A Study on the Fatigue Growth Behavior of Surface Cracks -Prediction of Crack Aspect Ratio under the Constant Amplitude Tension Fatigue Loads-

표면균열의 피로성장거동연구 -인장 반복 하중하에서의 균열형상비 예측-

The fatigue growth behavior of surface cracks cannot be adequately predicted solely by stress intensity factor analysis. This is caused by different plastic deformation due to variations in the stress field triaxiality along the crack tip. Therefore, a new model which accounts for the crack closure phenomenon is proposed in this paper to predict the fatigue crack growth patterns for surface cracks. Fatigue tests were performed to develop the new model for the prediction and to assess the accuracy of the analysis. The predicted crack growth behavior for PMMA and Aluminum alloy 7075-T6 materials agreed well with the experimental data.