OS0710 無酸素銅の非比例多軸低サイクル疲労寿命(OS7-2 解析・評価・き裂I,OS-7 多軸応力下における疲労損傷および疲労き裂進展1)

抄録

This paper presents the nonproportional low cycle fatigue life for oxygen-free high conductivity copper. Strain controlled tension-torsion low cycle fatigue tests were performed using hollow cylinder specimens under four strain paths: push-pull, torsion, combined tension-torsion and 90 deg. out-of-phase strain paths. Fatigue lives under circular path were smaller than those under the other three strain paths at the same Mises equivalent strain ranges. The difference in fatigue lives was discussed in relation to the additional hardening effect in nonproportional loading. Applicability of maximum principal strain and nonproportional strain was discussed to evaluate multiaxial low cycle fatigue lives.