Additive Manufacturing (AM), commonly known as 3D printing, combines computer-aided design, material processing and forming technology, based on digital model files, through software and numerical control systems, special metal materials, non-metal materials and medical biological materials , According to extrusion, sintering, melting, light curing, spraying, etc. layer by layer, to manufacture the manufacturing technology of solid objects. Compared with the traditional processing mode of raw material removal-cutting and assembly, it is a "bottom-up" manufacturing method through the accumulation of materials from scratch. This makes it difficult to manufacture complex structural parts that were constrained by traditional manufacturing methods in the past. Additive manufacturing technology refers to a scientific and technological system that directly manufactures parts based on the discrete-stacking principle and is driven by the three-dimensional data of the parts. Based on different classification principles and understanding methods, additive manufacturing technology also has many titles such as rapid prototyping, rapid prototyping, rapid manufacturing, and 3D printing. The connotation is still deepening and the extension is constantly expanding. "Manufacturing" has the same meaning as "rapid prototyping" and "rapid manufacturing". At present, the relatively mature metal additive manufacturing technologies mainly include selective laser melting, laser melting deposition, and electron beam melting, and each process method has a relatively mature product supply market. Now, the best editors of Shenzhen Best introduce these three processes: 1. Selective Laser Melting Selective Laser Melting (SLM) is a 3D model of a workpiece that is layered first, and then uses a scanning system to control the laser beam to treat the material in the forming area Irradiation is performed to selectively melt the metal powder. After the scanning of each slice is completed, the powder feeding system completely covers the formed area with new powder, and repeats these two actions continuously until the scanning of all slices is completed, and the cumulative molding of the workpiece is achieved layer by layer.　　 2. Laser fusion deposition 　　 Laser fusion deposition (LMD) is also called laser direct manufacturing. Generally, a higher-power laser is used, and the feeding method is mostly synchronous powder feeding. Direct stacking deposition is its great technical feature. Compared with the traditional manufacturing process, this method has high flexibility and short process, which can significantly reduce the cost and time of the finished product. It has great potential in the preparation of small batches and high-value metal parts.　　 3. Electron beam smelting 　　 Electron beam smelting (EBM) is a process method in which metal powder is melted and formed by electron beams under high vacuum conditions. Vacuum conditions and electron beams are the main differences between EBM and LMD and SLM. Parts made with EBM technology have good compactness and high strength.