3D printing (additive manufacturing) builds a part by adding material according to a digital 3D model. Unlike milling or turning, which remove stock, additive processes grow the shape layer by layer.
For metals, a common approach is LPBF—laser powder bed fusion. A thin layer of metal powder is spread across the build plate; a laser traces the slice geometry and selectively melts particles so they fuse with the layer below. The cycle repeats until the part is complete.
Key advantages include design freedom (internal channels, lightweight lattices, topology-optimized shapes), a short path from design to the first physical sample, and economical small batches without expensive tooling. Trade-offs include the need for supports on overhangs, possible post-machining of critical surfaces, and careful CAD preparation (wall thickness, thermal stress, feature connectivity).
Final properties depend on the alloy (stainless steel, titanium, aluminum, and others), part orientation, and process parameters. For demanding applications, heat treatment is often applied according to material standards and end-use requirements.