: 2012 International Conference on Computer Systems and Industrial Informatics, ICCSII 2012, IEEE , 2012, s. 6454527-Konferensbidrag (Refereegranskat)
    Abstract [en]

    Pocket milling operation is one of the widely used milling operations. CAM packages offer different tool path strategies to execute a machining operation. In the presented work zigzag, constant overlap spiral, parallel spiral and oneway tool path strategies were compared in terms of power and energy consumption for pocket milling of Al 6061 aluminum alloy. All pocketing operations were conducted using 8 mm diameter High Speed Steel (HSS) end milling cutters. Energy utilization was analysed for all tool path strategies. This work aims to develop better understanding towards sustainability concept in core machining phase.

  • 67.
    Pervaiz, Salman
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Deiab, I
    Rashid, Amir
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Nicolescu, Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Experimental and numerical investigation of Ti6A14V alloy machinability using TiAIN coated tools2014Ingår i: Transactions of the North American Manufacturing Research Institution of SME, Society of Manufacturing Engineers , 2014, nr January, s. 104-113Konferensbidrag (Refereegranskat)
    Abstract [en]

    Titanium alloys exhibit extraordinary characteristics such as excellent strength-to-weight ratio, superior corrosive and erosive resistance and capability to operate at high operating temperatures. These alloys show poor machinability rating due their low thermal conductivity and high chemical reactivity. This study investigates the machinability of Ti6A14V using TiAIN coated tools by analyzing cutting forces and cutting temperatures. The simulated cutting force data was used to predict the total energy utilized by the process. Cutting tool temperatures during the machining operation were measured by an Infrared (IR) camera with cutting forces experiments. Finite element simulations can offer a cost effective solution when evaluating the machining performance of difficult to cut materials such as Titanium alloys. The study incorporated modified Johnson-Cook constitutive equation and friction model to develop the finite element simulations of the machining process. The finite element simulated results of forces and tool temperature presented good agreement with the experimental results. Copyright

  • 68.
    Pervaiz, Salman
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Deiab, Ibrahim
    Amir, Rashid
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Nicolescu, Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Prediction of energy consumption and environmental implications for turning operation using finite element analysis2015Ingår i: Proceedings of the Institution of mechanical engineers. Part B, journal of engineering manufacture, ISSN 0954-4054, E-ISSN 2041-2975, Vol. 229, nr 11Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This article is concerned with the experimental and numerical investigation of energy consumption involved in the turning of Ti6Al4V titanium alloys. Energy consumption of a machining process is considered as an important machining performance indicator. This article aims to propose an approach for the prediction of energy consumption and related environmental implications using finite element modeling simulations. Machining experiments were conducted using uncoated carbide tools under dry cutting environment. DEFORM-3D software package was utilized to simulate finite element–based machining simulations. Experimental validation was mainly conducted by focusing on the cutting forces and power consumption measurements. Simulated results of the cutting force and power consumption were found in a good agreement with the experimental findings. The amount of CO2 emission resulting from energy consumption during the machining phase is highly dependent on the geographical location. This study also incorporated the energy mix of United Arab Emirates for the environmental calculations. Finally, in the light of proposed methodology, possible future directions and recommendations have also been presented.

  • 69. Pervaiz, Salman
    et al.
    Deiab, Ibrahim
    Rashid, Amir
    Nicolescu, Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Influence of rake angle on the cutting energy when modeling the machining of Ti6Al4V2015Ingår i: 2015 10th International Symposium on Mechatronics and its Applications (ISMA), Institute of Electrical and Electronics Engineers (IEEE), 2015, artikel-id 7373461Konferensbidrag (Refereegranskat)
    Abstract [en]

    The finite element based machining simulations have been used widely in industry and academia to analyze the machining process. These virtual machining simulations have advantages over the real machining experiments due to the immense potential of saving time and expenses. The simulation techniques are even more popular when machining difficult to cut materials such as titanium alloy (Ti6Al4V). In order to make machining process sustainable in nature, energy consumption during the cutting process should be optimized accordingly. The present study aims to provide an insight towards the relation of cutting energy with respect to the different cutting tool geometries. The study used finite element based simulations to investigate the effect of rake angle on the cutting energy. Based on the cutting energy outcomes different suggestions were made to minimize the cutting energy.

  • 70.
    Pervaiz, Salman
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion. Amer Univ Sharjah, U Arab Emirates.
    Deiab, Ibrahim
    Rashid, Amir
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Nicolescu, Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Minimal quantity cooling lubrication in turning of Ti6Al4V: Influence on surface roughness, cutting force and tool wear2017Ingår i: Proceedings of the Institution of mechanical engineers. Part B, journal of engineering manufacture, ISSN 0954-4054, E-ISSN 2041-2975, Vol. 231, nr 9, s. 1542-1558Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Titanium alloys generally show low machinability ratings. They are referred as difficult-to-cut materials due to their inherent properties such as low thermal conductivity, high chemical reactivity and high strength at elevated temperatures. Cooling strategies play an important role to improve the machining performance of the cutting process. In order to facilitate the heat dissipation from the cutting zone, generous amount of coolant is used when machining highly reactive metals such as titanium alloys. Generally, cutting coolants are nominated as pollutants due to their non-biodegradable nature. This article presents experimental evaluation of a minimal quantity cooling lubrication system. The study investigates a combination of sub-zero-temperature air and vegetable oil-based mist as possible environmentally benign alternative to conventional cooling methods. The results are compared with the dry and flood cutting environments as well. Machinability was evaluated experimentally by considering the surface finish, cutting forces, tool life and their associated tool wear mechanisms. It was concluded from the results obtained from the surface roughness, cutting force and tool life investigation that minimal quantity cooling lubrication (internal) cooling strategy has encouraging potential to replace the conventional flood cooling method.

  • 71.
    Pervaiz, Salman
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Deiab, Ibrahim
    Rashid, Amir
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Nicolescu, Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Minimal Quantity Cooling Lubrication (MQCL) in Turning of Ti6Al4V: Influence on Surface roughness, Cutting force and Tool WearManuskript (preprint) (Övrigt vetenskapligt)
  • 72.
    Pervaiz, Salman
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion. American University of Sharjah, United Arab Emirates .
    Deiab, Ibrahim
    Wahba, Essam Moustafa
    Rashid, Amir
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Nicolescu, Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    A coupled FE and CFD approach to predict the cutting tool temperature profile in machining2014Ingår i: Procedia CIRP, ISSN 2212-8271, E-ISSN 2212-8271, Vol. 17, s. 750-754Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The paper presents an innovative methodology of coupling the conventional finite element machining simulations with computational fluid dynamic (CFD) model to analyse the temperature distribution at the cutting tool. The conventional finite element machining simulations were conducted using DEFORM 2D to predict the heat generation and tool tip temperature during the cutting action. Machining simulations were conducted using Ti6Al4V and uncoated carbide as a workpiece and tool material respectively. Modified version of Johnson-Cook constitutive model was incorporated in the conventional finite element based machining simulations to predict the behavior of flow stresses for Ti6Al4V titanium alloy. Computational fluid dynamics (CFD) simulations were performed using ANSYS (R) CFX. CFD model has incorporated air as a cooling media to simulate the dry cutting and temperature distribution at the tool surface was obtained. The coupled numerical modeling methodology showed encouraging potential of predicting precise temperature distribution on the cutting tool. The approach can be further evaluated to predict temperature distribution under flood cooling and minimum quantity lubrication (MQL).

  • 73.
    Pervaiz, Salman
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Deiab, Ibrahim
    University of Guelph, CANADA.
    Wahba, Essam
    Mechanical Engineering, American University of Sharjah.
    Rashid, Amir
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Nicolescu, Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    A novel numerical modeling approach to determine the temperature distribution in the cutting tool using conjugate heat transfer (CHT) analysis2015Ingår i: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 80, nr 5, s. 1039-1047Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study deals with the conjugate heat transfer problem of a single point cutting tool under turning operation dissipating heat in the tool material and streams of the surrounding air. In order to estimate the cutting temperature during the turning operation, the DEFORM-3D finite element package was utilized. A machining simulation material model for Ti6Al4V was utilized using a modified Johnson–Cook equation. The maximum cutting temperature value was obtained from the finite element model. The temperature was then used as a constant heat source on the tool tip, and the conjugate heat transfer (CHT) approach was used to develop a computational fluid dynamics (CFD) model. The CFD model utilized a 3D heat and fluid flow analysis using ANSYS ® CFX. A cutting insert with a constant heat source was exposed to the stream velocities of the dry air. The numerical equations governing the flow and thermal fields in the fluid domain and energy equation in the solid domain were solved in parallel by maintaining the continuity of temperature and heat flux at the solid–fluid interface. The presented conjugate heat transfer (CHT) approach provided a very useful understanding of the temperature profile development at the cutting tool that is still a complex challenge for the existing experimental and numerical techniques.

  • 74. Pervaiz, Salman
    et al.
    Deiab, Ibrahim
    Wahba, Essam
    Rashid, Amir
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Nicolescu, Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    A numerical and experimental study to investigate convective heat transfer and associated cutting temperature distribution in single point turning2018Ingår i: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 94, nr 1-4, s. 897-910Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    During the metal cutting operation, heat generation at the cutting interface and the resulting heat distribution among tool, chip, workpiece, and cutting environment has a significant impact on the overall cutting process. Tool life, rate of tool wear, and dimensional accuracy of the machined surface are linked with the heat transfer. In order to develop a precise numerical model for machining, convective heat transfer coefficient is required to simulate the effect of a coolant. Previous literature provides a large operating range of values for the convective heat transfer coefficients, with no clear indication about the selection criterion. In this study, a coupling procedure based on finite element (FE) analysis and computational fluid dynamics (CFD) has been suggested to obtain the optimum value of the convective heat transfer coefficient. In this novel methodology, first the cutting temperature was attained from the FE-based simulation using a logical arbitrary value of convective heat transfer coefficient. The FE-based temperature result was taken as a heat source point on the solid domain of the cutting insert and computational fluid dynamics modeling was executed to examine the convective heat transfer coefficient under similar condition of air interaction. The methodology provided encouraging results by reducing error from 22 to 15% between the values of experimental and simulated cutting temperatures. The methodology revealed encouraging potential to investigate convective heat transfer coefficients under different cutting environments. The incorporation of CFD modeling technique in the area of metal cutting will also benefit other peers working in the similar areas of interest.

  • 75.
    Pervaiz, Salman
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Rashid, Amir
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Deiab, I.
    Nicolescu, Cornel M.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    An experimental investigation on effect of minimum quantity cooling lubrication (MQCL) in machining titanium alloy (Ti6Al4V)2016Ingår i: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 87, nr 5-8, s. 1371-1386Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    During the machining operation, elevated temperatures are achieved at the cutting interface due to the presence of high plastic deformation and friction in between the tool and chip contacting area. Efficient heat dissipation from the cutting interface is required to achieve better machining performance. Elevated temperature in the cutting area results in lower tool life as it facilitates different types of wear mechanisms. Metal working fluids (MWFs) are employed to reduce heat and friction in the cutting zone, simultaneously to help in the flushing of waste particles. The MWFs are based on either water or petroleum oil and include several additives which make them non-biodegradable and toxic in nature. The minimum quantity lubrication (MQL) method offers a feasible substitute to the MWF-based conventional flood cooling method. In this study, a vegetable oil-based MQL system was mixed with sub-zero temperature air to design a new minimum quantity cooling lubrication (MQCL) system. The study investigates the machinability of Ti6Al4V using an MQCL system under various oil flow rates and compared its machining performance with both dry cutting and conventional flood cooling. For further evaluation, the study investigated surface roughness, flank wear, and associated wear mechanisms. It was found that in the MQCL system (60–70 ml/h), oil supply rates provided reliable machining performance at higher feed levels.

  • 76.
    Pervaiz, Salman
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Rashid, Amir
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Deiab, Ibrahim
    Nicolescu, Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Influence of Tool Materials on Machinability of Titanium- and Nickel-Based Alloys: A Review2014Ingår i: Materials and Manufacturing Processes, ISSN 1042-6914, E-ISSN 1532-2475, Vol. 29, nr 3, s. 219-252Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Titanium and nickel alloys are the most commonly used in the demanding industries like aerospace, energy, petrochemical, and biomedical. These highly engineered alloys offer unique combination of heat resistance, corrosion resistance, toughness, high operating temperature, and strength-to-weight ratio. These alloys are termed as "Difficult to cut materials" because of their low machinability rating. They are difficult to machine because of properties like low thermal conductivity, high strength at elevated temperatures, and high chemical reactivity. Machining of titanium- and nickel-based alloys causes problems of surface integrity and selection of cutting tool materials that is always a challenge for manufacturers. In this work, machinability studies for titanium and nickel alloys are reviewed with reference to cutting tool materials, associated wear mechanisms, failure modes, and novel tooling techniques. It also discusses major surface integrity defects like carbide cracking, white layer formation, work hardening layer formation, residual stresses, and microstructural alterations. Major aim of this work is to evaluate the challenges involved in improving machinability of the titanium- and nickel-based alloys, and determine the future research direction for productivity improvements in machining these alloys.

  • 77.
    Pervaiz, Salman
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Rashid, Amir
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Deiab, Ibrahim
    Nicolescu, Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Machinability of Ti6Al4V using minimum quantity cooling lubrication under various oil supply ratesManuskript (preprint) (Övrigt vetenskapligt)
  • 78.
    Pusavec, Franci
    et al.
    University of Ljubljana, Faculty of Mechanical Engineering, Ljubljana, Slovenia.
    Krajnik, Peter
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Nicolescu, Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Kopac, Janez
    University of Ljubljana, Faculty of Mechanical Engineering, Ljubljana, Slovenia.
    Residual Stresses, Plastic Work, and Microhardness in Cryogenic Machining of Inconel 7182011Ingår i: 4th International Swedish Production Symposium / [ed] Jan-Eric Stål, Lund: Swedish Production Academy , 2011, s. 283-288Konferensbidrag (Refereegranskat)
    Abstract [en]

    In machining of superalloys, a major quality performance characteristic refers to the integrity of the machined surface. In this consideration, the paper deals with a comparative evaluation of surface integrity in dry, minimum quantity lubrication (MQL), and cryogenic turning of Inconel 718. The comparison is concerned with residual stresses, plastic work, and microhardness developed under these different cooling lubrication conditions. The residual stresses generated on the workpiece surface were more tensile in the tangential (hoop) direction than in the axial direction. On the other hand, larger compressive stresses beneath the surface were observed in the axial direction. We have clearly observed that cryogenic machining resulted in higher compressive residual stresses when compared with dry or MQL machining. In addition, cryogenic machining yielded a thicker compressive zone of material beneath the machined surface. The correlation between residual stresses and plastic work suggested that the effects of mechanical loads, in comparison with thermal effects, were minor. It was further shown that the highest machined surface hardness was related to cryogenic cooling lubrication. In contrast to the microhardness variation, no drastic change in microstructure was observed. Moreover, no significant correlation between thermally induced phase transformation in a machined surface layer and microhardness was established.

  • 79.
    Rashid, Amir
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    A Asif, Farazee M
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Krajnik, Peter
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Nicolescu, Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Multiple Life Cycles Product Systems: Redefining the Manufacturing Paradigm for Resource Efficient Production and Consumption2012Konferensbidrag (Refereegranskat)
    Abstract [en]

    The products and the business models developed for conventional open-loop product systems are unable to cope with the requirements for resource efficiency. This paper redefines the conventional paradigm of closed-loop product systems and outlines the novel concept of multiple lifecycle products. The newly developed conceptual framework considers the conservation of energy, material and value added with waste prevention and environment protection as integrated components of the product design and development strategy. It also presents innovative ideas regarding designing products with multiple life cycles, business model for closed-loop supply chain, empowering customers, and multi-stakeholder approach required for the transition towards resource efficient production and consumption.

  • 80.
    Rashid, Amir
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Asif, Farazee M. A.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Krajnik, Peter
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Nicolescu, Cornel Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Resource Conservative Manufacturing: an essential change in business and technology paradigm for sustainable manufacturing2013Ingår i: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 57, s. 166-177Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    For sustainability of our future societies we need sustainable manufacturing strategies with resource and environment conservation as their integral part. In this perspective closed-loop supply chains are considered as the most feasible solution. However, their implementation within the paradigm of prevailing open-loop product systems seems extremely complicated and practically infeasible. This paper argues for a radical shift in thinking on the closed-loop systems and presents the novel concept of Resource Conservative Manufacturing (ResCoM). The ResCoM concept considers the conservation of energy, material and value added with waste prevention and environment protection as integrated components of the product design and development strategy. It also presents the innovative idea of products with multiple lifecycles where several lifecycles of predefined duration are determined already at the product design stage thus demanding for new design strategies and methodologies. To succeed with this concept ResCoM advocates for new approach to supply chain design and business models as well, where the customers are integral part of manufacturing enterprises and the product design is effectively connected with the supply chain design. This work concludes that the products, supply chains and the business models developed for open-loop product systems are unable to cope with the dynamics of closed-loop systems. The uncertainties associated with product returns are inherent to the conventional concept of lifecycle and closed-loop systems. The ResCoM concept has much better capability in dealing with these uncertainties while developing sustainable closed-loop systems. The presented work outlines and discusses the conceptual framework of ResCoM. A comprehensive work on the strategic and tactical issues in the implementation of the ResCoM concept will follow.

  • 81.
    Rashid, Amir
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Nicolescu, Cornel Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Active vibration control in palletised workholding system for milling2006Ingår i: International journal of machine tools & manufacture, ISSN 0890-6955, E-ISSN 1879-2170, Vol. 46, nr 12-13, s. 1626-1636Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper presents the development implementation and testing of an active controlled palletised workholding system for milling operations. The traditional approach to controlling vibration in a machining system is to develop control systems for cutting tools or machine spindles as in the case of milling machines. This work is a deviation from the traditional approach and targets a workholding system for the control of unwanted vibration. Palletised workholding systems, due to their compact design, offer an opportunity to design active control systems that are economical and easier to implement in the case of milling machines. The active control system developed here is based on an adaptive filtering algorithm, the filtered X-LMS, and employs piezo-actuators for dynamic control force. The system has been tested experimentally to demonstrate the reduction in dynamic force due to vibration. Extensive testing has been carried out to validate the performance of the system in terms of parameters of practical importance such as improvement in surface finish and increase in tool life.

  • 82.
    Rashid, Amir
    et al.
    System 3R International AB, Vällingby, Sweden.
    Nicolescu, Cornel Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Design and implementation of tuned viscoelastic dampers for vibration control in milling2008Ingår i: International journal of machine tools & manufacture, ISSN 0890-6955, E-ISSN 1879-2170, Vol. 48, nr 9, s. 1036-1053Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Passive means of vibration attenuation have been employed successfully and efficiently in machining systems such as turning and milling. Traditional approach to controlling vibration in a milling system is to develop control mechanisms for cutting tools or machine spindles. However, due to the nature of milling operations where the cutting tools rotate at high speed, the passive vibration control methods find very limited application with the traditional approach. In order to utilise the potential of the passive vibration control methodology in milling applications, the milling operation should be viewed as a system comprising an elastic structure and operation parameters. Dynamics of this closed-loop system should improve with improvement in dynamics of any of the system components, especially within the elastic structure that comprises the cutting tool, the machine tool, the workholding system and the workpiece. Although the level of improvement will vary depending on which component of the elastic chain is targeted for this purpose. This paper presents the development and testing of tuned viscoelastic dampers (TVDs) for vibration control through their application on a workpiece in milling operations. This work targets workpiece held on a palletised workholding system for the control of unwanted vibration and thus deviates from the traditional approach where cutting tool and/or machine spindles are targeted for vibration control strategies. Palletised workholding systems, due to their compact design, offer an opportunity to design passive damping mechanisms that are easier to implement in the case of a milling system. The TVD developed through this research is based on a commercially available viscoelastic damping polymer. Advantage of such materials is their high damping performance over a wide range of excitation frequencies. The TVD design process has used a unique combination of analytical modelling with experimental FRF data. Modal impact testing showed that the application of the TVD reduced the amplitude of vibration acceleration by 20dB for the target mode. Since the target mode corresponded to torsional vibration, the TVD was effective in two planar coordinates, i.e. X and Y. In addition, the TVD also significantly reduced the amplitude of a vibration mode far from the mode it was designed for. The system has been tested experimentally to demonstrate significant reduction in vibration amplitudes during a milling process. The milling tests with different combinations of cutting parameters show that multi-TVD approach is always valid regardless of the parameters being used. The only requirement for TVDs to function effectively is that the natural frequency of the system, for which the TVDs are designed, is excited during the milling process.

  • 83.
    Rashid, Amir
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Nicolescu, Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Experimental analysis of the influence of a high dampinginterface in a machining system designed for improvingmilling process performance2010Ingår i: Process machine interactions: conference proceedings, 2010Konferensbidrag (Refereegranskat)
    Abstract [en]

    Role of structural damping in the machining systems is well established andit is known that higher damping in machine tool structures extends the limits ofunconditional process stability regime in the stability lobes diagrams. Despite itssignificant contribution in process improvement the research on damping-basedimprovement in machining performance has been very limited in comparison toadaptive control of dynamic instability through optimum process parameters based onstability lobes’ characteristics of the machine tools. Conventional solutions forimproving damping in machining systems usually target one component at a time, e.g.cutting tools in case of boring bars, machine spindles in case of milling etc. Thisapproach has its limitations as the damping in single components can’t be increased tolevels for a significant contribution at the system level and very often withoutworsening their rigidity. An alternate to this conventional approach is to consider allcomponents of the elastic chain of the machining system- the machine, the cutting toolsand the workholding- for addition of damping, simultaneously. In this way a muchhigher amount of damping can be added into the system without deteriorating structuralrigidity of a single component. This research investigates the potential of high dampingin a milling system added through a workholding system, in this case. A High DampingInterface (HDI), based on a composite of metal-viscoelastic polymer is developed andintegrated in a palletized workholding system and analyzed experimentally. Theexperimental modal analysis and lab-machining tests show more than 50% reduction invibration amplitudes of natural frequency modes of the workpiece held on theworkholding system. The system is further tested in industrial machining environmentshowing up to 17x increase in metal removal rates and 100% improvement in surfacefinish in end milling operations. Ultimate objective of this research is to develop amachining system with its critical joint-interfaces replaced by HDIs with knowncharacteristics. The HDIs should be designed and distributed throughout the system in amanner that they play a dominant role in defining the dynamic behavior of themachining system.

  • 84.
    Wang, Yong
    et al.
    Wuhan Univ Technol, Wuhan, Hubei, Peoples R China.;KTH Royal Inst Technol, Stockholm, Sweden.;Hubei Business Serv Dev Res Ctr, Wuhan, Hubei, Peoples R China..
    Zhang, Pei-Lin
    Wuhan Univ Technol, Wuhan, Hubei, Peoples R China..
    Semere, Daniel
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Nicolescu, Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Zhang, Qing-Ying
    Wuhan Univ Technol, Wuhan, Hubei, Peoples R China..
    Research on Development Mechanism of "Family Farm" under E-commerce2018Ingår i: 2018 INTERNATIONAL CONFERENCE ON E-COMMERCE AND CONTEMPORARY ECONOMIC DEVELOPMENT (ECED 2018), DESTECH PUBLICATIONS, INC , 2018, s. 1-12Konferensbidrag (Refereegranskat)
    Abstract [en]

    Agricultural e-commerce will be the production and processing of agricultural products, organic combination of transportation storage and distribution sales process, the omni-directional into e-commerce system, through the computer information network, and with their own production base and advanced logistics distribution system as the backing, the convenience of using the Internet, to complete the purchase of agricultural products, sales, online payment and other related business process. Developing agricultural e-commerce is conducive to promoting agricultural development and farmers' income, and the "family farm", as a large-scale, intensive, the commercialization of agricultural management system, complied with the trend of the development of electronic commerce, so as to speed up the development of e-commerce, highlight the function mechanism of "family farm" in the agricultural e-commerce mechanism.

  • 85.
    Wanner, Bertil
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Archenti, Andreas
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Nicolescu, Cornel Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Hybrid machining: An industrial case-study comparing inconel718 reaming and drilling with abrasive waterjet technology2018Ingår i: Proceedings of 3rd International Conference on the Industry 4.0 Model for Advanced Manufacturing, Pleiades Publishing , 2018, nr 9783319895628, s. 109-114Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    Abrasive waterjet technology is one of the fastest growing metal cutting technologies. When used in conjunction with conventional metal cutting methods, abrasive waterjet cutting can be both cost saving and environmentally favorable. This paper shows that when processing hard to cut alloys, abrasive waterjet will be an excellent hybrid alternative. Reaming and drilling have traditionally been used to produce turbine blisks. Reaming is a highly expensive method since it uses very large amounts of cutting tools. Especially when cutting hard materials such as Nickel alloys, tools have to be replaced after only a few minutes of usage. By applying abrasive waterjet cutting to part of the process, the cost for tooling can be almost entirely eliminated. It will also increase the return profit for revert material and greatly reduce environmental emissions. This is because reaming and drilling produce chips while large amounts of cutting fluids are being used. Abrasive waterjet cutting will produce one large metal chunk per cut and uses no cutting fluids. This paper presents a method to combine abrasive waterjet cutting with reaming and drilling.

  • 86.
    Wanner, Bertil
    et al.
    KTH, Skolan för industriell teknik och management (ITM).
    Archenti, Andreas
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Nicolescu, Mihai
    KTH.
    HYBRID MACHINING: ABRASIVE WATERJET TECHNOLOGIES USED IN COMBINATION WITH CONVENTIONAL METAL CUTTING2017Ingår i: Journal of Machine Engineering, ISSN 1895-7595, Vol. 17, nr 3, s. 85-96Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Abrasive Waterjet technology is one of the fastest growing metal cutting technologies. Even so, very little published material is available on hybrid processing where abrasive waterjet cutting is one of two or more metal cutting methods. There is also limited published material on thin-walled components cut with abrasive waterjet technology. This paper makes a comparison of conventional metal cutting methods to the more unconventional abrasive waterjet technique. It will serve as a stepping stone in building knowledge aiding in hybrid machining development. It will show the possibilities and limitations during milling of thin-walled Aluminum components and then compare this to the capabilities of abrasive waterjet cutting the same components. Differences in material removal and revert control as well as in vibrations and force requirements will be reviewed. In addition, the environmental issues will be discussed and it will be determined which of the methods is more sustainable. The paper also includes a large section on process methodology.

  • 87.
    Werke, Mats
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Bagge, Mats
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Nicolescu, Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Lindberg, Bengt
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Process modelling using upstream analysis of manufacturing sequences2015Ingår i: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 81, nr 9-12, s. 1999-2016Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The manufacturing of components requires several manufacturing process steps that are performed in a sequence, during which the raw material is progressively converted into finished parts. The aim with simulation of manufacturing sequences is to replicate the aggregate effects of the process steps on key features of the finished product and manufacturing features. With the support of a successful simulation methodology, it will thereby be possible for process planners to evaluate virtually and select process steps to be included in the manufacturing sequence and to optimize process parameters. The motivation to implement sequential simulation in industry is therefore strong and will reduce time and cost in process planning. The modelling and simulation of complete manufacturing sequences is, however, a challenge which may lead to unrealistic and time-consuming modelling efforts and extensive computational requirements. This is due to the often complex material transformations through several consecutive process steps. In order to adapt sequential simulation into an industrial environment, simplifications are therefore necessary. This paper proposes a method for simplified metamodelling of manufacturing sequences, using upstream selection of process steps and definition of interconnected models. The method is presented as an algorithm and will improve the efficiency in the modelling of manufacturing sequences. The usability of the algorithm is demonstrated with two industrial cases: a bevel gear pinion and a steering arm.

  • 88.
    Werke, Mats
    et al.
    Swerea IVF.
    Hedlind, Mikael
    Scania CV AB.
    Nicolescu, Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Geometric Distortion Analysis Using CAD/CAM Based Manufacturing Simulation2014Ingår i: Proceedings of the 6th International Swedish Production Symposium, Chalmers university , 2014Konferensbidrag (Refereegranskat)
    Abstract [en]

    Machining of components may cause geometric distortions and thereby quality issues and increased costs. This paper presents an engineering approach of CAD/CAM based manufacturing simulation in order to be in control of geometric distortions after machining. The method utilises STEP AP209 for communication of CAD/CAM simulation data. The method improves the ability to optimise process parameters, geometry, and material, in order to fulfil the design requirements. The method supports concurrent design and process planning using 3D models in CAD/CAM and FEM.

  • 89.
    Werke, Mats
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi. Swerea IVF.
    Nicolescu, Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Semere, D.
    Variation analysis of manufacturing sequencesManuskript (preprint) (Övrigt vetenskapligt)
  • 90. Zhang, Q.
    et al.
    Nicolescu, Mihai
    KTH, Tidigare Institutioner, Industriell produktion.
    Jiang, X.
    Zhang, Y.
    Yue, W.
    Xiao, W.
    Sensors' network and its application in the intelligent storage security2004Ingår i: UNMANNED/UNATTENDED SENSORS AND SENSOR NETWORKS, 2004, s. 255-264Konferensbidrag (Refereegranskat)
    Abstract [en]

    Intelligent storage systems run on different advanced technologies, such as linear layout, business intelligence and data mining. Security, the basic desire of the storage system, has been focused on with the indraught of multimedia communication technology and sensors' network. Along with the developing of science and the social demands, multifarious alarming system has been designed and improved to be intelligentized, modularized and have network connections. It is of great moment to make the storage, and further more, the logistics system more and more efficient and perfect with modern science and technology. Diversified information on the spot should be caught by different kinds of sensors. Those signals are treated and communicated to the control center to give the further actions. For fire-proofing, broad-spectrum gas sensors, fume sensors, flame sensors and temperature sensors are used to catch the information in their own ways. Once the fire is taken somewhere, the sensors work by the fume, temperature, and flame as well as gas immediately. Meanwhile the intelligent control system starts. It passes the tidings to the center unit. At the same time, it sets those movable walls on to work quickly to obstruct the fire's spreading. While for guarding the warehouse against theft, cut-off sensors, body sensors, photoelectric sensors, microwave sensors and closed-circuit television as well as electronic clocks are available to monitor the warehouse reasonably. All of those sensors work in a net way. The intelligent control system is made with a digital circuit instead of traditional switch one. This system can work in a better way in many cases. Its reliability is high and the cost is low.

  • 91.
    Österlind, Tomas
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Archenti, Andreas
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Daghini, Lorenzo
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Nicolescu, Cornel Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Improvement of Gear Cutter Dynamics by Use of Acoustic Imaging and High Damping Interface2012Ingår i: 3rd CIRP Conference on Process Machine Interactions / [ed] Shamoto, E, 2012, s. 17-21Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper presents a study where acoustic imaging technology was employed for problem identification and high damping interfaces (HDI) were implemented in the machine tool structure to improve performance of process machine interaction, in bevel gear cutting, in terms of resistance to instability. Chatter marks at the gear root and tool fracturing represent a serious and widespread problem in the studied process. The acoustic image approach showed good agreement with modal analysis and also allowed to identify the chatter frequency. Once identified the problem, the paper also presents a novel approach for improving resistance to cutting instability by implementing HDI in the structure. The HDI consists of a viscoelastic composite material and is used to damp out the stick blade motion relative to the clamp block by transformation of vibratory energy, into heat. The primary contributions of this paper are the introduction of acoustic imaging for identification of chatter in gear cutting and employment of HDI for performance improvement for rotating tools.

  • 92.
    Österlind, Tomas
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Kari, Leif
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg, MWL Marcus Wallenberg Laboratoriet.
    Nicolescu, Cornel-Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Analysis of stationary displacement patterns in rotating machinery subject to local harmonic excitation2017Ingår i: Journal of Sound and Vibration, ISSN 0022-460X, E-ISSN 1095-8568, Vol. 389, s. 224-235Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Rotor vibration and stationary displacement patterns observed in rotating machineries subject to local harmonic excitation are analysed for improved understanding and dynamic characterization. The analysis stresses the importance of coordinate transformation between rotating and stationary frame of reference for accurate results and estimation of dynamic properties. A generic method which can be used for various rotor applications such as machine tool spindle and turbo machinery vibration is presented. The phenomenon shares similarities with stationary waves in rotating disks though focuses on vibration in shafts. The paper further proposes a graphical tool, the displacement map, which can be used for selection of stable rotational speed for rotating machinery. The results are validated through simulation of dynamic response of a milling cutter, which is a typical example of a variable speed rotor operating under different load conditions.

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