Production and analysis of additively manufactured SS316L using Direct Metal Laser Sintering (DMLS) technique based on hybrid Taguchi-Grey grade relational analysis

Abstract

Metal Additive Manufacturing is a state-of-the-art technique with unique capabilities for developing highly precise functional parts. Direct Metal Laser Sintering (DMLS) is an advanced 3D metal printing process used to create metal parts for various applications, including marine, aerospace, and automotive. Due to its excellent mechanical and corrosion resistance properties, Stainless Steel (SS316L) is widely used in marine and chemical environments. Therefore, DMLS is implemented to precisely develop SS 316 L parts. The layer-by-layer development of the DMLS process is influenced by various process variables. In this investigation the DMLS process variables considered for the fabrication process include Laser Power (LP), Scan Speed (SS), Hatch Distance (HD), and Layer Thickness (LT), each with three levels. The experimental design Taguchi L9 Orthogonal Array (OA) is considered to fabricate SS 316 L samples in accordance with ASTM standards. The quality of the manufactured parts is analyzed based on performance characteristics such as Ultimate Tensile strength (UTS), Hardness (H), surface roughness (R_a) and wear loss (WL). A Multi-Criteria Decision Making (MCDM) technique called Hybrid Taguchi-Grey Relational Grade Analysis (T-GRGA) is employed to optimize the DMLS process variables. The T-GRGA conformity results revealed an improvement in the percentage of tensile strength, hardness, surface roughness and wear Loss. ANOVA is used for identifying the significant DMLS process variables affecting the performance characteristics. The response plots were employed to identify the interaction effects between the process variables and performance characteristics. The T-GRGA optimum conditions sample resulted and also evidence of microstructure revealed by Field emission - Scanning Electron Microscope (FE-SEM).