| 摘要 |
PROBLEM TO BE SOLVED: To provide a titanium alloy component by using a method for improving the degradation of the fatigue strength caused by rough surface of and hydrogen infiltration in the surface of the titanium alloy component subjected to the plasma carburization. SOLUTION: After a bolt stock formed of a titanium alloy is subjected to solution and aging treatment, the bolt stock is subjected to the plasma carburization in the temperature range of 350-700°C, and in the pressure range of 10-2,000 Pa. After the plasma carburization, the stock is re-heated in the temperature range of 150-350°C under the argon atmosphere so as to be screw form-rolled. By performing the screw form rolling after the plasma carburization, the form rolling effect can be maintained, such that a work-hardened layer of a bottom part of a thread in which a fatigue fracture is easily generated is not softened, the compressive stress is not mitigated, and the rough surface caused by the plasma carburization is smoothed, and the fatigue strength of the titanium alloy screw component can be improved. COPYRIGHT: (C)2007,JPO&INPIT
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