INFLUENCE OF HEAT AND CHEMICAL-THERMAL TREATMENT OF DIAMOND TYPE Ib SINGLE CRYSTALS ON STATIC STRENGTH

Abstract

The growing requirements for the performance of drilling tools require the development of methods of obtaining diamonds with high and stable strength indicators, which depend on the efficiency and speed of drilling operations. Scientific research in this area has shown that the efficiency of the drilling process largely depends on the strength and hardness of diamond single crystals, which work under a load close to the critical one. This can lead to the complete destruction of crystals without the step-by-step chipping typical for the drilling process with the possibility of forming new cutting edges. The results of an experimental study of the effect of chemical-thermal treatment and annealing at 1150 °C on the value of the static strength of large crystals of diamonds of type Ib of octahedral habit, obtained by the method of HTNR crystallization, were obtained. It has been experimentally confirmed that an increase in the value of the critical load leads to a decrease in the particles formed as a result of destruction. The maximum value of static strength that was obtained was 8750 N. It was established that to ensure a sufficient surface of the cutting part of the drilling tool, it is advisable to use single crystals up to 1-1.6 mm in size.