摘要
研究了ZA2 7合金在应力诱发熔体激活法 (SIMA)处理过程中形变量和等温温度对组织的影响。结果表明 :在 2 50℃预变形时 ,随着形变量的增加 ,ZA2 7合金的原始组织由发达的树枝状晶逐渐演变为粗化的等轴晶和短树枝状晶 ;在等温处理中 ,形变量越大和等温温度越高 ,初生α相逐渐形成球状颗粒 ;低温下 ,ZA2 7合金组织粒状化的原因是回复与再结晶的多边形晶界处形成低熔点Zn Al Cu三元共晶组织 ,较高温度则形成Zn Al二元共晶。
The influences of strains and isothermal temperatures on microstructure of ZA27 alloy during strain\|induced melt activation (SIMA) were investigated.The results indicated that with the increase of strain at 250℃,the raw structure of ZA27 alloy changed from developed dendrites to coarse equiaxial grains and short dendrites.The greater the strain and the higher the temperature,the easier the primary α phase spheriodizing of ZA27 alloy was.The cause of α phase spheriodizing was the formation of low melt point Zn\|Al\|Cu ternary eutectic at grain boundaries due to recovery and re\|crystallization at lower temperature and Zn\|Al binary eutectic at higher temperature.
基金
甘肃省中青年科技基金!资助项目 (YS981 A2 2 0 0 5 )
关键词
SIMA
球状化组织
等温温度
锌合金
形变量
ZA27 alloy strain
\ isothermal
\ strain\|induced melt activation
\ spheriodizing structure
