Fatigue-strength Properties of Welded-joints of High-strength Weldable Structural-steel

Particularly with regard to weld joints, high-strength and super high-strength structural steels under unfavourable boundary conditions is hardly superior to normal-strength steel. These studies aim at analyzing whether the fatigue strength characteristics of butt joint and cruciform joint samples can be improved by optimizing the weld seam geometry and by subsequent mechanical treatment by shot peening with ceramic balls or with steel scraps, and at determining which difficulties may occur during this process. The practical tests were supported and completed by theoretical calculations according to the FE-method. A final comparison with the standards will illustrate the difficulties in determining admissible fatigue strength values of weld joints.