Regions of optimal applicability of cutting tools of superhard materials in the machining of refractory metals

The machinability characteristics of refractory metals, such as tungsten, molybdenum, tantalum, niobium, and their alloys, are examined with reference to data in the literature and experimental results. The objective is to determine the optimal applicability regions of cutters made of superhard materials (SHM). An analysis of the available data suggests that the use of SHM tools, as compared with hard-alloy tools, is efficient above a certain hardness threshold of the machined material. In particular, the use of SHM tools is recommended for tungsten and tungsten-based alloys.