Microstructure Transformation of a Refined High Nb Containing TiAl Alloy

Abstract:

High Nb containing TiAl alloys have been investigated traditionally as potential high temperature structural materials because of their high strength, good oxidation and creep resistance. However, the poor ductility and fracture toughness at room temperature limit their application, which could be improved by controlling microstructure to get refine and homogeneous fully lamellar structure. In this study, a high Nb containing TiAl alloy alloying Mn, B and Y with refined microstructure was produced. The solidification path was analyzed by DSC and SEM microstructure of the alloy was observed, after heating at a certain temperature for 1-24hrs and then quenching in water. The dissolution of β phase was also investigated. The results showed that the β phase could decompose only by heating in single β or near α phase field.

• Periodical: Materials Science Forum (Volumes 747-748)
• Pages: 38-43
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.747-748.38
• Online since: February 2013
• Authors: Li Hua Chai, Liang Yang, Jian Peng Zhang, Zhi Yong Zhang, Lai Qi Zhang, Jun Pin Lin
• Keywords: Dissolution of β Phase, Heat Treatment, High Nb-TiAl Alloy, Microstructural Transformation

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