Effect of Quenching Temperature on Microstructures and Tensile Properties of PM Ti-23Al-17Nb Alloy

Abstract:

After treated with different quenching processes near transition temperature of orthorhombic phase, PM Ti-23Al-17Nb alloys with different microstructures were obtained. Microstructures of the alloy were observed by optical microscope, and tensile properties were also tested. In order to analyze the relationship between microstructures and tensile properties at room temperature, fractures of broken test bars obtained in tensile tests were characterized by SEM. The results show that quenching process below transition temperature of orthorhombic phase has few effects on improvement of size and morphology of crystal grain. However, it may lead to an abnormal growth of partial crystal grain, which results in low tensile strength and poor ductility; Quenching process above transition temperature of orthorhombic phase can cause recrystallization of B₂ phase, which make a remarkably improvement on size and morphology of crystal grain. Moreover, the alloy performs the max tensile strength of 1026 MPa and the max ductility of 5.8% after quenched at the temperature of 1020

• Periodical: Advanced Materials Research (Volume 279)
• Pages: 10-15
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.279.10
• Online since: July 2011
• Authors: Ze Bao Lang, Xu Hu Zhang, Liang Wang, Wen Jun Jia
• Keywords: Microstructure, Quenching Temperature, Tensile Properties, Ti₃Al Based Alloy

References

[1] H. Jiang: Development of new materials for aerospace structures abroad. Aerospace Materials & Technology, 4(1998), pp.1-8.

[2] T. Lan, C. Han, B. Zhang, M. Li, Y. Zhao, H. Qu: Investigation of PM Ti-14Al-21Nb. Rare Metal Materials and Engineering, 21, 3(1992), pp.53-58.

[3] C. F. Yolton, J. P. Beckman: PM processing and properties of the ordered orthorhombic alloy Ti-22at.%Al-23at.%Nb. Materials Science Engineering A, 192/193(1995), pp.597-603.

DOI: 10.1016/0921-5093(94)08283-9

[4] Z. Lang, X. Zhang: PM Processing and Properties of Ti-23Al-17Nb. Chinese Journal of Rare Metals, 32, 6(2008), pp.709-713.

[5] T. Lan, B. Zhang, X. Liu and Y. Zhao: Forming of PM Ti-14Al-21Nb alloy by HIP. PM Technology, 11, 3(1993), pp.184-188.

[6] S. Li, Y. Mao, J. Zhang, J. Li, Y. Cheng, Z. Zhong: Effect of microstructure on tensile properties and fracture behavior of intermetallic alloys. Trans. Nonferrous Met. Soc. China, 12, 4(2002), pp.582-586.

[7] Y. Zhang, J. Liu, J Zhang: Microstructure transition and tensile properties of Ti-22Al-25Nb intermetallic alloy forged in β-phase zone. Nonferrous Met. Soc. China, 18, 1(2008), pp.30-35.

[8] Y. Wu, D. Yang: An investigation of microstructure of Ti3Al-Nb alloy. Material Science and Technology, 4, 4(1996), pp.48-52.