FATIGUE AND RESIDUAL LIFE EVALUATION OF MECHANICAL PART

摘要

PURPOSE:To increase the accuracy of detecting fatigue and damage, by determining the depth of a damage range according to a (half-amplitude level ratio)/(depth from surface) graph from a data of a half-amplitude level of an X-ray diffraction intensity curve on a surface to be inspected to be compared with a data of (depth of damage range)/(fatigue damage) previously determined from a separate test piece. CONSTITUTION:A surface layer of a mechanical part to be inspected is ground finely to form a surface to be inspected, a data of a half-amplitude level is determined on an X-ray diffraction intensity curve for a surface being inspected while a depth d0 of a damage range is determined from a graph of H/H0 (half- amplitude level ratio)/(depth from surface) and fatigue and residual life are judged from a fatigue damage based on a data of d0 (depth of damage range)/D (fatigue damage) determined from a separate test piece and a microscopic crack observed on the very skin of the surface being inspected near both ends thereof. In other words, an X-ray diffracting device is composed of an X-ray generation tube 1, a slit 2 and a detector 3 and transmits a detection signal from the detector 3 to a computer 6, a control signal of which 6 is transmitted to a driving section of a mobile plate 4 and the detector 3.