Effect of solution treatment on microstructure and properties of TC11 titanium alloy

doi:10.13251/j.issn.0254-6051.2023.02.030

Abstract

Abstract: Relationship between microstructure and mechanical properties of the TC11 titanium alloy after solution treatment at 955, 975, 995 and 1015 ℃, respectively, was studied by means of optical microscope, scanning electron microscope, X-ray diffraction and room temperature tensile test. The results show that the original as-forged microstructure of the alloy is a bimodal structure formed by forging in the α+β two-phase region, which is dominated by α_p phase and β transformation structure. After solution treatment, the twisted and elongated α_p phase in the original as-forged structure gradually becomes smaller and rounded with the increase of solution treatment temperature, and the smaller α_p phase gradually disappears. When the solution treatment temperature is 995 ℃, the strengths of the alloy reach the maximum, of which the tensile strength (R_m) is 1403 MPa and the yield strength (R_p0.2) is 1158 MPa. When the solution treatment temperature is 955 ℃, the plasticity of the alloy is the best, of which the elongation after fracture (A) is 9.5% and the percentage reduction of area (Z) is 32%. When the solution treatment temperature is in the two-phase region, the tensile fracture morphology is similar, which is mainly dimples. When the solution treatment temperature is in the single-phase region, the fracture morphology is obviously crystalline and has large tearing edges, and there are a large number of small tearing dimples on the rock-like surface.

Key words: TC11 titanium alloy, solution treatment, microstructure, mechanical properties, fracture morphology

CLC Number:

TG156.1

Tong Xiaole, Zhang Mingyu, Yue Xu, Yang Bin, Wang Yujia, Ardak Almas. Effect of solution treatment on microstructure and properties of TC11 titanium alloy[J]. Heat Treatment of Metals, 2023, 48(2): 195-199.

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