摘要
通过常规力学性能、扫描电镜、透射电镜等测试分析方法研究了T8I6二次时效制度对Mg、Ag和Zn复合微合金化的Al-3.48Cu-1.44Li合金微观组织和力学性能的影响。结果表明,与单级时效相比,二次时效合金强度提高,而塑性略降;合金强度随第三级时效时间的延长进一步提高。最优的合金其抗拉强度(UTS)、屈服强度(YS)和延伸率分别为613.7、564.9 MPa和6.8%。合金的强化相主要为T1相,另有少量的θ'相和S'相。二次时效促进强化相,特别是T1相的二次沉淀,提高合金的强度,同时几乎不损失塑性。
The microstructure and mechanical properties of a Mg, Ag and Zn micro-alloyed A1-3.48Cu-1.44Li （wt%） alloy treated by 3＇816 secondary aging were investigated by means of normal mechanical property test, scanning electron microscope（SEM） and transmission electron microscope（TEM）. The results showed that, the strength of secondary aging alloy is improved and the elongation is slightly lowered compared with single aging alloy; the strength increased further with the third stage aging prolonging. The strengthening phases of the experimental alloy are mainly T1 precipitates with minor θ＇ and S＇ precipitates. The UTS, YS and elongation of the optimum alloy are 613.7,564.9 MPa and 6.8%, respectively. The secondary aging promoted the formation of aging precipitates, especially T1 precipitates, which improved the strength. Meanwhile, the elongation of the alloy with T816 secondary aging is almost not lowered.
出处
《宇航材料工艺》
CAS
CSCD
北大核心
2014年第5期50-54,60,共6页
Aerospace Materials & Technology
基金
国家高技术研究发展计划(863计划)资助项目(2013AA032401)
