摘要
通过拉伸试验、金相观察、扫描电镜、透射电镜等手段研究了不同双级固溶处理对2A14铝合金力学性能及组织的影响。结果表明:双级固溶获得了较高程度的过饱和固溶体,仅发生了部分再结晶;最佳双级固溶工艺为:470℃×2 h+510℃×1 h,采用该工艺并经160℃×8 h时效后,合金的拉伸力学性能达到σb=508.4 MPa,σ0.2=422.7 MPa,δ=14.9%;经双级固溶后,Al2Cu相已基本完全溶解,未溶相主要为富含Fe、Si的杂质相,其拉伸断口呈现出典型的韧窝型断裂;时效后合金中的主要强化相为S′相,且在470℃×2 h+510℃×1 h二级固溶并时效后的析出相较单级固溶的数量更多且细小均匀,因而获得了更高的析出强化效果。
The effects of different two-stage solution treatments on mechanical properties and microstructure of 2A14 aluminum alloy were researched by means of tension test, metallographic observation, SEM and TEM. The results show that the higher over-saturated solid solution is obtained by the two-stage solid solution, and only part recrystallization happens; the optimal two-stage solution process is 470 ℃×2 h＋510 ℃×1 h; using this process and then 160℃×8 h aging, tensile mechanical properties of the alloy σb, σ 0.2 and δ reach 508.4 MPa, 422.7 MPa and 14.9%, respectively; after two-stage solution, Al2Cu phase is almost completely dissolved, the undissolved phases are mainly inclusions with rich Fe and Si, and the tensile fracture shows a typical ductile fracture; the main strengthening phase in the alloy after aging is S＇ phase, and the precipitates are much more, finer and more uniform after the two-stage solution of 470 ℃×2 h＋ 510 ℃×1 h than those of the single stage solution.As a result, a better precipitation strengthening effect is attained.
出处
《热加工工艺》
CSCD
北大核心
2017年第4期207-211,共5页
Hot Working Technology
基金
国家重点基础研究发展规划项目(2012CB619504)
高性能复杂制造国家重点实验室自由探索项目(zzyjkt2014-02)
关键词
2A14铝合金
双级固溶
力学性能
组织
2A14 aluminum alloy
two-stage solution
mechanical properties
microstructure
