Microstructural Evolutions of a High Temperature Titanium Alloy Processed by Thermal Mechanical Treatments

Abstract:

TG6 alloy is a new titanium alloy which has been designed to reach the service temperature of 600°C. The microstructural evolutions of TG6 alloy under different thermal mechanical treatments were studied. It was found that lamellar microstructures with basketweave α lamella are obtained for TG6 alloy forged in β field. The evolution mechanism is transformed from dynamic recrystallization to dynamic recovery and the thickness of α lamella increases with increasing forging temperature. The aspect ratio of α lamella decreases firstly and then increases with increasing deformation degree. Grain boundary α lath appears when the deformation degree is less than 40%. The thermal mechanical treatments, including deformation in β field firstly and then deformation in α+β field result in the transformations of the microstructures drastically. The deformation degree in α+β field decides the final microstructure. The deformation degree of 20% in α+β field results in partial globular α phase.

• Periodical: Materials Science Forum (Volumes 747-748)
• Pages: 860-865
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.747-748.860
• Online since: February 2013
• Authors: Tao Wang, Hong Zhen Guo, Ze Kun Yao, Zhang Long Zhao, Shu Hong Fu, Yong Zhang
• Keywords: Deformation Mechanism, Microstructure, TG6 Titanium Alloy, Thermal Mechanical Treatment

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