SLM (Selective Laser Melting) is a metal 3D printing technology that uses a high-energy laser beam to melt metal powders (e.g., stainless steel, aluminum alloy, titanium alloy) layer by layer, forming parts through cooling and solidification. With a typical layer thickness of 20–100μm, it achieves high precision (within ±0.05mm) and complex geometric structures, producing parts with mechanical properties close to forged components, widely used in high-precision, high-strength fields like complex aerospace components, custom medical implants, and lightweight automotive structural parts.