Effects of Heat Treatment on Microstructures and Properties of Ti811 Alloys

Abstract:

Mechanical properties and microstructures of Ti811 alloys under different heat treatment conditions were studied. The results show that the microstructures of Ti811 alloy consist of α, massive β and grain-boundary β after normal annealing. The intensity and hardness decreased, while the ductility increased. After double annealing, the primary phase α reduced and needle-like secondary α〞 was formed. The massive β and grain-boundary β changed into intergranular β gradually. The microstructure was relatively uniform. Then the intensity and hardness increased, the ductility decreased when compared to general annealing. The needle-like secondary α〞and metastable β would break down into dispersed α and β after solution hardening and aging. The combination properties of alloys would be improved. According to fractography of titanium alloy, the fracture mechanism of the Ti811 alloy was dissociation - brittle intergranular fracture, which was a type of fracture between the intergranular fracture of brittle and cleavage fracture.

• Periodical: Applied Mechanics and Materials (Volumes 117-119)
• Pages: 1032-1035
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.117-119.1032
• Online since: October 2011
• Authors: Hui Gai Wang, Fei Wang, Yan Pei Song
• Keywords: Heat Treatment, Microstructure, Ti811 Alloy

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