Microstructural effects on properties of additively manufactured Inconel 625 and 718

Abstract

Three Dimensional(3D) printing is known as additive manufacturing: it is a method of manufacturing parts or components form sheet, wire or powder in a manufacturing process. This method differs from traditional manufacturing techniques such as casting, moulding or subtracting materials which already exist. The type of material characterization is also very important in the development and improve or manufacturing of new materials for higher strength and various application. Selective Laser Melting(SLM) an additive manufacturing powder-based process has been adopted by automotive and aerospace industries. The reason for this is that it has many potential benefits, such as 3D designs of complex components in a shortened time frame, which offers financial savings. SLM process use metallic powders with different chemical composition to manufacture complex structures, which is an innovative material processing technology. In this research SLM, a typical additive manufacture process method, was used to manufacture additively manufactured Inconel 625 and 718. These sample specimens were investigated to determine their microstructural features and mechanical properties. The microstructural features were characterized using two different experimental surface microscopy methods: scanning electron microscope(SEM) and light optical microscope (LOM). The mechanical properties were determined by studying deformation and hardness characteristics using three-point bending and hardness tests. The relationship between processing, microstructure, grain sizes and mechanical properties was established. The understanding of SLM additive manufacturing of alloys is important as well for the adoption of the technology, and the possibility of replacing commercially produced cast and wrought alloys in the near future.