As a typical representative of commonly used cemented carbide, tungsten cobalt cemented carbide (YG class cemented Carbide) refers to an alloy composed of tungsten carbide as the hard phase and cobalt metal as the bonding phase. The English name is tungsten cobalt cemented carbide, and the brand name is composed of "YG" and the average percentage of cobalt content. Such as YG6, YG8 and so on.
In terms of performance, YG cemented carbides combine the advantages of tungsten carbide and cobalt, which are mainly reflected in high hardness, good thermal conductivity, good impact toughness, high bending strength and excellent cutting resistance. However, it should be noted that different grades of YG cemented carbide physical indicators are different, such as YG6 density of 14.6~15.0g/cm3, hardness 89.5HRA, bending strength 1400MPa, impact toughness 2.6J/cm2, coercivity 9.6~12.8KA/m, compressive strength 4600MPa; The density of YG8 is 14.5~14.9g/cm3, the hardness is 89HRA, the bending strength is 1500MPa, the impact toughness is 2.5J/cm2, the coercivity is 11.2~12.8KA/m, the compressive strength is 4600MPa. In general, under certain conditions, with the increase of cobalt content, the bending strength, compressive strength and toughness of the alloy are better, but the density and hardness are lower. According to the different cobalt content, tungsten-cobalt cemented carbides can be divided into low cobalt, medium cobalt and high cobalt alloys. According to the difference of tungsten carbide grain, it can be divided into micro-grain, fine grain, medium grain and coarse grain alloy. According to the different uses, it can be divided into cutting tools, mining tools and wear tools.
From the perspective of production technology, the preparation steps of YG class cemented carbides include mixing tungsten carbide powder and cobalt powder, wet grinding, drying, granulation, pressing forming, deforming agent, sintering, etc. Note: WC powder with two kinds of coarse and fine particles is used in ingredients. The particle size of coarse WC powder is (20 ~ 30)μm, and that of fine WC powder is (1.2 ~ 1.8)μm. From the point of use, in addition to making cutting tools, drawing dies, cold stamping dies, nozzles, rollers, hammer and other wear-resistant tools and mining tools, tungsten cobalt carbide can also be used to cut cast iron, non-ferrous metals and non-metallic materials.
