2012 年 12 巻 2 号 p. 101-106
Stress distribution of prismatic bar with 8mm square cross section was measured using the grain growth in an electrodeposited copper foil. The copper foil was adhered to the prismatic bar subjected to cyclic bending-torsion loading. A Schenck-type fatigue testing machine was used, and tests were performed at a frequency of 60 Hz by mounting the bending-torsion fixture in the test machine. The crystallographic orientations of individual grains that undergo grain growth in the foil were analyzed by electron backscatter diffraction (EBSD). Since the grain orientation was controlled by the cyclic stress, {110} pole figure and orientation imaging microscopy (OIM) mapping in an area of 0.18-0.25 mm2 were used for measuring the distribution of biaxial stress ratio on a surface of the prismatic bar. Stress distributions obtained by both methods agreed well with the theoretical solution. It was clarified that he method using {110} pole figure can measure the principal stress more accurately than the method using OIM mapping.
