Numerical Simulation of Selective Laser Melting of 304 L Stainless Steel

Abstract

This paper used the smoothed particle hydrodynamics (SPH) method to construct a three-dimensional mathematical model of the selective laser melting (SLM) process of 304 L austenitic stainless steel. Important driving force models for the melt pool in the SLM process were developed, including a surface tension model, a boundary normal-modified wetting effect model, a Marangoni shear force model, and a recoil pressure model. Meanwhile, the virtual particle boundary method prevented particles from flying over the solid boundary. Artificial viscosity, artificial stress, and artificial heat were added to correct the SPH equation, which provided a guarantee for the accuracy and speed of the numerical simulation of the SLM process. Finally, the temperature field and velocity field in the SLM process were explored according to the constructed mathematical model. The evolution mechanism in the melting process was analyzed, and the influence of different laser powers on the shape of the molten pool was mainly analyzed, which provided a reference for optimizing the laser parameters to reduce the surface roughness of the formed specimen.

Recycled PET Composites Reinforced with Stainless Steel Lattice Structures Made by AM

“…An SLM cylinder made of 316L stainless steel (sample S3) has a compression strength of 47 MPa (Figure 5a). Similar aspects were reported in the literature [23,24]. The reinforced sample (S4) proved to be stronger than the bare SLM structure, resulting in a compression strength of 53 MPa.…”

Surface Roughness of Interior Fine Flow Channels in Selective Laser Melted Ti-6Al-4V Alloy Components

“…When the layer thickness was increased to 50 µm at a laser power of 120 W, the depth of the melt pool increased and the stair-step effect became more prominent. This condition limited powder splashing, but the heat may not have been able to fully penetrate and evenly distribute throughout the thicker layer, potentially leading to uneven melting and increased channel surface roughness [ 96 ]. Therefore, the channel surface roughness at a layer thickness of 50 µm was observed to be higher than that at a layer thickness of 20 µm because the deeper melt pool at the larger layer thickness also favored the entrapment of gases, contributing to increased porosity and lowering the density [ 94 ].…”