The Correlation between Microstructure and Dynamic Mechanical Property of Heat Treated Β20C Titanium Alloy Based on Different Forging Processes

Abstract:

As a new material, the microstructure of β20C titanium alloy can match well with property by forging process. However, the microstructure of billet is inhomogeneous in actual forging. For ensuring microstructures homogenization, two forging processes are designed. Process 1 is large deformation above the phase transition (T=1050°C, 70% deformation) and small deformation in two-phase region (T=860°C~890°C, ≤40% deformation). Process 2 is small deformation above the phase transition (T=1050°C, 40% deformation) and large deformation in two-phase region (T=860°C~890°C, 50%~60% deformation). Then microstructures are observed and dynamic compressive strength and the critical fracture strain of samples are test after solid-solution treatment. It turns out that the homogeneity of microstructure of process 2 is improved by heat treatment. The microstructure is lamellar microstructure with 1650MPa dynamic strength and 15% critical fracture strain through “Process 1 + 840°C 1h/FC” while the microstructure is equiaxed microstructure with 1650MPa dynamic strength and 20% critical fracture strain through “Process 2 + 840°C 1h/FC”. In conclusion, the microstructure of large deformation in two-phase region can accumulate more deformation energy which is beneficial for dynamic recrystallization.

• Periodical: Applied Mechanics and Materials (Volume 782)
• Pages: 71-76
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.782.71
• Online since: August 2015
• Authors: Li Rui Huo, Qun Bo Fan, Rui Hua Gao, Fu Chi Wang
• Keywords: Dynamic Mechanical Property, Forging, Heat Treated, β20C Titanium Alloy

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