Life consumption rate creeping deformation life evaluation method null a little more than

摘要

PROBLEM TO BE SOLVED: To improve residual lifetime estimation accuracy by calculating accurately a creep strain rate, in a residual lifetime estimation method of a metal material utilizing the creep strain rate.;SOLUTION: In this residual lifetime estimation method of the metal material utilizing the creep strain rate, the creep strain rate is calculated by a product of dislocation mobility, an effective stress and a movement dislocation density. The dislocation mobility is determined beforehand from a negative elongation behavior generated at the sudden reduction time of a stress in a stress sudden-change test wherein the stress is suddenly changed during a creep test, and the effective stress is determined beforehand from the relation between a change of the creep strain rate during a time before and after sudden increase of the stress in the stress sudden-change test and the suddenly changed stress, and the movement dislocation density is determined from the relation between the change of the creep strain rate during the time before and after sudden increase of the stress in the stress sudden-change test and the suddenly changed stress, and from the dislocation mobility determined from the negative elongation behavior generated at the sudden reduction time of the stress. In addition the movement dislocation density is correlated beforehand quantitatively with a deposit distribution at that point of time, and determined from the deposit distribution on an estimation part.;COPYRIGHT: (C)2006,JPO&NCIPI