ICME 指导高强 Al-Cu-Li 合金设计

To design high-strength Al-Cu-Li alloys more efficiently, the relations between temperature and phases in Al-Cu-Li alloy were calculated based on thermodynamics. Based on the finite element method(FEM), the temperature field evolution and cooling rate of 2050 alloy in semi-continuous casting were simulated. The stress-strain relationship of T34-2050 alloy with rolling texture was also predicted by crystal plasticity FEM, and the pre-stretching level of the alloy before stress aging was determined to be 7%-9%. The above calculation results were integrated into the actual manufacturing process of stress-aged 2050 alloy. The mechanical properties and precipitation phase evolution of 2050 alloy after stress aging were characterized by room temperature stretching and transmission electron microscopy. The results show that a good strength-plastic matching of the 2050 alloy with 9% pre-strain can be achieved under the stress aging conditions of 200 ℃ ×7 h, with a yield strength of over 600 MPa and an elongation of more than 8%.