Microstructure-based multiscale modeling of elevated temperature deformation in aluminum alloys

✍ Scribed by Paul E. Krajewski; Louis G. Hector Jr.; Ningning Du; Allan F. Bower

• Publisher: Elsevier Science
• Year: 2010
• Tongue: English
• Weight: 997 KB
• Volume: 58
• Category: Article
• ISSN: 1359-6454
• DOI: 10.1016/j.actamat.2009.10.023

✦ Synopsis

A multiscale model for predicting elevated temperature deformation in Al-Mg alloys is presented. Constitutive models are generated from a theoretical methodology and used to investigate the effects of grain size on formability. Flow data are computed with a polycrystalline, microstructure-based model which accounts for grain boundary sliding, stress-induced diffusion, and dislocation creep. Favorable agreement is found between the computed flow data and elevated temperature tensile measurements. A creep constitutive model is then fit to the computed flow data and used in finite-element simulations of two simple gas pressure forming processes, where favorable results are observed. These results are fully consistent with gas pressure forming experiments, and suggest a greater role for constitutive models, derived largely from theoretical methodologies, in the design of Al alloys with enhanced elevated temperature formability. The methodology detailed herein provides a framework for incorporation of results from atomistic-scale models of dislocation creep and diffusion.