摘要
在高真下，采用熔融玻璃净化与循环过热相结合的方法，在２２～２７０Ｋ过冷度范围内，研究了Ｃｕ７０Ｎｉ３０合金凝固组织形态演化过程，在△Ｔ〈△Ｔ２＾＊（１２０Ｋ）过冷度范围内，随着过冷度增大，枝晶渐变为粒状晶，发生了组织的第一类粒化，组织观察及成分分析结果表明，枝晶段之间偏析区不是晶界。第一粒粒状晶的形成过程包括；枝晶在再辉期间发生熔断，从而形成枝晶段，然后枝晶段通过合并一再结晶而形成粒状晶。
The microstructure evolution of Cu_70Ni_30 alloy melts was systematically investigated in the undercooling range of 21 K to 270 K by using glass fluxing technique combined with cycle superheating and cooling processing in high vacuum. When △T < △T~*_2(120 K), the first granular crystalline formed gradually from dendrite with increasing undercooling. The analysis of microstructure and composition shows that high-angle boundaries do not coincide with the segregation zone between remelted fragments. It is shown that the grain refinement process consists of the disintegration of dendrite formed in rapid solidification and recrystallisation of dendritic fragments.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
2000年第4期351-355,共5页
Acta Metallurgica Sinica
基金
国家自然科学基金!59871041
陕西省自然科学基金!98C13
关键词
深过冷
Cu70Ni30合金
枝晶熔断
再结晶
undercooling, Cu_(70)Ni_(30) alloy, dendrite remelting, recrystallization
