Characterization on the Precipitates in the Ti-Ni-Al-Zr Alloy during Heat Treatment

Abstract:

In the present paper, the Ti-15Ni-6Al-2Zr alloy is fabricated and heat treated at different temperatures. Its microstructure and morphology of Ti₂Ni phase are investigated by SEM and TEM. The results reveal that the Ti-15Ni-6Al-2Zr alloy is composed of eutectoid and eutectic microstructure, which possesses fine Ti₂Ni fiber in eutectoid region and fine α-Ti phase in eutectic region. With the increase of heat treatment temperature, the amount of α-Ti and Ti₂Ni phases decrease gradually. When the heat treatment temperature is higher than 900°C, almost no α-Ti phase is left. The transformation temperature of α-Ti phase to β-Ti phase is about 850°C, and the transformation of α-Ti phase promotes the decrease of Ti₂Ni phase. During the heat treatment, the Ti₂Ni fiber phase experiences the refining, fragmentation, coarsening and granulating.

• Periodical: Applied Mechanics and Materials (Volumes 727-728)
• Pages: 103-106
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.727-728.103
• Online since: January 2015
• Authors: Li Yuan Sheng*, Fang Yang, Ting Fei Xi
• Keywords: Grain Boundary, Microstructure, Ti₂Ni, Ti-Ni-Al-Zr Alloy

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