GRADIENT FUNCTION PART AND PRODUCTION METHOD THEREOF

摘要

PROBLEM TO BE SOLVED: To provide a gradient function part which shows necessary softness in parts requiring toughness and necessary hardness in parts requiring hardness.SOLUTION: A method of producing a gradient function part is for production of a gradient function part composed of an age precipitation hardening type alloy and comprises executing a first aging treatment of softening a gradient function part beyond the peak age hardness so that the whole of the gradient function part shows a first hardness lower than the peak age hardness, or the maximum hardness, and then executing a second aging treatment of melting a part of the gradient function part to an extent that the part reaches or approaches the peak age hardness higher than the first hardness and equal to a second hardness lower than the peak age hardness.