Effects of heat treatments on microstructures of TiAl alloys

Wen Yu; Jianxin Zhou; Yajun Yin; Zhixin Tu; Xin Feng; Hai Nan; Junpin Lin; Xianfei Ding

doi:10.1007/s12613-021-2252-z

Volume 29 Issue 6

Jun. 2022

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Article Navigation > International Journal of Minerals, Metallurgy and Materials > 2022 > 29(6): 1225-1230

Wen Yu, Jianxin Zhou, Yajun Yin, Zhixin Tu, Xin Feng, Hai Nan, Junpin Lin, and Xianfei Ding, Effects of heat treatments on microstructures of TiAl alloys, Int. J. Miner. Metall. Mater., 29(2022), No. 6, pp. 1225-1230. https://doi.org/10.1007/s12613-021-2252-z

Cite this article as:

Wen Yu, Jianxin Zhou, Yajun Yin, Zhixin Tu, Xin Feng, Hai Nan, Junpin Lin, and Xianfei Ding, Effects of heat treatments on microstructures of TiAl alloys, Int. J. Miner. Metall. Mater., 29(2022), No. 6, pp. 1225-1230. https://doi.org/10.1007/s12613-021-2252-z

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Research Article

Effects of heat treatments on microstructures of TiAl alloys

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Corresponding authors:
Jianxin Zhou E-mail: zhoujianxin@hust.edu.cn

Xianfei Ding E-mail: xianfeimail@gmail.com
Received: 24 November 2020; Revised: 6 January 2021; Accepted: 15 January 2021; Available online: 16 January 2021

Abstract

Abstract

This study aims to investigate the effects of heat treatments on the microstructure of γ-TiAl alloys. Two Ti–47Al–2Cr–2Nb alloy ingots were manufactured by casting method and then heat-treated in two types of heat treatments. Their microstructures were studied by both optical and scanning electron microscopies. The chemical compositions of two ingots were determined as well. The ingot with lower Al content only obtains lamellar structures while the one higher in Al content obtains nearly lamellar and duplex structures after heat treatment within 1270 to 1185°C. A small amount of B2 phase is found to be precipitated in both as-cast and heat-treated microstructures. They are distributed at grain boundaries when holding at a higher temperature, such as 1260°C. However, B2 phase is precipitated at grain boundaries and in colony interiors simultaneously after heat treatments happened at 1185°C. Furthermore, the effects of heat treatments on grain refinement and other microstructural parameters are discussed.
- TiAl alloys;
- microstructure;
- heat treatment;
- casting

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