To provide a Ti alloy which has high strength, high fatigue strength and reduced hardness and is suitable as a material for various structures including automobiles, and a method for producing the same.
An alloy of which a processing starting structure is an α' martensite phase is subjected to hot working. It is heated at a temperature-rising rate of 50-800°C/sec, a strain rate is at 0.01-10/sec in a temperature range of 700 to 800°C and is at 0.1-10/sec in a temperature range of higher than 800°C and lower than 1,000°C, and the strain is 0.5 or greater. In this manner, the titanium alloy having equiaxial crystals whose average crystal grain diameter is smaller than 1,000 nm is obtained which has high strength and high fatigue resistance properties, has a hardness of less than 400 HV and tensile strength of 1,200 MPa or more, and has excellent static strength and dynamic strength.
ONO YOSHIKI
MATSUMOTO HIROAKI
CHIBA MASAHIKO
UNIV TOHOKU
| JP4766408B2 | 2011-09-07 |
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