Studies on the Fatigue Performance of Wire and Arc Additive Manufactured SS 904L

Abstract

To understand the complete potential of Wire Arc Additive Manufacturing (WAAM), it is required to explore the relationship between process, the resultant microstructure, and mechanical integrity of the components. WAAM process has achieved a significant attention because of the possibility of fabricating small-medium metal components. Most of the structures made by WAAM process are exposed to cyclic loads and the fatigue performance of WAAM components compared to wrought and cast alloys is far less understood. In the present work, single layered wall was produced via Gas metal arc welded (GMAW) based WAAM process. The wall dimensions were 200 × 145 × 6 mm before machining and 180 × 135 × 3.5 mm after machining, respectively. Fatigue specimens were prepared from the wall component along the built direction. The fatigue characteristics of the WAAM processed 904L samples were correlated to their microstructure as well as the mechanical properties. The fractographs were captured to reveal the fracture morphology. Recent works on WAAM process along with the several influencing parameters on the fatigue behaviour reveals the need for thorough understanding of the fatigue performance of steel structures by this technique. Based on this fact, some of the gaps are discussed in relation with microstructure and mechanical properties for future research in WAAM process.