PCD performance characteristics of polycrystalline diamond tools

Diamond tool with high hardness, high  synthetic diamond  strength, thermal conductivity and good wear resistance and other characteristics, can be obtained in a high-speed cutting machining accuracy and processing efficiency. Above characteristics of diamond tools is determined by the state of the diamond crystal. In the diamond crystal, the carbon atoms of the four valence electrons enter the tetrahedral bond, each carbon atom with four adjacent atoms form a  cutting tools  bond, and then form a diamond structure, the structure is very strong binding force and direction, so that the diamond has a very high hardness. As  Abrasive grinding wheel  diamond (PCD) of varying orientation of the structure of fine grain diamond sintered body, although the added binding agent, the hardness and wear resistance is still lower than the single crystal diamond. However, due to the performance of PCD sintered isotropic and therefore not split along a single cleavage plane. PCD cutting tool materials, the main performance indicators: ① PCD hardness up to 8000HV, is 80 to 120 times carbide; ② PCD thermal conductivity of 700W/mK, as carbide 1.5 to 9 times, even higher than PCBN and copper Therefore PCD tool rapid heat transfer; ③ PCD friction coefficient is typically only 0.1 to 0.3 (carbide friction coefficient of 0.4 to 1), the PCD tool can significantly reduce the cutting force; ④ PCD coefficient of thermal expansion of only 0.9 × 10 -6 ~ 1.18 × 10 -6, equivalent to only carbide 1/5, so the PCD tool thermal deformation, high precision; ⑤ PCD cutter and non-ferrous metals and non-metallic materials, the affinity between small, in the process difficult to bond the chips formed on the tip BUE.