202 切欠きを有するファイバーメタル積層板の非主軸S-N関係とその予測方法(OS6-(1) 複合材料の変形と破壊およびマルチスケール計算技術,オーガナイズドセッション)

Abstract

The effects of notch size and fiber orientation on the off-axis fatigue strength of the notched fiber metal laminate GLARE-3 are examined. Off-axis fatigue tests are performed on notched (center open hole) specimens with different fiber orientations. It is clearly observed that the fatigue strength of notched GLARE-3 exhibits not only notch size dependence but also fiber orientation dependence. A new criterion for the fatighe failure of notched orthotropic materials is developed which allows prediction of their fatigue lives for any notch size and for any multiaxial state of stress. The proposed fatigue failure criterion is an extension of the fatigue damage mechanics model which was earlier developed for unnotched orthotropic materials. A major advantage of the proposed method is to allow efficient prediction of the S-N curves of the notched GLARE-3 laminates using only a limited amount of test data: the notched strengths and the S-N curves for unnotched specimens. It is demonstrated that the off-axis S-N relationship for notched GLARE-3 can accurately be predicted by means of the proposed fatigue failure criterion, regardless of the notch size and fiber orientation.