摘要
制备了Zr含量为(质量分数)0.2%和0.5%的ZA27合金铸锭,并对合金进行了370℃×12h固溶处理及100℃人工时效处理。结果表明,0.2%的Zr可以使ZA27合金发达的树枝晶变为细小的花瓣状枝晶,起到显著的变质作用,而Zr含量为0.5%的合金中出现粗大的杆状Al3Zr化合物,导致细化晶粒效果减弱。固溶处理后,合金中过饱和的初生α′树枝晶转变为细小的(α+η)两相组织,少量ε-CuZn5相存留于α晶界上。Zr含量为0.2%的合金中α晶粒变得更加均匀、细小。此外,Zr变质可以显著提高ZA27合金时效处理的峰值硬度,并延迟了对应的时效时间。
ZA27 alloy ingot containing 0.2% or 0.5% Zr was prepared,and the prepared alloy was treated by solid solution at 370 ℃ for 12 hours and artificial aging at 100℃.The results show that 0.2% Zr can apparently modify the ZA27 alloy by transforming developed dendrite into fine rosette grain,however,0.5% Zr content can fade the modification effects as a result of generation of coarse rod-like Al3Zr phase.After solid solution treatment,supersaturated primary α',phase is transformed into fine(α+η) phase in the alloy,meanwhile,a little CuZn5 phase is found in α grain boundary.α grain in the alloy with 0.2% Zr addition exhibits more uniformity and fine.In addition,Zr modification can significantly improve the peak hardness of the aged alloy,and postpone the corresponding aging time at 100 ℃.
出处
《特种铸造及有色合金》
CAS
CSCD
北大核心
2011年第5期476-479,391-392,共4页
Special Casting & Nonferrous Alloys
基金
重庆市重点科技攻关项目(CSTC2008AA4028)
西南大学研究生重点课程建设基金项目(Z2008011)
