Constitutive Model and Application of 2060 Aluminum-Lithium Alloy in Hot Stamping Process

Abstract:

2060 alloy, as the third generation aluminum-lithium (Al-Li) alloy, has lighter mass than traditional aluminum alloys and superior mechanical properties compared with previous generations of Al-Li alloy. The hot deformation behavior of 2060 Al-Li alloy sheets were investigated by hot tensile tests and model analysis. The fracture morphology was observed by scanning electron microscope. Then, the constitutive model coupled with the macroscopic mechanical behavior and the microstructure evolution was established. Finally, the established constitutive model was embedded in the finite element simulation software to analyze the deformation process of 2060 Al-Li alloy. The results show that the peak stress decreases with the increase in temperature and the decrease in strain rate. The deformation temperature has a significant impact on the anisotropy of the 2060 Al-Li alloy. It can be considered that the anisotropy can be eliminated at 400 °C or higher temperatures. It is found that the fracture process of 2060 Al-Li alloy conforms to typical ductile fracture laws. The presence of ridge improves the sheet deformation at elevated temperature. The constitutive model can predict the change of the true stress-true strain curves and the microstructure evolution accurately. The simulation results have good agreement with the experimental tests under hot stamping conditions.