Effect of Cr/Mo on Microstructure and Mechanical Properties of Ti-Al-Nb Alloy

Abstract:

Effects of alloying elements (i.e., variable content of Mo and C) on the microstructure and compression properties of four types of experimental material based on TiAl-based alloy containing 8 at.% Nb were investigated. The specimens were prepared by vacuum noncollapsable melting technology and followed by a homogenization treatment with air cooling. The compression properties at room and at elevated temperature were evaluated in laboratory air. The results demonstrate that the inter-lamellar space of the alloy decreased with the addition of the Cr and Mo alloying elements. Cr acts a better role in grain refinement, while Mo enhances the content of γ phase in the alloys. The addition of Cr/Mo elements improves the elastic modulus of the material, but reduces the breaking strength due to the absence of the dislocation region found in non-Cr / Mo alloys that resist cracking. The concentrated distribution of γ phase at grain boundaries hinders recrystallization and the tendency of grain orientation.

• Periodical: Materials Science Forum (Volume 936)
• Pages: 178-186
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.936.178
• Online since: October 2018
• Authors: Zhu Hang Jiang, Ning Li, Cheng Zhi Zhao*, He Xin Zhang, Zhi Ming Li
• Keywords: Compression Behaviors, Cr/Mo Alloying, High Nb, Microstructure, TiAl-Based Alloy

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