Temperature field simulation and optimization of processing parameters for laser-assisted machining of 3Y-TZP ceramics

Abstract

To obtain low surface roughness in the laser-assisted machining of 3Y-TZP ceramics, a laser-assisted heating model of 3Y-TZP ceramics was established. The temperature field in the cutting zone was simulated using ABAQUS software to analyze the effects of laser power, rotational speed, and warm-up time on softening layer depth (distance between the workpiece surface and lower boundary of softening layer) and thickness (distance between the upper and lower boundaries of softening layer). Furthermore, the accuracy of the simulation results was verified through experiments. The Plackett-Burman design, Steepest ascent experiment, and Box-Behnken design method were used sequentially to optimize process parameters, and the surface quality, chip morphology, and tool wear of 3Y-TZP ceramic with laser-assisted cutting and traditional cutting were compared under the best process parameters. The results show that the rotational speed and laser power are the main factors influencing the softening layer depth and thickness, and the suitable warm-up time is 15 s; the most influential factor on the surface roughness is the cutting depth, and the optimized process parameter combinations for the best surface roughness are as follows: laser power of 90.3 W, rotational speed of 400 r/min, cutting depth of 0.21 mm, and feed speed of 4.4 mm/min; with laser-assisted, the surface roughness value of the workpiece is reduced by 54.12 %, the amount of tool wear is reduced by 56.5 %, the chip morphology is transformed from powder to strip with a length of more than 50 μm, and the primary material removal mode is changed from brittle removal to plastic removal.