Modified Plasticity Constitutive Model of Chinese 6061-T6 Aluminum Alloy

Abstract:

Aluminum alloy has been widely used in engineering structures. A plasticity constitutive model， which can accurately describe the elastoplastic behavior of aluminum alloy under complicated stress states， is of great significance to the analysis and design of aluminum alloy structures under complicated working conditions. The conventional von Mises yield criterion ignores the effect of stress state on metal plasticity， which is not suitable for aluminum alloy materials in complicated stress states. This paper conducts a series of tests to demonstrate that stress triaxiality and Lode angle can influence the plastic behavior of the 6061-T6 aluminum alloy. Based on the test results， a plasticity constitutive model suitable for 6061-T6 aluminum alloy in complicated stress states is proposed， and the full-range hardening law and the new yield criterion are calibrated， which can accurately simulate the elastoplastic behavior of Chinese structural 6061-T6 aluminum alloy in complicated stress states by comparing the experimental and numerical results.

Key words:aluminum alloy;plasticity constitutive model;stress triaxiality;Lode angle