Plastic Deformation and Creep Damage Measurement by Intra-Granular Distortion Analysis

摘要

A method of intra-granular distortion (IGD) analysis for measuring deformation as developed using a transmission electron microscope (TEM). Creep and tensile deformation levers crystal bend and torsion (distortion) in polycrystalline materials, with can be quantitatively calculated by the orientation change in crystals using the Kikuchi pattern shift vector. Good correlation between deformation amount and distortion were obtained in SUS304 stainless and 2.25Cr-1Mo steels. This method was adapted for evaluating the creep damage of 2.25Cr-Mo steel in fossil fuel power plants in terms of creep deformation. It was calculated that 2.25Cr-1Mo boiler tube for 220 000 hours has spent nearly 70 percent of the service life.