Research on Precipitation and Mechanical Properties of Al-Cu-0.4Mg-0.6Ag Alloy

The effect of Cu content on the precipitation and mechanical properties of Al-Cu-0.4Mg-0.6Ag alloy was investigated by tensile test,differential thermal analysis and microscopy observation.The results show that aging hardening and tensile strength increase with increasing Cu content,the tensile strength increase from 434MPa to 559 MPa at room temperature and from 141MPa to 228MPa at 300℃.The predominant hardening phases of Al-Cu-0.4Mg-0.6Ag are composed of flake Ω phase and a small amount of θ'phase at peak-aged stage at 185℃.The volume fraction of the Ω phase is increased with in creasing Cu content.