Study On Vibration Characteristics Of Complex Surface Die Steel At High Speed Milling

Complex surface die is one of the most important equipments. It has a direct impact on the upgrading of products and plays a significant role in the modern manufacturing industry. The capacity of producing large precision moulds is a comprehensive reflection of the national manufacturing level and has great economic and social benefits. The phenomenon of vibration is an inextricable part of any machining processes. Cutting vibrations can reduce the shape surface precision,tool life and productivity of working. This paper mainly focuse on vibration analysis in complex surface mould. Basing on the cutting mechanism, a comprehensively systematic research including theoretical and experimental analysis was made to the high speed cutting of the milling force and vibration analysis in cutting process.1.Many parameters should be concerned in the process of complex surface machining, which interact with each other. The cutting force is an important parameter, it is the basis of reseaching"tool-workpiece"system, creating model and analyzing dynamics.Based on the milling force model, the cutting force coefficients were identificated by experiments. The experimental and simulation results demonstrate the milling force and the accuracy of the milling force coefficients. Moreover, the effects of the spindle speed, feed per tooth and depth of cut on the cutting force coefficients are also investigated.2. Considering the complexity of the milling process, tool vibration is the main factor of the influences for surface quality. The FEM software-ANSYS was used to analyze the vibration modal of the actual structure of cutting tool and workpiece in the process of milling complex surface. Then the analysis results were compared with the results of experimental modal. Compared the natural frequencies measured by the experimental modals and the finite element modals analyzed of modal vibration mode, they are uniform, which prepared for the research of milling vibration characteristics.3. Considering the complexity of the structure and the force in HSM system, the experiments, including the blank of spindle and high-speed machining, are designed and carried out to investigate the vibration of the spindle and workpiece thoroughly. Then, changing laws of the vibration of spindle and workpiece under different cutting conditions for NAK80 steel were quantificationally described and systematically analyzed through a series of single factor experiments. Moreover, the internal reasons caused by cutting vibration are also discussed. These results indicate a foundation not only for taking effective measures to reduce cutting vibration and improve the quality of the machined surface, but also for researching, detecting and analyzing cutting vibration and revealing the mechanism of vibration.