Microstructure transition of Al-Cu eutectic alloy during containerless rapid solidification  

作　　者：LU Yongjun, WANG Nang and WEI Bingbo(Laboratory of Materials Science in Space, Department of Applied Physics, Northwestern Polytechnical University, Xi’an 710072, China) 

出　　处：《Progress in Natural Science:Materials International》2003年第2期130-134,共5页自然科学进展·国际材料（英文版）

基　　金：Supported by the National Natural Science Foundation of China (Grant Nos. 50221101, 50101010 and 50071009);Fok Ying-tung Education Foundation (Grant No. 71044)

摘　　要：Droplets of Al-32.7%Cu eutectic alloy were rapidly solidified during containerless processing in a 3 m drop tube. The microstructural evolution of Al-Cu eutectic alloy depends strongly on droplet size. The eutectic growth morphology changes from regular lamellar eutectic to a kind of anomalous eutectic with the decrease in droplet size. This microstructural transition was analyzed within the current theories of eutectic growth. The results indicate that there exists a critical velocity for eutectic growth beyond which anomalous eutectic appears. The coupled zone of the Al-Cu eutectic alloy system has been calculated on the basts of the Trivedi-Magnin-Kurz(TMK) eutectic growth and the Lipton-Kurz-Trivedi(LKT)/Boettinger-Coriell-Trivedi(BCT) dendrite growth models, which provides a further interpretation for the morphological transition.Droplets of Al-32.7%Cu eutectic alloy were rapidly solidified during containerless processing in a 3 m drop tube. The microstructural evolution of Al-Cu eutectic alloy depends strongly on droplet size. The eutectic growth morphology changes from regular lamellar eutectic to a kind of anomalous eutectic with the decrease in droplet size. This microstructural transition was analyzed within the current theories of eutectic growth. The results indicate that there exists a critical velocity for eutectic growth beyond which anomalous eutectic appears. The coupled zone of the Al-Cu eutectic alloy system has been calculated on the basis of the Trivedi-Magnin-Kurz(TMK) eutectic growth and the Lipton-Kurz-Trivedi(LKT)/Boettinger-Coriell-Trivedi(BCT) dendrite growth models, which provides a further interpretation for the morphological transition.

关 键 词：Al-Cu alloy crystal growth MICROSTRUCTURE phase transition. 

分 类 号：TG146.2[一般工业技术—材料科学与工程]