Abstract: Multi-axis Computer Numerical Control (CNC) machining is an iconic manufacturing technology in modern industry, which dominates the manufacturing of key components in the fields of energy, power, national defense, vehicles, aerospace, etc. In these fields, the requirement for high-end equipment is strict, so that a large number of precision and complex curved parts with considerable machining difficulty and tight performance tolerances have emerged. The machining requirements for these parts have been evolving from simple shape and position accuracy in the past towards high performance requirements that place equal emphasis on accuracy and performance. This brings severe challenges to the traditional CNC machining technology for complex curved parts. The state of the art and difficulties of the key technical issues such as accuracy guarantee, improvement of machining efficiency and control of the dynamic cutting process are discussed in terms of tool path planning, feedrate scheduling and dynamics analysis of CNC machining processes. Then, the feasible routes, breakthrough direction and future development trend are also expounded, so as to provide an effective reference and guidance for high performance machining of precision complex curved parts.

Key words: complex surface, CNC machining, tool path, feedrate, machining dynamics