Abstract

In fatigue life prediction, it is important that fatigue life is affected by crack closure phenomenon in thin sheet Al alloy. In this research, we attempt to (l)analyze the characteristics of fatigue crack propagation in constant loading condition for thin sheet Al 2024-T3 alloy which is generally used in transportation structures, (2)identify the crack closure phenomenon in thin sheet comparing experimental results of thin and thick sheet specimen under same fatigue loading condition. In using the fatigue related material constants from these fatigue crack propagation analysis, we attempt to (3)operate the fatigue life estimating process with considering crack closure phenomenon and (4)analyze the experimental and prediction results offatigue life in thin sheet AI alloy.

• Keywords: Fatigue crack propagation(피로균열전파),Fatigue crack growth rate(피로균열성장률),Crack closure phenomenon(크랙닫힘현상),Image method(이미지방법),Automatic measurement(자동측정),C-language(C-언어)