深冷处理在ZL204铝合金中的应用

Application of cryogenic treatment in ZL204 aluminum alloy

研究了不同深冷处理工艺对ZL204铝合金力学性能以及残余应力消除效果的影响。结果表明,固溶后直接进行深冷处理,然后再进行人工时效时,合金的抗拉强度、屈服强度和伸长率与未深冷相比均得到一定的提升。另外,深冷处理的残余应力消除效果明显好于传统的去应力时效以及时效+循环热处理。ZL204铝合金最佳的残余应力消除工艺为540℃×9 h固溶,60℃水淬+-196℃×1 h深冷,在空气中放置1 h+175℃×3 h人工时效,空冷。

Influence of cryogenic treatment on mechanical properties and residual stress relief effect of ZL204 aluminum alloy was studied. The results show that the tensile strength,yield strength and elongation of the alloy increase when directly cryogenic treated after solution treatment and then artificial aged,and the effect of residual stress relief effect is better than the traditional relief aging and cycle heat treatment after aging. The best residual stress elimination process for ZL204 aluminum alloy is solution treated at 540 ℃ for 9 h with 60 ℃ water quenching,cryogenic treated at -196 ℃ for 1 h then stress relief aged for 1 h,and artificial aged at 175 ℃ for3 h with air cooling.