Effect of heating temperature and cooling rate on the microstructure and mechanical properties of a Mo-rich two phase α + β titanium alloy

Abstract Mechanical properties of the two-phase titanium alloy Ti6Al7Nb, after the heat treatment based on soaking this alloy in the α + β range, cooling in water or oil and ageing at two selected temperatures, were determined in the hereby paper. The alloy mechanical properties were determined in tensile and impact tests, supported by the fractographic analysis of fractures. In addition, its hardness was measured and the analysis of changes occurring in the microstructure was performed for all variants of the alloy heat treatment. Regardless of the applied cooling rate of the alloy, from a temperature of 970°C followed by ageing at 450 and 650°C, none essential changes were noticed in its microstructure. It was shown that applying less intensive cooling medium (oil) instead of water (before tempering) decreases strength properties indicators, i.e. tensile strength and yield strength as well as hardness (only slightly). The decrease of the above mentioned indicators is accompanied by an increase of an elongation and impacts strength. Fractures of tensile and impact tests are of a ductile character regardless of the applied heat treatment.

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Microstructure and Mechanical Properties of X80 Induction Heating Bends

Materials Science Forum ◽

10.4028/www.scientific.net/msf.762.158 ◽

2013 ◽

Vol 762 ◽

pp. 158-164

Author(s):

Liu Qing Yang ◽

Yu Liu ◽

Bin Feng ◽

Yu Ran Fan ◽

Deng Zun Yao

Keyword(s):

Mechanical Properties ◽

Cooling Rate ◽

Induction Heating ◽

Heating Temperature ◽

Tensile Tests ◽

Granular Bainite ◽

Metallographic Analysis ◽

Good Strength ◽

Microstructure And Mechanical Properties ◽

Strength And Toughness

By using physical thermal simulation technology, combined with metallographic analysis, tensile tests, impact and hardness tests, effects of heating temperature and cooling speed on microstructure and mechanical properties of X80 induction heating bends were investigated. The results show that as the heating temperature rises, TS of X80 induction heating bends increases gradually. However, when the heating temperature rises above 1100°C, plasticity and toughness of the bends begin to decrease, and grain growth tends to be obvious. When the heating temperature is 1050°C, X80 induction heating bends have a good strength and toughness. As the cooling rate increases, strength and toughness of X80 bends are improved considerably. In the cooling rate range between 20°C/s and 30°C/s, the microstructure of X80 bends is mainly composed of polygonal ferrite and granular bainite. Due to the very high dislocation density inside granular bainite and the fine and dispersed M-A constituents, X80 induction heating bends have a very good strength and toughness.

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Microstructure and mechanical properties of TC4 titanium alloy K-TIG welded joints

Transactions of Nonferrous Metals Society of China ◽

10.1016/s1003-6326(21)65506-1 ◽

2021 ◽

Vol 31 (2) ◽

pp. 416-425

Author(s):

Shu-wan CUI ◽

Yong-hua SHI ◽

Cheng-shi ZHANG

Keyword(s):

Mechanical Properties ◽

Titanium Alloy ◽

Welded Joints ◽

Tc4 Titanium Alloy ◽

Microstructure And Mechanical Properties

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Effects of Cold-Rolling Reduction on Microstructure and Mechanical Properties of Ti50Zr30Nb10Ta10 Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.849.376 ◽

2016 ◽

Vol 849 ◽

pp. 376-381

Author(s):

Ming Long Li ◽

Yu Jie Geng ◽

Chen Chen ◽

Shu Jie Pang ◽

Tao Zhang

Keyword(s):

Mechanical Properties ◽

Titanium Alloy ◽

Plastic Strain ◽

Cold Rolling ◽

Reduction Ratio ◽

High Fracture ◽

Dendrite Structure ◽

Microstructure And Mechanical Properties ◽

Cold Rolling Reduction ◽

Cold Rolled

The effects of cold-rolling with different reduction ratios of 70%-90% on the microstructure and mechanical properties of Ti50Zr30Nb10Ta10 alloy were investigated. It was found that the β-Ti phase in this alloy was stable under cold-rolling. With the increase in reduction ratio from 70% to 90%, the microstructure of the alloys evolved from deformed dendrite structure to fiber-like structure. The alloy cold-rolled with the reduction ratio of 70% exhibited optimum mechanical properties of combined high fracture strength of 1012 MPa and plastic strain of 10.1%, which are closely correlated with the dendrite structure of the alloy. It is indicated that the proper cold-rolling is an effective way to improve the mechanical properties of the titanium alloy.

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