Research On Characteristics Of Tool Wear In Laser Heating And Ultrasonic Vibration Aided Cutting Of Tungsten Carbide

Tool wear has a direct influence on machining efficiency, precision of the workpiece and stability of the machine. When the tool wear reaches a certain level, it will reduce the machining accuracy and surface quality, and it also can lead to increase of cutting force and temperature,even make the machine chatter. Therefore, the research about tool wear characteristics has a great significance to prevent premature tool and excessive wear.According to the material removal characteristics of hard and brittle material, the ultra-precision cutting method and special processing theory were combined in this thesis. By means of ultra-precision lathe and self-developed two-dimensional ultrasonic vibration device,super-hard alloy tungsten carbide was cut with PCBN tool under the combined assistance of laser heating and two-dimensional ultrasonic vibration. Under different cutting conditions, the evolution process of tool wear and its effect law on dimensional accuracy, surface quality and cutting force were clarified experimentally. Moreover, PCBN tool wear mechanism under the special thermo-mechanical coupling action was revealed through optical microscope and SEM measurement and energy spectrum analysis. Furthermore, based on time series theory, the forecast model of dimensional accuracy error for tool wear was established and verified.The research results showed that the compound cutting aided by laser heating and two-dimensional ultrasonic vibration can effectively alleviate tool wear, extend tool life, ensure dimensional accuracy, improve surface quality and reduce cutting forces. The AR model of dimensional accuracy error established in the research can predict the influence of tool wear on dimensional accuracy error with high accuracy, which laid a foundation for error compensation during precision machining.