Metastable phase separation and rapid solidification of undercooled Co_(40)Fe_(40)Cu_(20) alloy  

作　　者：Xiaojun Bai Yaocen Wang Chongde Cao 白晓军;汪姚岑;曹崇德(1 Research and Development Institute ofNorlhwestern Polytechnical University in Shenzhen, Shenzhen 518057, China 2Department of Applied Physics, Northwestern Polytechnical University, Xi＇an 710072, China)

机构地区：[1]Research and Development Institute of Norlhwestern Polytechnical University in Shenzhen, Shenzhen 518057, China [2]Department of Applied Physics, Northwestern Polytechnical University, Xi'an 710072, China

出　　处：《Chinese Physics B》2018年第11期305-309,共5页中国物理B（英文版）

基　　金：Project supported by the National Key Research and Development Program of China(Grant No.2016YFB1100101);the National Natural Science Foundation of China(Grant No.51471135);Shenzhen Science and Technology Program,China(Grant No.JCYJ20170815162201821);Shaanxi Provincial Key R&D Program,China(Grant No.2017KW-ZD-07);the Fundamental Research Funds for the Central Universities,China(Grant No.31020170QD102)

摘　　要：The metastable liquid phase separation and rapid solidification behaviors of Co_（40） Fe_（40） Cu_（20） alloy were investigated by using differential thermal analysis（DTA） in combination with glass fluxing and electromagnetic levitation（EML） techniques. The critical liquid phase separation undercooling for this alloy was determined by DTA to be 174 K. Macrosegregation morphologies are formed in the bulk samples processed by both DTA and EML. It is revealed that undercooling level, cooling rate, convection, and surface tension difference between the two separated phases play a dominant role in the coalescence and segregation of the separated phases. The growth velocity of the（Fe,Co） dendrite has been measured as a function of undercooling up to 275 K. The temperature rise resulting from recalescence increases linearly with the increase of undercooling because of the enhancement of recalescence. The slope change of the recalescence temperature rise versus undercooling at the critical undercooling also implies the occurrence of liquid demixing.The metastable liquid phase separation and rapid solidification behaviors of Co_（40） Fe_（40） Cu_（20） alloy were investigated by using differential thermal analysis（DTA） in combination with glass fluxing and electromagnetic levitation（EML） techniques. The critical liquid phase separation undercooling for this alloy was determined by DTA to be 174 K. Macrosegregation morphologies are formed in the bulk samples processed by both DTA and EML. It is revealed that undercooling level, cooling rate, convection, and surface tension difference between the two separated phases play a dominant role in the coalescence and segregation of the separated phases. The growth velocity of the（Fe,Co） dendrite has been measured as a function of undercooling up to 275 K. The temperature rise resulting from recalescence increases linearly with the increase of undercooling because of the enhancement of recalescence. The slope change of the recalescence temperature rise versus undercooling at the critical undercooling also implies the occurrence of liquid demixing.

关 键 词：UNDERCOOLING metastable phase separation rapid solidification IMMISCIBILITY 

分 类 号：O4[理学—物理]