Carbide is an alloy material made from hard compounds of refractory metals and binder metals by powder metallurgy. therefore has different functions. What are the main characteristics of cemented carbide materials?
Carbide is an alloy material made from hard compounds of refractory metals and binder metals by powder metallurgy. therefore has different functions. What are the main characteristics of cemented carbide materials?
1) There is no directionality in carbide. Carbide is made from powder by pressure sintering. ducks, eliminating the local mechanical function. .
2) Carbide does not pose a heat treatment problem. In addition to the influence of thermal stress during heating and cooling, its mechanical function does not change due to heating and cooling (e.g. even after heating to 1000 °C and cooling, the mechanical function does not change ) Therefore, for the machining of this type of cemented carbide, no pre-machining can be carried out under softened bands, that is, the pre-machining of cemented carbide must be carried out before sintering and after sintering, except for the machining with diamond tools or electric machining methods In addition it cannot be machined by other simple methods The mechanical properties of cemented carbide are mainly determined by the cobalt content and the particle size of tungsten carbide.
3) Young's modulus of cemented carbide is large, Poisson's number is small, and Poisson's number of cemented carbide is 0.21 to 0.24. Therefore, under the action of machining stress changes, the size of the inner diameter of the cemented carbide mold is much smaller than that of the Steel mold so that a product very close to the mold size can be obtained.
4) Cemented carbide has high compressive strength. Compressive strength is related to cobalt content, and the low cobalt cemented carbide can reach more than 6000MPa, which is almost twice that of East-West steel. for This matériau fil used in the working part of the cold extrusion die with high unit pressure.
5) The thermal expansion coefficient of cemented carbide is small Compared with the thermal expansion coefficient of east-west steel of 11 × 10 -6 / K, the cemented carbide is 5 ~ 7 × 10 -6 / K, which should be smaller in the design and manufacture of the formulas are taken into account.
6) High thermal conductivity. The thermal conductivity of cemented carbide is three times higher than that of east and west steel. It can avoid the sintering problem between the processed material and the mold.
7) The amount of elastic deformation and plastic deformation is very small. This is an advantage for the mold, but it is an unfavorable aspect. This means that the corresponding concentration in the mold is very delicate and easily damaged, which is a major problem in the design and application of cemented carbide molds.
8) High hardness and good wear resistance This is a more popular feature of cemented carbide.
Currently, the cemented carbides used for molds in China are mainly tungsten-cobalt. in when the cobalt content is high.
Welcome to Zhuzhou Century Tool official website: zzcenturytool.cn
