EBSDを用いた銅めっき層の初期疲労損傷に関する研究

概要

論文の詳細を見る
Early fatigue damage in electrodeposited copper was investigated under cyclic torsion and bending. First, the angle between longitudinal direction of the specimen and the fatigue slip line that occurred at the foil surface was measured after a cyclic loading test. The angle was also calculated from the crystal orientation analyzed by using electron backscatter diffraction. The calculated angle agreed well with that obtained from the experimental results. This means that the fatigue slip line occurs from the slip system with high Schmid factor in electrodeposited copper. Second, the relationship between Schmid factor and slip direction was calculated for the crystal that the fatigue slip line occurred in a cyclic torsion test. Finally, the crystallographic feature of crystals which a fatigue crack tends to nucleate was analyzed by EBSD. The number of cycles to form a slip line and the fatigue crack initiation tended to be controlled not only by Schmid factor but also by the slip direction.