Study On The Rotary Ultrasonic Milling And Grinding Of Carbon Fiber Composite Technology

Carbon Fiber Composites, as a kind of advanced composites, are widely applied in aerospace, military equipments, sports apparatus, automobile manufacture fields for their excellent physical properties and mechanical characteristics. However, with the development of the performance of the carbon fiber composites, it is getting harder to machining them when using the traditional machining methods. It is difficult to ensure the workpiece's dimensional precision and surface quality, and the material would delaminate and flake, which would form dents on the surface of the workpiece.Aiming at the difficulty to machining the carbon fiber composite, a new machining method, which combined the ultrasonic machining and the traditional machining, was proposed in this paper, to seek for the effective way to improve the dimentional precision and surface quality, the specific works as follows:Firstly, an ultrasonic milling and grinding experiment plateform was built. The ultrasonic generator and amplitude transformer were designed according to the amplitude and frequency of the ultrasonic vibration. The amplitude was measured to ensure the transformer can meet the requirement of the experiment. The ultrasonic vibration system, temperature measuring system and force measuring system were installed on the machining center to complete the building of the experiment plateform.Secondly, a new evaluation criterion was established. 3D evaluating parameters Sa and Sq instead of the traditional 2D evaluating parameter Ra, were selected to serve as the evaluation criterion, which is more suitable to evaluate the carbon fiber composite.Thirdly, this paper presented the research of the lateral comparison experiment between the ultrasonic mahining and traditional machining of the non-ablating carbon fiber composite. According to the experiment report, it revealed that the ultrasonic milling and grinding were more superior than the traditonal milling and grinding.Fourthly, different ultrasonic parameters (amplitude) and machining parameters (speed, cutting depth, feed rate, step length) were chosen to machining the non-ablating carbon fiber composite, which is the longitudinal comparison test of the ultrasonic machining. The influence law of the ultrasonic parameters and machining parameters to the surface quality was revealed, and the matching relationship between ultrasonic parameters and machining parameters was obtained. Finally, based on the experimental results above, the most optimized machining parameters and most suitable ultrasonic parameters were chosen to machining the workpiece. It verified that the best surface quality and highest precision can be obtained while machininged the workpiece with the best parameters, which provided some reference significance in machining the carbon fiber composites.