半固态A356合金重熔加热时初生相的组织演变  

Microstructure Evolution of Primary Phase in Semi-solid A356 Alloy during Reheating

作　　者：刘政[1] 胡咏梅[2] 

机构地区：[1]江西理工大学机电工程学院,江西赣州341000 [2]江西理工大学工程研究院,江西赣州341000

出　　处：《有色金属科学与工程》2010年第5期18-23,共6页Nonferrous Metals Science and Engineering

基　　金：江西省自然科学基金资助项目(0650047);江西省教育厅科技项目(GJJ09229)

摘　　要：利用低过热度浇注技术制备了半固态A356铝合金坯料,研究了半固态温度区间重熔加热时半固态A356铝合金坯料的初生相形貌的转变过程.结果表明,在半固态两相区保温,半固态A356合金的初生相逐渐团球化,该过程随保温温度的升高而加快.半固态A356铝合金晶粒的圆度与保温温度和保温时间的关系不大,但晶粒的尺寸随着保温温度和保温时间的增加而增大.半固态A356合金试样重熔加热最佳工艺制度为583℃下保温30min,其晶粒平均等积圆直径为80μm,晶粒平均圆度为0.83.This paper studies the transform course for primary phase morphology of the semi-solid A356 alloy billet,produced by low superheat pouring during reheating in solid-liquid phase region.The results indicate that the primary phase of semi-solid A356 alloy is gradually spheroidized during the holding in solid-liquid phase region,in which spheroidization is speeded up with the increase of the holding temperature.There is little effect of holding temperature and holding time on grain roundness of semi-solid A356 alloy,but the grain size of the alloy increases with increasing of the time and the temperature.The optimizing reheating technology of semi-solid A356 alloy is that the billit is held 30 min at 583℃,in which the average equal-area-circle grain diameter is 80μm,and the average grain roundness is 0.83.

关 键 词：半固态 A356铝合金 重熔加热 组织演变 

分 类 号：TF821[冶金工程—有色金属冶金] TG146[一般工业技术—材料科学与工程]