Kinetic and Strength Calculation of Age-Hardening Phases in Heat-Resistant Aluminum Alloys with Silver

In order to study the microstructures of heat-resistant aluminium alloys with silver in process of aging, kinetic and strength calculation were used to study the equilibrium and metastable phases of Al-4Cu-0.3Mg-0.4Ag alloy system. The main equilibrium phases were Liquid phase, α-Al matrix phase, Al2Cu phase, S phase (Al2CuMg) and AgMg phase, while metastable strengthening phases were Ω phase and θ’ phase. In addition, the kinetic parameters and aging strength of_Ω phase and θ’ phase that precipitated during aging were calculated. The calculated results shows that Ω phase has higher heat-resistant strengthening effect than θ’ phase.