The construction and use of plasticity models to predict elevated temperature forming of magnesium ZEK100 alloy sheet material

Abstract

Mechanical Engineering

Magnesium (Mg) alloys provide material properties that make them attractive for structural components. In particular Mg alloys can be used to produce components with lighter weight than most alloy sheets currently used. However, the insufficient ductility of Mg alloy sheet materials at room temperature can require these to be formed at elevated temperatures to achieve suitable formability. In this research, wrought Mg alloy ZEK100 is studied at 300 °C and lower temperatures. Behavior at these lower temperatures is compared to behavior of 450 °C and 350 °C. A goal of this study is to determine the possibilities for future forming technologies at these lower temperatures. The deformation mechanisms at these temperatures are examined, including their relation to plastic anisotropy. Knowledge of the active deformation mechanisms is used to formulate descriptive models of plastic deformation. Material constitutive models are constructed and used in finite element method (FEM) simulations of gas pressure bulge tests. Finally, results of FEM simulations are compared with experimental results, and the accuracies of the material constitutive models are validated.