Simulated Analysis And Experimental Study On Temperature Of Ultrasonic Vibration Assisted Grinding CFRP

Carbon Fiber Reinforced Plastics(CFRP)is widely used in aerospace,launch vehicle,aircraft and other high-tech fields because of its high specific strength,stiffness and modulus.In recent years,carbon fiber composite materials have been used increasingly in the global industry,and the processing demand is also increasing.Due to its anisotropy and low thermal conductivity,it is difficult to process.Especially the temperature in the grinding process affects the durability of the tool and the quality of the workpiece,and the temperature in the process is difficult to measure.Therefore,theoretical and experimental study on heat in grinding process is carried out in this paper,the main contents include:(1)Ultrasonic vibration assisted grinding of unidirectional CFRP laminates was carried out using brazed diamond tools.The grinding temperature and grinding force were measured.The empirical formulas of grinding force for each unidirectional CFRP laminates were established.The experimental results show that the grinding forces and temperatures of ultrasonic-assisted vibration grinding for 0°,45°,90° and 135° fiber oriented unidirectional CFRP laminates are different,and the grinding temperature in 0 direction is 5-52? lower than that of other fiber oriented unidirectional CFRP laminates.(2)A two-phase model for separating carbon fibers from resin was established.The distribution of temperature field in ultrasonic vibration assisted grinding of unidirectional CFRP laminates was studied.The simulation results show that the thermal conductivity of resin is smaller than that of carbon fibers because of the different material characteristics between carbon fibers and resin,which results in the temperature of resin being higher than that of carbon fibers,and the temperature field expands along the axis of carbon fibers.Based on the simulation model,the heat distribution ratio of the incoming workpiece in ultrasonic vibration-assisted grinding of one-way CFRP laminates is studied.A heat distribution ratio model of the ultrasonic vibration-assisted grinding of one-way CFRP laminates is established.It is found that the heat distribution ratio of the incoming workpiece is less than 5%.(3)Based on the linear superposition principle of mechanics,the tangential grinding force model of CFRP laminates is established,which includes the thickness of one-way CFRP laminates and the interaction of laminates.The grinding temperature of CFRP laminates is established based on the heat distribution ratio of workpiece transferred to each one-way CFRP laminates during the ultrasonic vibration-assisted grinding.Degree field simulation.The experimental results show that the accuracy of the grinding force model and temperature field simulation model of ultrasonic vibration grinding multidirectional CFRP laminates is over 80%,and the grinding force and temperature can be predicted accurately.