Al-Cu-Mg-Ag-Zr合金高温持久后的组织与性能

研究Al-Cu-Mg-Ag-Zr合金在165℃时效组织与性能的变化,并采用欠时效态(165℃×2h)的试样进行200℃及外加应力为200MPa的高温持久试验。结果表明,欠时效态的试样在高温持久下,随时间延长,其剩余强度先上升后下降,强度峰值出现在持久20h。延伸率变化与强度变化基本相似。持久100h后,合金力学性能相对欠时效态无明显下降,显示出优良的热稳定性。

Microstructures and properties of Al-Cu-Mg-Ag-Zr alloy after high temperature lasting

The microstructure and performance of Al-Cu-Mg-Ag alloy aging at 165 ℃ have been investigated, and the high temperature lasting test is done at 200 ℃ and 200 MPa for underageing (165 ℃×2 h) samples. The results indicate that with the lasting time prolonging, the residual stress of underageing samples appears to increase first and then decrease ,and the peaking stress is obtained when lasting for 20 h. The variation of ductility of the underageing samples has the same tendency with the variation of residual stress. Compared with underageing condition, the mechanical properties have no obvious variation after lasting for 100 h, which represents a superior heat-resistance ability .