Characterization of a low-alloy steel component produced with wire arc additive manufacturing process using metal-cored wire

Abstract

Abstract In this study, a low-alloy steel component was manufactured using specially produced E70C-6M class of metal-cored welding wire according to AWS A5.18 standard for the WAAM process. The manufactured low-alloy steel component was first subjected to radiographic examination to detect any weld defect. Uniaxial tensile tests were conducted for the bottom, middle and upper regions. The micro-hardness tests were performed parallel to the deposition direction. The results show that microstructures varied from base metal to the face region of the WAAM component, including the bottom, middle and top sections. The bottom region showed lamellar structures; the middle and upper region presented equiaxed ferrite structure with a small amount of grain boundary pearlites and the face region displayed a mix of equiaxed and lamellar structures of ferrites. The yield and ultimate tensile strengths of the top, middle, and bottom regions exhibited similar results varying between 370 MPa and 490 MPa, respectively. In contrast, the top region showed an elongation value about 15% higher than other regions. Moreover, the yield and ultimate tensile strength for WAAM-produced component were found to be 14% and 24% lower than the multiple-pass all-weld metal of E70C-6M class of metal-cored wire.