Numerical investigations on the effect of ultra-high cutting speed on the cutting heat and rock-breaking performance of a single cutter

Abstract As a new drilling technology, the ultra-high-speed diamond drilling can exhibit great superiority in drilling deep hard rock, which can achieve high rates of penetration (ROP) with substantially lower energy and load. In order to better understand the removal mechanism, the effect of ultra-high cutting speed on the cutting heat and rock-breaking performance of a single cutter was investigated by using ABAQUS software. A thermal elastoplastic damage model has been established by using a finite element analysis system aiming at the linear cutting operations. The changes of stress state, strain accumulation, and heat migration in the tool unit were analyzed. The results show that when the cutting speed exceeds 8 m/s, the heat flux and mechanical specific energy (MSE) decrease as the rotary speed (RPM) increases. That is, when cutting at ultra-high linear speed (>8 m/s), more input energy was used to break rock. In addition, when the cutting speed is in the ultra-high-speed stage and continues to increase, the proportion of brittle failure of the rock will gradually increase, and a new balance will not be reached until the cutting speed reaches 12 m/s, which helps to improve the rock breaking efficiency.