Solidification Behavior and Microstructures Characteristics of Ti-48Al-3Nb-1.5Ta Powder Produced by Supreme-Speed Plasma Rotating Electrode Process  

作　　者：Zhenbo Zuo Rui Hu Xian Luo Qingxiang Wang Chenxi Li Zhen Zhu Jian Lan Shujin Liang Hongkui Tang Kang Zhang 

机构地区：[1]State Key Laboratory of Solidification Processing,Northwestern Polytechnical University,Xi’an,710072,China [2]Sino-Euro Materials Technologies of Xi’an Co.,Ltd.,Xi’an,710018,China

出　　处：《Acta Metallurgica Sinica(English Letters)》2023年第8期1221-1234,共14页金属学报（英文版）

基　　金：financially supported by the Key R&D Program of Shaanxi(Program No.2022GY-388).

摘　　要：In this study,the characteristics and solidification behavior of Ti-48Al-3Nb-1.5Ta powder produced by supreme-speed plasma rotating electrode process(SS-PREP®)were investigated.The microstructure,phase and characteristics were analyzed by scanning electron microscopy,X-ray diffraction and other methods.The atomization mechanism is direct drop formation.The relationship between the particle size and cooling rate is vc=3.14×10^(-7)·d^(-2)+1.18×10^(-2)·d^(3/2),and the relationship between secondary dendrite arm space and the particle size isλ=0.028d+0.11,as well as the relationship between SDAS and cooling rate isλ=4.84×10^(-5)·T^(-1.43).With increase in particle size,the surface structure gradually changes from the featureless smooth structure to dendritic and cellular dendritic morphology,and the flow ability becomes better.The carbides mainly exist within 5 nm of the surface and the oxidation layer is about 20 nm thick.Ti-48Al-3Nb-1.5Ta powder was mainly composed ofα2 phase andγphase.With increase in particle size,the content ofγphase increases,and the hardness decreases accordingly.The 106–250μm particles are composed of multiple grains with the grain size of 70–80μm.The microstructure,phase composition and hardness of different TiAl powders with the same size are similar,but the elastic modulus is different.

关 键 词：Supreme-speed plasma rotating electrode process(SS-PREP) TiAl alloy Atomization POWDER Microstructure 

分 类 号：TG142.71[一般工业技术—材料科学与工程]