Residual stress variations in substrate (AISI D2) during directed energy deposition process of high-speed tool steel (AISI M4) powder

Abstract

This study aims to observe the residual stress in a substrate and predict stress behavior during the laser deposition process (DED) using finite element analysis (FEA). The residual stress observed on the substrate surface indicated that stress variation during the deposition process increases with proximity to the deposition area, resulting in higher residual stress levels. Additionally, tensile residual stress tends to increase with the height of the deposition area. While variations in the deposition area size influenced the residual stress, consistent stress levels were observed at the same measurement points across different area sizes. The deposition process was simulated using FEA, which confirmed that stress behavior is influenced by melting and solidification cycles. The residual stress levels after cooling aligned well with those observed in actual experiments. Therefore, this study suggests that stress variations can be effectively predicted by simulating the deposition process prior to conducting actual experiments.