| 摘要 |
PROBLEM TO BE SOLVED: To provide a product quality inspection method which inspects quality of a surface-treated product with high reliability in a non-destructive manner at a low cost.SOLUTION: A product quality inspection method includes: a preliminary step which acquires, in advance, a correlation between a depth of a nitride layer from a surface of a sampled product and a value of an X-ray diffraction angle 2&thetas;, at least, uses a nitride layer depth determination criterion D including the depth of the nitride layer at least for evaluating a surface later state, and sets a first diffraction angle threshold Dc1 as a value of the diffraction angle 2&thetas;corresponding to a tolerance Da of the value of the preset nitride layer depth criterion D; a first step which acquires a measurement value of a diffraction angle 2&thetas; of a portion of the nitride layer to be measured, in the product where the surface layer state is to be measured, by means of the X-ray diffraction method; and a second step which determines the quality of a surface layer state of the product to be measured, on the basis of a relation between the measured diffraction angle 2&thetas; obtained in the first step and the first diffraction angle threshold Dc1. |
