kth.sePublications
Change search
Link to record
Permanent link

Direct link
Publications (10 of 87) Show all publications
Dastanpour Hosseinabadi, E., Huang, S., Ström, V., Varga, L. K., Vitos, L. & Schönecker, S. (2024). An assessment of the Al50Cr21-xMn17+xCo12 (x=0, 4, 8) high-entropy alloys for magnetocaloric refrigeration application. Journal of Alloys and Compounds, 984, 173977, Article ID 173977.
Open this publication in new window or tab >>An assessment of the Al50Cr21-xMn17+xCo12 (x=0, 4, 8) high-entropy alloys for magnetocaloric refrigeration application
Show others...
2024 (English)In: Journal of Alloys and Compounds, ISSN 0925-8388, E-ISSN 1873-4669, Vol. 984, p. 173977-, article id 173977Article in journal (Refereed) Published
Abstract [en]

This study investigates the magnetocaloric potential of the Al50Cr21-xMn17+xCo12 (x=0, 4, 8 at%) high-entropy alloy (HEA) series using integrated experimental and theoretical approaches. Structural analysis by X-ray diffraction and scanning electron microscopy indicate a dual phase containing B2 and body-centered cubic (BCC) structures. Magnetic characterization shows an approximately linear decrease in saturation magnetization and Curie temperature with increasing Cr content. Curie temperatures calculated by Monte Carlo simulations suggest that the measured magnetic properties originate from the B2 phase rather than the BCC phase. The enhanced magnetocaloric effect with decreasing Cr content highlights the attractiveness of HEAs in magnetocaloric applications.

Place, publisher, year, edition, pages
Elsevier BV, 2024
Keywords
B2 structure, High entropy alloys, Magnetic properties, Magnetocaloric effect, Monte Carlo
National Category
Condensed Matter Physics
Identifiers
urn:nbn:se:kth:diva-344344 (URN)10.1016/j.jallcom.2024.173977 (DOI)001195417200001 ()2-s2.0-85186459945 (Scopus ID)
Note

QC 20240314

Available from: 2024-03-13 Created: 2024-03-13 Last updated: 2024-04-15Bibliographically approved
Masood, A., Belova, L. & Ström, V. (2024). Magnetic anisotropy in heterogeneous amorphous thin films: insights from thickness- and temperature-driven spin-reorientation. Journal of Physics D: Applied Physics, 57(31), Article ID 315002.
Open this publication in new window or tab >>Magnetic anisotropy in heterogeneous amorphous thin films: insights from thickness- and temperature-driven spin-reorientation
2024 (English)In: Journal of Physics D: Applied Physics, ISSN 0022-3727, E-ISSN 1361-6463, Vol. 57, no 31, article id 315002Article in journal (Refereed) Published
Abstract [en]

Magnetization orientation in thin films is intricately influenced by multiple anisotropy components, with the dominant anisotropy serving as a key determinant. This complexity becomes particularly intriguing when considering thin films composed of subnanometer-scale heterogeneous amorphous structures. Our investigation builds upon this foundation, specifically focusing on the Fe-Ni-B-Nb alloy system, known for its moderate glass-forming ability and susceptibility to nanocrystallization. In this study, we present thickness- and temperature-driven spin-reorientation (SRT) transition, attributed to competing magnetic anisotropy energies in thin films featuring a heterogeneous amorphous structure. Thermogravimetric investigations unveiled a unique heterogeneous amorphous structure, a revelation unattainable through conventional structural analysis methods. The observed spontaneous perpendicular magnetization in amorphous films, as evidenced by transcritical hysteresis loops and magnetic stripe domains, is ascribed to the pronounced residual stress arising from the substantial magnetostriction of the alloy system. The temperature-driven SRT is correlated to the order-disorder magnetic transition of the heterogeneous amorphous phase, characterized by a Curie temperature of ∼225 K. This transformative magnetic state of the heterogeneous amorphous matrix limits the exchange interaction among the densely distributed α-Fe nuclei regions, ultimately governing the dynamic magnetic responses with varying temperature. This work provides valuable insights into the dynamic magnetic orientation of thin films, especially those with heterogeneous amorphous structures, contributing to the broader understanding of the underlying mechanisms of magnetization reversals.

Place, publisher, year, edition, pages
IOP Publishing, 2024
Keywords
Fe-based amorphous thin films, perpendicular magnetic anisotropy, perpendicular magnetization, pulse laser deposition, spin-reorientation transition
National Category
Condensed Matter Physics
Identifiers
urn:nbn:se:kth:diva-346797 (URN)10.1088/1361-6463/ad4659 (DOI)001222067400001 ()2-s2.0-85193079657 (Scopus ID)
Note

QC 20240527

Available from: 2024-05-24 Created: 2024-05-24 Last updated: 2024-08-14Bibliographically approved
Masood, A., Belova, L. & Ström, V. (2024). Magnetic Hardening: Unveiling Magnetization Dynamics in Soft Magnetic Fe–Ni–B–Nb Thin Films at Cryogenic Temperatures. Nanomaterials, 14(14), Article ID 1218.
Open this publication in new window or tab >>Magnetic Hardening: Unveiling Magnetization Dynamics in Soft Magnetic Fe–Ni–B–Nb Thin Films at Cryogenic Temperatures
2024 (English)In: Nanomaterials, E-ISSN 2079-4991, Vol. 14, no 14, article id 1218Article in journal (Refereed) Published
Abstract [en]

Recent advancements in amorphous materials have opened new avenues for exploring unusual magnetic phenomena at the sub-nanometer scale. We investigate the phenomenon of low-temperature “magnetic hardening” in heterogeneous amorphous Fe–Ni–B–Nb thin films, revealing a complex interplay between microstructure and magnetism. Magnetization hysteresis measurements at cryogenic temperatures show a significant increase in coercivity (HC) below 25 K, challenging the conventional Random Anisotropy Model (RAM) in predicting magnetic responses at cryogenic temperatures. Heterogeneous films demonstrate a distinct behavior in field-cooled and zero-field-cooled temperature-dependent magnetizations at low temperatures, characterized by strong irreversibility. This suggests spin-glass-like features at low temperatures, which are attributed to exchange frustration in disordered interfacial regions. These regions hinder direct exchange coupling between magnetic entities, leading to magnetic hardening. This study enhances the understanding of how microstructural intricacies impact magnetic dynamics in heterogeneous amorphous thin films at cryogenic temperatures.

Place, publisher, year, edition, pages
MDPI AG, 2024
Keywords
heterogeneous amorphous films, low-temperature magnetization, magnetic hardening, magnetic transitions, spin-glass
National Category
Condensed Matter Physics
Identifiers
urn:nbn:se:kth:diva-351699 (URN)10.3390/nano14141218 (DOI)001277629300001 ()2-s2.0-85199859035 (Scopus ID)
Note

QC 20240814

Available from: 2024-08-13 Created: 2024-08-13 Last updated: 2024-08-14Bibliographically approved
Hoogendoorn, B. W., Karlsson, O., Xiao, X., Pandey, A., Mattsson, S.-E., Ström, V., . . . Olsson, R. (2023). Cellulose nanofibers (CNFs) in the recycling of nickel and cadmium battery metals using electrodeposition. Nanoscale Advances, 5(19), 5263-5275
Open this publication in new window or tab >>Cellulose nanofibers (CNFs) in the recycling of nickel and cadmium battery metals using electrodeposition
Show others...
2023 (English)In: Nanoscale Advances, E-ISSN 2516-0230, Vol. 5, no 19, p. 5263-5275Article in journal (Refereed) Published
Abstract [en]

Cellulose nanofibers (CNFs) were employed in the aqueous electrodeposition of nickel and cadmium for battery metal recycling. The electrowinning of mixed Ni-Cd metal ion recycling solutions demonstrated that cadmium with a purity of over 99% could be selectively extracted while leaving the nickel in the solution. Two types of CNFs were evaluated: negatively charged CNFs (a-CNF) obtained through acid hydrolysis (−75 μeq. g−1) and positively charged CNFs (q-CNF) functionalized with quaternary ammonium groups (+85 μeq. g−1). The inclusion of CNFs in the Ni-Cd electrolytes induced growth of cm-sized dendrites in conditions where dendrites were otherwise not observed, or increased the degree of dendritic growth when it was already present to a lesser extent. The augmented dendritic growth correlated with an increase in deposition yields of up to 30%. Additionally, it facilitated the formation of easily detachable dendritic structures, enabling more efficient processing on a large scale and enhancing the recovery of the toxic cadmium metal. Regardless of the charged nature of the CNFs, both negatively and positively charged CNFs led to a significant formation of protruding cadmium dendrites. When deposited separately, dendritic growth and increased deposition yields remained consistent for the cadmium metal. However, dendrites were not observed during the deposition of nickel; instead, uniformly deposited layers were formed, albeit at lower yields (20%), when positively charged CNFs were present. This paper explores the potential of utilizing cellulose and its derivatives as the world's largest biomass resource to enhance battery metal recycling processes.

Place, publisher, year, edition, pages
Royal Society of Chemistry (RSC), 2023
National Category
Materials Chemistry
Identifiers
urn:nbn:se:kth:diva-349876 (URN)10.1039/d3na00401e (DOI)001031237900001 ()2-s2.0-85166331036 (Scopus ID)
Note

QC 20240704

Available from: 2024-07-04 Created: 2024-07-04 Last updated: 2024-07-04Bibliographically approved
Huang, S., Dastanpour Hosseinabadi, E., Schönecker, S., Ström, V., Chai, G., Kiss, L. F., . . . Vitos, L. (2023). Combinatorial design of partial ordered Al-Cr-Mn-Co medium-entropy alloys for room temperature magnetic refrigeration applications. Applied Physics Letters, 123(4), Article ID 044103.
Open this publication in new window or tab >>Combinatorial design of partial ordered Al-Cr-Mn-Co medium-entropy alloys for room temperature magnetic refrigeration applications
Show others...
2023 (English)In: Applied Physics Letters, ISSN 0003-6951, E-ISSN 1077-3118, Vol. 123, no 4, article id 044103Article in journal (Refereed) Published
Abstract [en]

Multi-component alloys have received increasing interest for functional applications in recent years. Here, we explore the magnetocaloric response for Al-Cr-Mn-Co medium-entropy alloys by integrated theoretical and experimental methods. Under the guidance of thermodynamic and ab initio calculations, a dual-phase system with large magnetic moment, i.e., Al50Cr19Mn19Co12, is synthesized, and the structural and magnetocaloric properties are confirmed via characterization. The obtained results indicate that the selected alloy exhibits a co-continuous mixture of a disordered body-centered cubic and an ordered B2 phase. The ab initio and Monte Carlo calculations indicate that the presence of the ordered B2 phase is responsible for the substantial magnetocaloric effect. The magnetization measurements demonstrated that this alloy undergoes a second-order magnetic transition with the Curie temperature of ∼300 K. The magnetocaloric properties are examined using magnetic entropy change, refrigeration capacity, and adiabatic temperature change. The property-directed strategy explored here is intended to contribute to the study of potential multi-component alloys in magnetocaloric applications.

Place, publisher, year, edition, pages
AIP Publishing, 2023
National Category
Metallurgy and Metallic Materials
Identifiers
urn:nbn:se:kth:diva-334743 (URN)10.1063/5.0160477 (DOI)001036269500006 ()2-s2.0-85166122676 (Scopus ID)
Note

QC 20230824

Available from: 2023-08-24 Created: 2023-08-24 Last updated: 2023-08-24Bibliographically approved
Dastanpour Hosseinabadi, E., Huang, S., Dong, Z., Schönecker, S., Ström, V., Eriksson, O., . . . Vitos, L. (2023). Investigation of the metastable spinodally decomposed magnetic CrFe-rich phase in Al doped CrFeCoNi alloy. Journal of Alloys and Compounds, 939, 168794, Article ID 168794.
Open this publication in new window or tab >>Investigation of the metastable spinodally decomposed magnetic CrFe-rich phase in Al doped CrFeCoNi alloy
Show others...
2023 (English)In: Journal of Alloys and Compounds, ISSN 0925-8388, E-ISSN 1873-4669, Vol. 939, p. 168794-, article id 168794Article in journal (Refereed) Published
Abstract [en]

We have conducted an in-depth study of the magnetic phase due to a spinodal decomposition of the BCC phase of a CrFe-rich composition. This magnetic phase is present after casting (arc melting) or water quenching after annealing at 1250 degrees C for 24 h but is entirely absent after annealing in the interval 900-1100 degrees C for 24 h. Its formation is favored in the temperature interval ca 450-550 degrees C and loses magnetization above 640 degrees C. This ferromagnetic-paramagnetic transition is due to a structural transformation from ferromagnetic BCC into paramagnetic sigma and FCC phases. The conclusion from measurements at different heating rates is that both the transformation leading to the increase of the magnetization due to the spinodal decomposition of the parent phase and the vanishing magnetization at 640 degrees C are diffusion controlled.

Place, publisher, year, edition, pages
Elsevier BV, 2023
Keywords
High entropy alloy, AlCrFeCoNi, Spinodal decomposition, Structural transformation, Magnetization
National Category
Metallurgy and Metallic Materials
Identifiers
urn:nbn:se:kth:diva-329905 (URN)10.1016/j.jallcom.2023.168794 (DOI)000996492500001 ()2-s2.0-85146081676 (Scopus ID)
Note

QC 20230626

Available from: 2023-06-26 Created: 2023-06-26 Last updated: 2023-06-26Bibliographically approved
Masood, A., Belova, L. & Ström, V. (2023). Magnetization dynamics and spin-glass-like origins of exchange-bias in Fe-B-Nb thin films. Journal of Applied Physics, 134(24), Article ID 243903.
Open this publication in new window or tab >>Magnetization dynamics and spin-glass-like origins of exchange-bias in Fe-B-Nb thin films
2023 (English)In: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 134, no 24, article id 243903Article in journal (Refereed) Published
Abstract [en]

The phenomenon of exchange bias has been extensively studied within crystalline materials, encompassing a broad spectrum from nanoparticles to thin-film systems. Nonetheless, exchange bias in amorphous alloys has remained a relatively unexplored domain, primarily owing to their inherently uniform disordered atomic structure and lacking grain boundaries. In this study, we present a unique instance of exchange bias observed in Fe-B-Nb amorphous thin films, offering insights into its origins intertwined with the system's spin-glass-like behavior at lower temperatures. The quantification of exchange bias was accomplished through a meticulous analysis of magnetic reversal behaviors in the liquid-helium temperature range, employing a zero-field cooling approach from various initial remanent magnetization states (±MR). At reduced temperatures, the appearance of asymmetric hysteresis, a hallmark of negative exchange bias, undergoes a transformation into symmetric hysteresis loops at elevated temperatures, underscoring the intimate connection between exchange-bias and dynamic magnetic states. Further investigations into the magnetic thermal evolution under varying probe fields reveal the system's transition into a spin-glass-like state at low temperatures. We attribute the origin of this unconventional exchange bias to the intricate exchange interactions within the spin-glass-like regions that manifest at the interfaces among highly disordered Fe-nuclei. The formation of Fe-nuclei agglomerates at the sub-nanometer scale is attributed to the alloy's limited glass-forming ability and the nature of the thin-film fabrication process. We propose that this distinctive form of exchange bias represents a novel characteristic of amorphous thin films.

Place, publisher, year, edition, pages
AIP Publishing, 2023
National Category
Condensed Matter Physics
Identifiers
urn:nbn:se:kth:diva-342184 (URN)10.1063/5.0179602 (DOI)001135686300007 ()2-s2.0-85181102095 (Scopus ID)
Note

QC 20240115

Available from: 2024-01-15 Created: 2024-01-15 Last updated: 2024-08-14Bibliographically approved
Dastanpour Hosseinabadi, E., Huang, S., Schönecker, S., Mao, H., Ström, V., Eriksson, O., . . . Vitos, L. (2023). On the structural and magnetic properties of Al-rich high entropy alloys: a joint experimental-theoretical study. Journal of Physics D: Applied Physics, 56(1), Article ID 015003.
Open this publication in new window or tab >>On the structural and magnetic properties of Al-rich high entropy alloys: a joint experimental-theoretical study
Show others...
2023 (English)In: Journal of Physics D: Applied Physics, ISSN 0022-3727, E-ISSN 1361-6463, Vol. 56, no 1, article id 015003Article in journal (Refereed) Published
Abstract [en]

The present work investigates how the vanadium (V) content in a series of Al50V (x) (Cr0.33Mn0.33Co0.33)((50-x)) (x = 12.5, 6.5, 3.5, and 0.5 at.%) high-entropy alloys affects the local magnetic moment and magnetic transition temperature as a step towards developing high-entropy functional materials for magnetic refrigeration. This has been achieved by carrying out experimental investigations on induction melted alloys and comparison to ab initio and thermodynamic calculations. Structural characterization by x-ray diffraction and scanning electron microscopy indicates a dual-phase microstructure containing a disordered body-centered cubic (BCC) phase and a B2 phase with long-range order, which significantly differ in the Co and V contents. Ab initio calculations demonstrate a weaker magnetization and lower magnetic transition temperature (T

Place, publisher, year, edition, pages
IOP Publishing, 2023
Keywords
magnetic materials, high entropy alloys, ab initio, B2 structure, magnetic transition temperature, V content
National Category
Condensed Matter Physics Metallurgy and Metallic Materials
Identifiers
urn:nbn:se:kth:diva-323091 (URN)10.1088/1361-6463/aca1ce (DOI)000897771000001 ()2-s2.0-85144560264 (Scopus ID)
Note

QC 20230118

Available from: 2023-01-18 Created: 2023-01-18 Last updated: 2023-01-18Bibliographically approved
Hoogendoorn, B. W., Birdsong, B. K., Capezza, A. J., Ström, V., Li, Y., Xiao, X. & Olsson, R. (2022). Ultra-low Concentration of Cellulose Nanofibers (CNFs) for Enhanced Nucleation and Yield of ZnO Nanoparticles. Langmuir, 38(41), 12480-12490
Open this publication in new window or tab >>Ultra-low Concentration of Cellulose Nanofibers (CNFs) for Enhanced Nucleation and Yield of ZnO Nanoparticles
Show others...
2022 (English)In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 38, no 41, p. 12480-12490Article in journal (Refereed) Published
Abstract [en]

Cellulose nanofibers (CNFs) were used in aqueous synthesis protocols for zinc oxide (ZnO) to affect the formation of the ZnO particles. Different concentrations of CNFs were evaluated in two different synthesis protocols producing distinctly different ZnO morphologies (flowers and sea urchins) as either dominantly oxygen-or zinc-terminated particles. The CNF effects on the ZnO formation were investigated by implementing a heat-treatment method at 400 degrees C that fully removed the cellulose material without affecting the ZnO particles made in the presence of CNFs. The inorganic phase formations were monitored by extracting samples during the enforced precipitations to observe changes in the ZnO morphologies. A decrease in the size of the ZnO particles could be observed for all synthesis protocols, already occurring at small additions of CNFs. At as low as 0.1 g/L CNFs, the particle size decreased by 50% for the flower-shaped particles and 45% for the sea-urchin-shaped particles. The formation of smaller particles was accompanied by increased yield by 13 and 15% due to the CNFs' ability to enhance the nucleation, resulting in greater mass of ZnO divided among a larger number of particles. The enhanced nucleation could also be verified as useful for preventing secondary morphologies from forming, which grew on the firstly precipitated particles. The suppression of secondary growths' was due to the more rapid inorganic phase formation during the early phases of the reactions and the faster consumption of dissolved salts, leaving smaller amounts of metal salts present at later stages of the reactions. The findings show that using cellulose to guide inorganic nanoparticle growth can be predicted as an emerging field in the preparation of functional inorganic micro/nanoparticles. The observations are highly relevant in any industrial setting for the large-scale and resource-efficient production of ZnO.

Place, publisher, year, edition, pages
American Chemical Society (ACS), 2022
National Category
Inorganic Chemistry
Identifiers
urn:nbn:se:kth:diva-321261 (URN)10.1021/acs.langmuir.2c01713 (DOI)000874223000001 ()36200128 (PubMedID)2-s2.0-85139961062 (Scopus ID)
Note

QC 20221111

Available from: 2022-11-11 Created: 2022-11-11 Last updated: 2023-05-17Bibliographically approved
Dastanpour, E., Enayati, M. H., Masood, A. & Ström, V. (2021). Crystallization behavior, soft magnetism and nanoindentation of Fe–Si–B–P–Cu alloy on Ni substitution. Journal of Alloys and Compounds, 851, Article ID 156727.
Open this publication in new window or tab >>Crystallization behavior, soft magnetism and nanoindentation of Fe–Si–B–P–Cu alloy on Ni substitution
2021 (English)In: Journal of Alloys and Compounds, ISSN 0925-8388, E-ISSN 1873-4669, Vol. 851, article id 156727Article in journal (Refereed) Published
Abstract [en]

The present work investigates how the substitution of Ni for Fe in the amorphous precursor of the high flux density Fe–Si–B–P–Cu (Nanomet®) alloy avoids the creation of detrimental pre-existing nuclei in the amorphous precursor as a step forward for improved amorphization capability, retains homogenous nanocrystalline structure with excellent soft magnetic properties, and affects the mechanical properties in terms of reduced hardness and Young's modulus. This has been achieved by adding Ni of various concentrations (0–8 atomic %). The investigation includes structural characterization, calorimetry, optimization of annealing temperature, extensive magnetic characterization and nanoindentation to assess the mechanical properties. The excellent soft magnetic properties demonstrate a strategy to deploy the nanocrystalline ribbons where freedom of device design is a limiting factor for electrodynamic energy conversion applications.

Place, publisher, year, edition, pages
Elsevier BV, 2021
Keywords
Nanocrystalline, Nanoindentation, Nanomet, Ni-substitution, Soft magnetic properties, Amorphous silicon, Copper alloys, Crystallization, Density (specific gravity), Elastic moduli, Energy conversion, Magnetic properties, Magnetism, Nanocrystals, Amorphous precursors, Annealing temperatures, Crystallization behavior, Magnetic characterization, Nano-crystalline structures, Nanocrystalline ribbon, Structural characterization, Nanocrystalline alloys
National Category
Metallurgy and Metallic Materials Other Materials Engineering
Identifiers
urn:nbn:se:kth:diva-285275 (URN)10.1016/j.jallcom.2020.156727 (DOI)000579868900025 ()2-s2.0-85089884729 (Scopus ID)
Note

Correction in:Journal Of Alloys And Compounds

Volume:878; Article Number 160527; DOI10.1016/j.jallcom.2021.160527;

Accession Number WOS:000660479000005

Available from: 2020-12-03 Created: 2020-12-03 Last updated: 2022-09-26Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0003-2170-0076

Search in DiVA

Show all publications