A comparison of wear and cutting performance between diamond composite and tungsten carbide tools

摘要

The wear coefficient of a WC cutting element was significantly higher than that for a TSDC element. In the very early stages, the wear coefficient of WC was about 140 times greater than for TSDC. With further testing the wear coefficient of WC increased very rapidly to approx 400 times greater than for TSDC after only 1500 m. This is because the thrust force and temperature of WC cutting element increased rapidly in the cutting process. Thrust force correlates closely with the wear flat area on the test elements. Thrust force is relatively small in the initial cutting stages when the wear flat area is also small; it increases as the wear flat area increases. It is observed that the rate of increase in the thrust force is different for different tool materials depending on the rate of increase in the wear flat area. The rock cutting performance of TSDC picks was much better than that of WC picks. Under the same cutting conditions, WC picks showed severe tool wear, while no obvious wear was identified on TSDC picks. The thrust force on the cutter drum laced with WC picks was significantly higher than that observed when laced with TSDC picks. The tool wear affects the cutting force in two contrasting mechanisms. As the tool wear increases, the preset depth of cut is reduced which causes the cutting force to drop. However, as the tools wear, the frictional forces increase with a corresponding increase in the cutting force. Therefore the cutting force may either increase or decrease depending on which mechanism is dominant.