Additive Manufacturing of Horizontal and 3D Functionally Graded 316L/Cu10Sn Components via Multiple Material Selective Laser Melting

Production of functionally graded materials (FGMs, i.e., a gradual transition from one material to another) and components is challenging using conventional manufacturing techniques. Additive manufacturing (AM) provides a new opportunity for producing FGMs. However, current metal AM technologies including powder-bed fusion are limited to producing single material components or vertical FGM parts, i.e., a different material composition in different layers but not within the same layer, and in situ changing materials is challenging. In this paper, we demonstrate the fabrication of horizontal and 3D 316L/Cu10Sn components with FGM within the same layer and in different layers, via a proprietary multiple selective powder delivery array device incorporated into a selective laser melting system that allowed the deposition of up to six different materials point by point. The manufactured component macrostructure, microstructure, microhardness, and phases were examined. Smooth transition from one material to the other was realized. Also, an interesting phenomenon was found that the maximum hardness was at 50% 316L and 50% Cu10Sn. The work would open up a new opportunity for the manufacturing of true 3D functionally graded components using additive manufacturing and for the rapid development of new metal alloy systems.