Study On Drilling Temperature Field Of Unidirectional Carbon/Epoxy Composites

Carbon fiber reinforced epoxy composites(C/E composites) is concerned for its light weight, high modulus, good chemical stability, excellent specific strength and many other advantages. Its range of applications has extended from the military field of aeronautics in the past to today’s automobile manufacturing, sporting goods, electronic products and many other civilian areas. However, it is mainly concentrated more in its preparation than in the secondary processing for the C/E composites. Not much research work for the frequent C/E composites drilling processing has been done in reality, especially for cutting heat. Due to the late use of C/E composites, we have less study on the cutting heat problem. So it is necessary to commence drilling temperature of C/E composites. The main contents of the paper are divided into the following sections:(1) A drilling temperature field model of unidirectional laminate C/E composites was built by using the finite difference method. First of all, we had a unified treatment of the parameters in the equation of heat conduction. Then the three-dimensional, unsteady heat conduction partial differential equation was established in the Cartesian coordinates based on the energy conservation law and Fourier formula of the basic principles of heat and mass transfer. The drilling heat source was discussed in detail and various boundary conditions and stability conditions were studied.(2) Drilling tests under different speeds were to verify the correctness of the mathematical model of drilling temperature field. The temperature field distributions on the drilling exit plane and temperature rise curves on three different locations in the exit were measured to compare with the predicted results under3000r/min,5000r/min and7000r/min respectively. The simulation results matched well with the measured results. Homemade K-type thermocouples and FLIR infrared thermometer were used during the test.(3) The situations of different feed rates, different drilling depths, different boundary conditions and different composites materials were simulated based on the experimental verification to further enrich the temperature distributions under variety of conditions. So we could analyze the causes of the temperature field and the effects on the processing quality of the workpiece according to the results of simulation.