Effect of changing material deposition order on mechanical properties in bimetals of aluminum bronze and duplex stainless steel by wire and arc directed energy deposition

Abstract Many attempts have been made to improve functionality by controlling the mechanical and thermal properties through the use of multi-materials in components. In this study, bimetallic structures of aluminum bronze and duplex stainless steel were deposited by wire and arc directed energy deposition, focusing on the control of elastic deformation properties by combining materials with different Young’s modulus. Controlling the elastic deformation requires an understanding of the Young’s modulus distribution at the material interface; however, this has not been investigated. It is also possible that the material deposition order influences penetration at the interface and changes the Young’s modulus distribution; however, the specific effects are unknown. Therefore, in this study, bimetallic structures with different material deposition orders were deposited, and the results were compared using crystallographic phase analysis by etching, elemental diffusion analysis by EDX, and tensile tests using digital image correlation. The results showed that the Young’s modulus near the interface exhibited a gradient distribution, and the magnitude of the gradient depended on the material deposition order. This is considered to be due to the variation in the Young’s modulus associated with changes in the crystalline phase due to the material deposition order. This study shows that there is a means to consider the effect of the material deposition order on the Young’s modulus distribution to improve the accuracy of elastic deformation control.