Microstructure characteristics of Ti-43Al alloy during twin-roll strip casting and heat treatment

作     者：Mang XU Guo-huai LIU Tian-rui LI Bing-xing WANG Zhao-dong WANG 徐莽;刘国怀;李天瑞;王丙兴;王昭东

作者机构：State Key Laboratory of Rolling and AutomationNortheastern UniversityShenyang 110819China 

出 版 物：《Transactions of Nonferrous Metals Society of China》 (中国有色金属学报（英文版）)

年 卷 期：2019年第29卷第5期

页      面：1017-1025页

核心收录：

学科分类：080503[工学-材料加工工程] 08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0802[工学-机械工程] 080201[工学-机械制造及其自动化] 

基　　金：Project(51504060) supported by the National Natural Science Foundation of China Projects(2016YFB0301201,2016YFB0300603) supported by the National Key Research and Development Program of China Project(N160713001) supported by the Fundamental Research Funds for the Central Universities,China 

主　　题：strip casting TiAl alloy sheet fabrication microstructure characterization heat treatment 

摘      要：To shorten the fabrication process of difficult-to-form TiAl sheets, twin-roll strip casting and microstructural control were investigated in Ti-43Al alloy. A crack-free sheet with dimensions of 1000 mm × 110 mm × 2 mm was obtained. The microstructure of stip casting sheets and heat treatments was systematically studied. The macrostructure consisted of columnar crystals extending inward and centrally located equiaxed crystals with severe Al segregation were observed along the thickness direction, due to the symmetrical solidification process and decreasing cooling rates. The strip casting alloy was characterized by fine duplex microstructure with a grain spacing of 20-30 μm and a lamellar spacing of 10-20 nm. Furthermore, multiple microstructures of near gamma, nearly lamellar and fully lamellar were obtained through heat treatment process with significantly improved homogeneity of the microstructure.