Effect of Defect Depth on Rotational Bending Fatigue Properties of Laser Remanufactured Samples of 30CrMnSiA Steel

The fatigue samples of 30CrMnSiA high strength steel with 0. 15 mm and 0. 55 mm preset defect depth were repaired by manual laser surfacing technology. Then the rotational bending fatigue properties of the samples were tested and the fatigue fracture was analyzed. The results show that the fatigue properties of samples with defect depth of 0. 15 mm were closed to those samples without defect under low stress condition, however, with the increase the depth of defect, the fatigue properties decreased significantly. With the increase of stress level, there were more and more fatigue cracks, which made the fracture easier.