斜め隅き裂のき裂面部分弾性接触シミュレーションによる残留応力下の疲労き裂伝ぱ挙動の予測

抄録

In residual stress fields, the so-called partial elastic contact of crack surfaces sometimes occurs, where a fatigue crack is closed at the crack mouth while it is open at crack tip. The partial elastic contact has significant effect on the lives of fatigue cracks. However there are few studies on the partial elastic contact of crack surfaces for three-dimensional cracks. In this paper, the propagation paths and lives of slant corner fatigue cracks are predicted by using three-dimensional fatigue crack propagation simulations considering the partial elastic contact of crack surfaces. The finite element method was employed for the simulations. The crack propagation rates obtained by simulations considering the partial elastic contact of crack surfaces differed from those without considering the contact, demonstrating the necessity of simulation considering the partial elastic contact of crack surfaces. However the propagation paths and crack shapes estimated considering the partial elastic contact hardly differed from those without the consideration.