Mg-8%Al-2%Ga镁合金的形变热处理  

Thermo-Mechanical Treatment of Mg-8%Al-2%Ga Magnesium Alloy

作　　者：孙晶[1] 李常金 刘云秋[1] 郭全英[1] 毛萍莉[1] 刘正[1] 

机构地区：[1]沈阳工业大学材料科学与工程学院,辽宁沈阳110870

出　　处：《铸造》2014年第4期317-321,共5页Foundry

基　　金：辽宁省科技攻关计划(2013201018);辽宁省高校创新团队支持计划资助

摘　　要：用扫描电镜、X射线衍射仪等分析手段及布氏硬度测试,研究了形变热处理对Mg-8％Al-2％Ga合金组织及力学性能的影响.结果表明,Mg-8％Al-2％Ga合金轧制变形方式以孪生为主;轧制变形后在150～300℃退火时,未发生再结晶,硬度的变化规律是随着退火时间的延长,硬度值先下降,然后上升,达到峰值后基本不变;150～200℃退火时,仅在晶界及孪晶处析出细小、弥散的β相,300℃退火时,在晶粒内部还观察到沿基体α相的（0001）晶面析出的长条状β相及一些菱形片状彼此夹角为120°（60°）的β相;400℃退火时,发生了再结晶,硬度值明显低于前三个温度.The influence of thermo-mechanical treatment on microstructure and mechanical properties of Mg-8% AI-2%Ga alloy has been investigated by means of scanning electron microscopy, X-ray diffraction analysis and the Brinell hardness test. The results show that the rolling deformation of Mg-8%Al-2%Ga alloy is mainly deformed by twinning. By annealing at 150-300 ℃, after rolling deformation, recrystallization has not been examined and the variation of hardness with annealing is that the hardness values decreased at the first stage and then increased, basically unchanged after the peak. After annealing at 150-200 ℃, only small and dispersed β phase precipitates at the grain boundaries and twins boundaries. By annealing at 300 ℃, long strip β phase along the crystal plane （0001） of matrix a phase and some diamond-shaped β phase with an angle of 120° （60° ） of each other are also observed inside the grains. After annealing at 400 ℃, recrystallization is observed and the hardness value is obviously lower than the previous three temperatures.

关 键 词：镁合金 轧制 变形 孪生 组织 力学性能 再结晶 β-Mg17Al12相 

分 类 号：TG166.4[金属学及工艺—热处理]