摘要
用扫描电镜背散射电子成像技术 ,对经Zr变质处理的ZA2 7合金在半固态温度 46 0℃部分重熔过程中的微观组织进行了观察 ,并对有关组织的成分进行了测定。结果表明 ,随着保温时间的延长 ,晶界处的共晶组织向初生晶内部扩散 ,趋于消失 ,晶粒由铸态时的等轴晶变为粒状晶。当保温 10min时 ,未来得及溶入的共晶组织开始熔化 ,使组织分离为近粒状。到 2 0min时 ,初生晶粒演变为粒径为 40 μm左右的球状颗粒 ,同时 ,晶粒中细小、弥散分布的 η相由外到里逐渐长大 。
Using the technology of SEM backscattered electron image,the microstructures of ZA27 alloy modified by Zr was investigated during partial remelting at 460℃,and the compositions of some structures were also examined by EDXA.The results indicated that the eutectics between primary grain boundaries diffused toward the grains'cores,and the eutectic layers tended to disappear,which made the primary grains change from the as\|cast equiaxed grains to particle grains.When isothermally treated for 10min,the remaining eutectics that did not resolved into the primary grains began to melt,led the structure separating into particles.When the isothermal time was up to 20min,the primary grains changed into spheroids.Simultaneously,the fine η phases in the primary grains grew up from the outside to the inside of the grains and then remelted.
出处
《材料科学与工程》
CAS
CSCD
北大核心
2002年第1期47-50,共4页
Materials Science and Engineering
基金
甘肃省重点攻关资助项目 (GS992 A52 0 2 4 ) .
