| With the development of science and technology, complex surface has been applied more and more widely in the field of aviation, shipbuilding, automobile, tool making, such as airfoil of airplane, body of car, blades of impeller and so on. It is necessary to find solutions to design and machine the complex surface accurately and efficiently. Numerical control electrochemical machining (NC-ECM) is a new kind of technology based on the combination of electrochemical machining (ECM) and numerical control (NC) technology. It not only has the advantage of traditional ECM, but also has the advantage of NC. The simple cathode was used in the contour evolution movement and then the problems in machining complex surface which was made of difficult-to-cut material could be solved effectively.Due to its wide adaptability and greater flexibility, the spherical cathode was used in research on the technological experiments of NC-ECM in machining complex surface which was made of difficult-to-cut material. The following work had been done:1. Some characteristics, applications and development of NC-ECM were generalized. The5-axis NC-ECM tool was also introduced.2. The shaping law of spherical cathode was analyzed based on the theory of ECM including bottom clearance, normal clearance, and side clearance under the feed motion of spherical cathode along axis and the cutting depth under the feed motion of spherical cathode vertical axis. Relations between cutting depth and working voltage, initial gap, velocity were also analyzed.3. The orthogonal experiments and the single factor experiments were finished on the NC-ECM tool. The impact of technological parameters on the experiment-result was prioritized and the influence of the technological parameters on surface roughness and cutting depth was analyzed, the optimal combination of technological parameters of the minimum value of surface roughness and the maximum cutting depth were obtained. The shaping law was verified by the basic technology experiment as well as the foundation for complex surface machining was laid.4. Based on the actual situation of NC-ECM, the reasonable tool path was designed and the3D molding, machining simulation and NC program was obtained by mastercam software. The blade surface was machined by selecting appropriate technological parameters based on experiments. |
