ESTIMATION METHOD OF STRESS CORROSION CRACK OF ACTUAL STRUCTURE AND LEFT LIFE ESTIMATION METHOD

摘要

PPROBLEM TO BE SOLVED: To provide a method for estimating a process up to the formation of a surface crack having a detectable dimension by the production union and development of fine surface cracks at the contact surface with a corrosion environment of a structural material present under arbitrary stress distribution and a process up to the formation of a larger crack by the subsequent development and union of cracks and a method for estimating the left life of an actual structure on the basis of an estimate result. PSOLUTION: The data related to the production union and development behavior of fine surface cracks are acquired with respect to the small-sized test piece in a laboratory acceleration test of the structural material and an actual structure environment. These data are used as input data and the production of the fine surface cracks being the stress corrosion crack in the actual structure is set as a probability process and the union and development of the fine surface cracks are set as a decision process to perform computer simulation. As the result of the simulation, the SCC life until reaching a limit surface crack is obtained as statiscal quantity and the left life from the present point of time of the actual structure is estimated. PCOPYRIGHT: (C)2007,JPO&INPIT