| In today's machinery industry,chatter is a common processing phenomenon.The chatter phenomenon seriously affects the machining efficiency and quality of products.InChatter is a common processing phenomenon in manufacturing industry.The chatter phenomenon seriously affects the machining efficiency and quality of products.In recent years,the chatter has been gradually studied,and researchers try to find simple and effective methods to suppress chatter,including improving structures of processing system and adjusting cutting parameters.However,they will affect processing efficiency and increase unnecessary costs.Ultrasonic vibration assisted turning is a new type of processing technology,in this paper,ultrasonic vibration is added to turning,which is expected to suppress chatter in turning.The main research contents are as follow:(1)The mechanism of ultrasonic vibration turning is studied by displacement curve of tool.The force analysis in different stages of the tool isresearched.(2)The mechanism of regenerative chatter is studied by establishing dynamic model.The relationship between spindle speed and cutting width is analyzed by plotting the stability lobe diagram of the machining system,and the effects of different parameters on the stability lobe diagram are obtained at the same time.The effect on regenerative chatter with ultrasonic vibration is studied from the points of energy and force according to the characteristics of regenerative chatter,and the effects of different parameters on energy intake are analyzed.(3)The vibration displacement in ordinary turning is studied by the simulation system platform of MATLAB/SIMULINK.The effect of ultrasonic vibration on chatter in turning is analyzed by simulation.(4)An experimental ultrasonic vibration turning system is built.The ultrasonic vibration assisted turning experiments with large cutting depth are carried out,and the effect is analyzed by surface quality and cutting force.On this foundation,The surface quality and surface topography between ultrasonic vibration turning and ordinary turning are compared,and the chip shape and cutting force signal are contrasted based on the experiments.The suppression of regenerative chatter by ultrasonic vibration is studied by time and frequency domain analysis of cutting force signals.At the same time,the influence of different cutting parameters on the effect and the wear of cutting tools under two different machining methods are studied.(5)Finally,the experiments are carried out using 304 stainless steel,and the effect of ultrasonic vibration on chatter is further studied.The same machining result is obtained by analyzing the machined surface and the cutting force signal. |
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