A cyclic biaxial stress measurement method using electrodeposited copper foil was examined. The crystallographic orientations of individual grains that undergo grain growth in copper foil subjected to cyclic loading were analyzed by electron backscatter diffraction (EBSD). An individual grain had the preferred orientation that depended on the biaxial stress condition. One of the grain slip direction corresponded closely to the direction of first principal shearing stress (maximum shearing stress). When the biaxial stress ratio approaches zero, the difference between the first principal shearing stress and the second principal shearing stress gradually becomes small. Therefore, grain orientation under such a condition was influenced by both principal shearing stresses. On the basis of these features, biaxial stress measurement using a pole figure and an orientation imaging map were proposed in this paper. There is a specific restriction in this method. However, the method has excellent resolution compared with other stress-strain measurement methods since it can measure the principal stresses in an area of 500 μm × 500 μm.
