Research On Five-axis NC High Efficient Machining Technology For UAV Thin-walled Impeller

Integrated Impellers are a type of representative parts with a relatively normal sculptureshape and a complex structure. The design of the working surface relates to several subjects suchas aerodynamics, hydrodynamics and so on. Factors such as manufacture means, machiningprecision and machining quality of the surface all have large effect on the capability parameters.The integral impeller has the characteristics of thin-walled parts, blending twist blade, smallinterval between adjacent blades. And it is a key component of aero engine turbine machineryand all kinds of other turbo machinery. Now with the development of the science and technology,the requirements of the performance of the engine were increasing. It has great difficulties in itsmanufacturing process because of the structural characteristics of integral impeller. Five axis NCmachine tools have the advantages of good flexibility, wide working range, and high processingefficiency. So it is one of the most commonly used methods for machining of integral impellerusing five axis NC machining.The main contents and achievements of this paper are as follows:1. According to the process characteristics of integral impeller, the formulation of processflow was decided in detail. And by selecting the appropriate machine tools, efficient cutting tools,reasonable cutting parameters, a solid foundation for machining an impeller can be obtained.2. In rough machining stage, the comparative analysis of two kinds of processing strategies(leaf disc area clearance process and the3+2fixed shaft processing method) was finished. Andultimately it was determined which processing scheme is more efficient in practice.3. In the environment of VERICUT software, machine tool model can be created by usingsame related parameters of DMG five axis high-speed CNC machining center in the lab. Thewhole milling process of impeller was simulated, allowing the operator to see the visual motionstate of machine tool manufacturing process. Therefore it can exclude the interferencephenomenon that may occurred in programming and verify the reliability of processingprocedures. So it is possible for optimizing the machining process, saving processing time, andimproving production efficiency.4. Before NC machining, the cutting parameters like the spindle speed, cutting speed andcutting force was determined by using the method of multi-objective optimization method. Andthe optimal combination of cutting parameters can be obtained by genetic algorithm. Finally theimpeller was processed on the machine and we can check it by using Geomagic Qualify software.Then the feasibility and correctness of the impeller machining process was verified.The study on high accuracy and high efficiency five-axis NC machining of thin-walledimpeller is accomplished and has a favorable value in the engineering application. In addition, the result of the research can be applied in five-axis machining of other sculptured surfaces forreference.