Material properties and mechanical behaviour of large-scale additively manufactured multi-layered steels

Abstract

Metal Big Area Additive Manufacturing is an additive manufacturing technique based on gas metal arc welding. The systems’ dual nozzle design prints two steels simultaneously; in this study, the test samples are made from AISI 410 stainless steel and AWS ER70S-3 mild steel. Three print patterns were designed to isolate the effects on the interface between the two materials. Deformation behaviour was analyzed by the use of two-dimensional digital image correlation. Nonhomogeneous strains and Lüders banding within the mild steel directly adjacent to the SS-MS interface were observed. There is a clear increase in strength close to the interface but no statistical change in strength between print patterns. Acicular ferrite/bainite were found close to the interface and allotriomorphic ferrite into the mild steel. A possible explanation for the changes in microstructure from is discussed by the use of electron diffraction spectroscopy, digital image correlation, microhardness, and electron backscatter diffraction.