Fatigue Life of Welded Joint Improvement with Various Welding Principles and Shot Peening process for AISI 1020 Low Carbon Steel

Many sheets of low carbon steel AISI 1020 were fitted with dimensions (160×120 x 10 mm) are used in this study. Before welding, some of them are subject to shot peening by steel ball to demonstrate the relationship between pre-shot peening and improvement of mechanical properties. The prepared plates shot and shot less, are welded using Gas Tungsten Arc welding with increasing welding current. Welding joint without faults is chosen for the creation of test specimens. Tensile tests are conducted to measure the state of the fatigue loading. Rotating Bending fatigue, residual stresses, microstructure, and micro-hardness tests were performed. The test results show that the DC current of the welding process and shot peening process improves the mechanical properties of the weld joint by20 %and 21% respectively relative to the base metal. In addition, the fatigue life of welded specimens also increased as a result of the microstructure change and the comparative residual stress created by shot peening.