Method for producing a reference piece for the X-ray measurement of a residual stress and a reference piece for the X-ray measurement of a residual stress

摘要

[Object] The object of the present invention is to offer metallic material other than a strain-free iron powder as a reference piece for the X-ray measurement of a residual stress. [Means for solving the problem] The problem is solved in that after nano-crystallization of at least a part of the surface of a metallic material, the stress can be relieved by removing the inherent strain by annealing.