Precipitation of Ti 2 Al phases at lamellar interfaces in a high-Nb-containing TiAl alloy during thermal exposure  

作　　者：Dongxu Li Guoying Zhang Gang Lu Yujie Liu Jianjun Wang Chunming Liu 

机构地区：[1]Key Laboratory for Anisotropy and Texture of Materials(MOE),School of Materials Science and Engineering,Northeastern University,Shenyang 110819,China [2]College of Physics Science and Technology,Shenyang Normal University,Shenyang 110034,China [3]Research Center for Metallic Wires,Northeastern University,Shenyang 110819,China

出　　处：《Journal of Materials Science & Technology》2022年第31期132-140,共9页材料科学技术（英文版）

基　　金：support provided by the National Natural Science Foundation of China(NSFC)(No.51371049).

摘　　要：The thermal stability of microstructures is crucial for determining the performance of alloys in extreme environments.In the present work,the microstructural evolution and precipitation behavior in a high Nb-containing Ti45Al8Nb alloy during thermal exposure at 950°C were investigated.It was found that excessα2 phases in the as-cast microstructure were unstable and tended to decompose during thermal expo-sure.Hexagonal Ti 2 Al phases precipitated at lamellar interfaces and had a[1¯10]_(γ)[11¯20]_(α2)[11¯20]_(Ti2Al),(002)_(γ)(1¯100)_(α2)(1¯100)_(Ti2Al)crystallographic orientation relationship(OR)with the matrix.Stacking faults(SFs)generated inα2 phases during theα2→γphase transformation provided favorable nucleation sites for Ti 2 Al phases.

关 键 词：TiAl alloy Thermal exposure Phase transformation PRECIPITATION 

分 类 号：TG146.23[一般工业技术—材料科学与工程]