1317 超微細粒銅の疲労強度と表面状態(S21-2 疲労破面性状と疲労微視組織の解析,S21 金属材料の疲労特性と破壊機構)

Abstract

Using an ultrafine grained copper processed by ECAP, rotating bending fatigue tests have been carried out. Significant differences in morphological feature in post-fatigued surfaces between high and low cyclic stress amplitudes were observed. To clarify the formation process of surface damage, morphological changes in surface damage caused by cyclic stresses were monitored successively by an optical microscope. Putting those OM observations and SEM observations of post-fatigued surfaces together, the formation processes of surface damage were discussed.