FRACTAL ANALYSIS OF FRACTURE SURFACE OF WELDING JOINT UNDER LOW CYCLE FATIGUE
焊接接头材料低周疲劳断口的分形分析

Hausdorff dimension of fracture surface roughness of welding joint, both weld metal and heat-affected zone, of pressure vessel steel 16MnR, tested under strain-controlled low-cycle fatigue, was examined with computer vision system and by two-dimensional variation method. Results show that it decreases with the increase of cyclic hysteresis energy. The Hausdorff dimension variation at heat-affected zone is higher than that of weld metal. It is believed that the higher the fractal dimension is, the longer the fatigue life will be.