Improvement Of Ni 18 (250) Maraging Steel Weldment Fatigue Strength Through Shot Peening

Author:  Banas, G. and Lawrence,Jr., F.V.
Source:  Conf Proc: ICSP-3, (p.675-680)
Doc ID:  1987045
Year of Publication:  1987
Abstract:  
The low fatigue strength of weldments limits the design stresses of welded components. Fortunately, the fatigue strength of weldments can be substantially increased by shot peening and by other post-weld treatments which alter the severity of the critical notch, increase the notch root material's fatigue resistance (strength), or induce favorable residual stresses at the notch root. This study investigated the effects of various shot peening treatments on the fatigue resistance of groove weldments in thin gauge (3 mm) sheets of a maraging steel fatigued under reversed bending. The results of the experiments were compared with two analytical models for the fatigue strength of weldments. Comparison of theory with experiment lead to the conclusion that not all shot peening treatments cause substantial improvements in the fatigue resistance of weldments.