Understanding of laser shock peening on AM components

• Main Author: Lam, Markus Wen Chuan
• Other Authors: Sridhar Idapalapati
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2024
• Subjects: Engineering; LSP; DED; Interlayer LSP
• Online Access: https://hdl.handle.net/10356/177287
• Institution: Nanyang Technological University

Laser shock peening (LSP) is a process that was developed as a substitution for conventional shot peening. It is a surface treatment that is used to improve fatigue life and wear resistance of metallic parts. For the purpose of this study, the materials that will be used is Inconel 625 and Inconel 718. Inconel 625. Inconel 625 and Inconel 718 is one of the most utilized nickel-based superalloys, primarily due to its strong weldability and versatility in processing different manufacturing techniques. The primary distinction lies in the fact that Inconel 625 offers superior corrosion resistance, whereas Inconel 718 is better suited for applications requiring high strength. In this project, different parameters of LSP are utilized on Inconel 718 before Directed Energy Deposition of Inconel 625 (DED) is done on half of the LSP-ed surface. This study investigates the effects of directed energy deposition on various parameters of laser shock-peened Inconel 718. DED is an additive manufacturing process in which focused thermal energy is used to fuse materials by melting as they are being deposited. For the purpose of the experiments, 6 samples of Inconel 718 were prepared. 5 of the samples were LSP-ed under different parameters and 1 of the samples was kept as it is. DED is done on half of the LSP-ed surface. The samples were subjected to a series of tests aimed at gathering data on various parameters, including surface profile, residual stress, wettability, hardness, and microstructure.