NON-DESTRUCTIVE DETECTION METHOD OF HIGH TEMPERATURE FATIGUE DAMAGE REGION

摘要

PROBLEM TO BE SOLVED: To detect a fatigue damage concentrated region in a non-destructive manner before a crack occurs by fatigue under a high temperature environment without preforming a data base related to the correlation between deterioration quantity and an evaluation parameter.;SOLUTION: This non-destructive detection method of a high-temperature fatigue damage region includes a step (a) for cooling a specimen (austenite stainless steel receiving fatigue damage under a high-temperature environment of 450-800°C) to a room temperature or below, a demagnetizing step (b) for removing residual magnetism, a magnetizing step (c) for applying an external magnetic field and a step (d) for measuring magnetic characteristics and the steps (a)-(d) are repeated at a plurality of the different points of time. The temporal difference distribution of magnetic characteristics is calculated from the obtained measuring result or a region where magnetic characteristics continuously change monotonously calculated to specify the fatigue damage concentrated region.;COPYRIGHT: (C)2006,JPO&NCIPI