Five-axis machining is a numerical control machine tool processing mode that can realize positioning and connection on five degrees of freedom, including three moving axes x, y, and z plus any two rotating axes. Compared with the common three-axis machining, five-axis machining can better handle the machining problems of complex curved surfaces, such as body parts with free-form surfaces in the aerospace field, turbine parts and impellers. The machine tools used in five-axis machining are usually called five-axis machine tools or five-axis machining centers. Five-axis machining center is based on the three-axis machining center, adding two degrees of freedom, which can realize positioning and connection in three-dimensional space. Its structure mainly includes the following parts: 1. Machine tool bed and table: The bed is the basic part of the five-axis machining center. It usually adopts high-quality cast iron or steel structure to ensure its rigidity and stability. The table usually includes a fixed table and a mobile table for clamping workpieces. 2. Spindle head: The spindle head is one of the key parts of the five-axis machining center. It usually adopts a high-precision and high-rigidity structure, which can realize high-speed and high-precision machining. The movement of the spindle head can be carried out on three coordinate axes, and it can be moved around two rotating axes at the same time. 3. Numerical control system: The numerical control system is the control core of the five-axis machining center, which can realize high-precision and high-speed machining. Usually use advanced numerical control system, such as FANUC, SIEMENS, etc. 4, Tool magazine and tool changing device: Tool magazine is another important part of the five-axis machining center, used to store various tools needed in the machining process. Tool changing device can realize automatic tool changing and improve machining efficiency. 5, Drive system: Drive system is another key part of the five-axis machining center, used to realize the movement of each axis of the machine tool. Usually use high-precision, high-rigidity servo motor and lead screw drive system. 6, guard device: Five-axis machining center is usually equipped with guard devices, used to protect the operator and the machine itself. Including protective cover, guardrail, etc. In short, the structure of the five-axis machining center includes the machine tool bed and worktable, spindle head, numerical control system, tool magazine and tool changing device, drive system and protective device. The reasonable design and cooperation of these parts can achieve efficient and high-precision machining.