Phase-field simulation of weld solidification microstructure in an Al-Cu alloy
2008 (English)In: Modelling and Simulation in Materials Science and Engineering, ISSN 0965-0393, E-ISSN 1361-651X, Vol. 16, no 6Article in journal (Refereed) Published
Since the mechanical properties and the integrity of the weld metal depend on the solidification behaviour and the resulting microstructural characteristics, understanding weld pool solidification is of importance to engineers and scientists. Thermal and fluid flow conditions affect the weld pool geometry and solidification parameters. During solidification of the weld pool, a columnar grain structure develops in the weld metal. Prediction of the formation of the microstructure during welding may be an important and supporting factor for technology optimization. Nowadays, increasing computing power allows direct simulations of the dendritic and cell morphology of columnar grains in the molten zone for specific temperature conditions. In this study, the solidification microstructures of the weld pool at different locations along the fusion boundary are simulated during gas tungsten arc welding of Al-3wt% Cu alloy using the phase-field model for the directional solidification of dilute binary alloys. A macroscopic heat transfer and fluid flow model was developed to assess the solidification parameters, notably the temperature gradient and solidification growth rate. The effect of the welding speed is investigated. Computer simulations of the solidification conditions and the formation of a cellular morphology during the directional solidification in gas tungsten arc welding are described. Moreover, the simulation results are compared with existing theoretical models and experimental findings.
Place, publisher, year, edition, pages
2008. Vol. 16, no 6
to-equiaxed transition, fluid-flow, dendritic solidification, solute, redistribution, heat-transfer, growth, model, prediction, parameters, diagram
IdentifiersURN: urn:nbn:se:kth:diva-17755DOI: 10.1088/0965-0393/16/6/065005ISI: 000258385800005ScopusID: 2-s2.0-51349090971OAI: oai:DiVA.org:kth-17755DiVA: diva2:335800
QC 201005252010-08-052010-08-05Bibliographically approved