Simulation And Verification Of NC EDM Trajectory For Two-stage Shrouded Integral Turbine Blisk

Turbine blisk is the core component of aerospace engine,and its performance will directly determine the performance of aerospace engine.Turbine blisk structure tends to be integral,shrouded and multi-stage structure,which greatly improves the comprehensive performance of turbine blisk.Multi-axis NC EDM has become the mainstream trend due to the large degree of bending and twisting of blades and narrow passage of blades.The simulation and verification of the machining trajectory of the formed electrodes are of great significance in NC EDM due to the complexity of the forming electrodes and the machining trajectory.Based on the compressed voxel model method,the simulation and validation of EDM trajectory for two-stage shrouded integral turbine blisk are studied in this paper.In order to improve the efficiency of simulation,the compressed voxel model method is introduced,and the Boolean operation criterion of the compressed voxel model is obtained by analyzing its internal data structure.The traditional Marching Cube algorithm is optimized and a new surface extraction algorithm of the compressed voxel model is obtained.Based on the method of compressed voxel model,a local two-channel voxel model of two-stage shrouded integral turbine blisk and a compacted voxel model of forming electrodes are generated,which reduces the storage capacity of the model.A swept voxel model of forming electrodes is constructed according to the trajectory of EDM,and the multi-axis NC EDM trajectory simulation is completed by Boolean subtraction of voxel with the local two-channel blank compressed voxel model;the optimized Marching Cube algorithm is used to extract the surface of the model after simulation processing,and the local two-channel simulation processing surface model is obtained.A FABS error analysis method is proposed,which is used to analyze the error of the main profile in the local two-channel simulation processing.In this paper,the simulation and validation of the machining trajectory of a two-stage shrouded integral turbine blisk is completed by developing the five-coordinate numerical control EDM simulation and validation system,which guarantees the correctness of the design of forming electrode and path planning.