Residual stress measuring apparatus and residual stress measuring method

A residual stress measuring method for measuring residual stress of a measuring object using a residual stress measuring apparatus equipped with an X-ray generating source, a first detecting element adapted to detect an intensity of diffracted X-rays of the measuring object at a first detecting position, a second detecting element adapted to detect an intensity of the diffracted X-rays of the measuring object at a second detecting position different from the first detecting position, and a moving mechanism adapted to move each of the first detecting element and the second detecting element along a straight line extending in a direction orthogonal to a direction of incidence of the X-rays, the residual stress measuring method comprising:

• an X-ray irradiation step of radiating X-rays toward the measuring object;
• a movement control step of moving the first detecting element and the second detecting element by driving the moving mechanism, wherein each of the first detecting element and the second detecting element moves such that a relative distance between the respective detecting positions of the first detecting element and the second detecting element and a position where the X-rays are irradiated changes;
• and
• a stress calculation step of calculating residual stress of the measuring object based on intensity peaks of the diffracted X-rays of the measuring object detected, respectively, by the first detecting element and the second detecting element during execution of the movement control step.