Strain Distribution Measurement in Stainless Steels by Convergent-Beam Electron Diffraction

Abstract

A convergent-beam electron diffraction technique was utilized to measure local strain distributions in stainless steels. Electron beams were focused into {210} crystal planes and the higher order Laue zone (HOLZ) lines diffracted from {375} and {119} planes were characterized by measuring the distances between the intersections of these HOLZ lines. Four parameters, including strains in three directions and one magnification factor, were calculated based on the least squares method. Strain distributions near a chromium carbide precipitate were measured in sensitized SUS 304 and it was confirmed that parallel tensile strain and vertical compressive strain to the edge of the precipitate existed and that they decreased with the distance from the edge of precipitate.