Research On Five-axis NC Simulation And Processing Parameters Optimization For Aviation Integral Impeller

The processing methods, machining precision and surface quality of the aviation integral impeller have the direct influence of the impeller performance. These factors have a decisive impact on the performance of the engine. As a typical complex high-precision parts, impeller’s blade channel spacing is small. Leaf distortion is large and complex geometric structure which caused great difficulties for processing. Therefore, five axis NC machine tool is used for machining the impeller. Although the machining simulation and parameter optimization of the aviation integral impeller were carried out many studies, but there are still some problems:(1)The optimization study of parameter did not consider the stability of the machine. Carry out the processing parameters on the stability of the optimization of the machine to ensure efficiency and quality of five-axis machining.(2)Due to the large blade twist, the NC program generated by CAM software usually consider the interference of the tool and the workpiece only without the collision of spindle and fixture. It does not guarantee the accuracy of the tool path and machine safety. Therefore, it is necessary to consider the specific process system and more comprehensive geometric simulation analysis. To solve the above problems, the main research work is as follows:1. Establishment of NC simulation model of aero integral impeller based on VERICUT. CNC machine tools, control systems, the magazine and the coordinate system are established in VERICUT, which create CNC simulation environment to achieve specific geometry simulation technology system and effectively avoid the collision among the machine spindle, tool and worktable, fixture.2. The air integral impeller NC program post-processing algorithm of based on the homogeneous transformation is proposed. Firstly, according to the function of the inclined plane in the Heidenhain iTNC530 numerical control system, through the homogeneous transformation operation of the CLSF tool path, the NC program post-processing algorithm is presented. Use UGNX8.5/Post Builder to write post-processing documents. The correctness of the post-processing method is verified through the NC code analysis and VERICUT simulation.3. Acquisition of chatter stability domain of process system based on cutpro9.0. Firstly, machine tool and machine tool workpiece of frequency response function are obtained by the force sensor and an acceleration sensor and hammering experiment. Then, using the dynamic simulation function of cutpro9.0, the flutter stability domain is simulated under the given radial cutting depth(cut width).The characteristics of the stability region of the main shaft speed and the axial cut depth relation are obtained.4. Optimization of cutting parameters based on geometry simulation and dynamics simulation. On the based of process system chatter stability domain simulation, cutting time as the optimization objective and cutting depth, spindle speed, each tooth feed rate as the experimental factors, orthogonal test of three factors and four levels is designed. Cutting time is obtained by geometric simulation. According to the range analysis and variance analysis, the three groups of the processing parameters were obtained. The three groups of cutting parameters were optimized further, and the optimal process parameters were determined according to the simulation results.