Abstract: Parts with rapid change of local geometric feature are usually critical parts in high-end equipments, which are difficult or inefficient to process on account of the adoption of difficult-to-machine material and special structure. In this way, it cannot satisfy the rapid development of high-end equipments. As the development of NC process technology, the high efficiency NC machining technology for the parts with rapid change of local geometric feature becomes a popular and difficulty issue in the industrial field. Employing the constant machining parameter to process the parts with rapid change of local geometric feature wholly is less applicative because of the existence of rapid change of local geometric feature, which restricts the machining efficiency improvement of such parts. Aiming at the parts with rapid change of local geometric feature, the quick partition method based on the rapid change of local geometric feature for the CAD model of complex surface and the mathematical modeling of machining error based on the dynamic characteristics of machine tool for the functional structure are studied. A sub-regional process method with variable parameters for the parts with rapid change of local geometric feature is proposed. The serialized processing program is generated based on the continuous characteristics of machining region, and the parts with rapid change of local geometric feature can be processed precisely and efficiently with NC equipment. The research achievement provides a new machining process for the parts with rapid change of local geometric feature.

Key words: dynamic characteristics, local geometric feature, precision machining, surface partition, variable parameter