![<?echo $_SERVER['SERVER_NAME'];?>](/template/twentyseventeen/skin/images/header.jpg)
(2) It has high thermal stability and high temperature hardness.
The heat resistance of CBN can reach 1400~1500 °C, and the hardness at 800 °C is the room temperature hardness of Al2O3/TiC composite ceramic. When the cutting temperature is high, the material to be processed is softened, and the hardness difference between the tool and the tool is increased, which is beneficial to the cutting process and has little effect on the tool life.
(3) Has good thermal conductivity.
The thermal conductivity of CBN is 1300W/(m?K), which is 3.5 times that of Zigang. The thermal conductivity of cemented carbide is only 35~75W/(m?K). The thermal conductivity of CBN material is lower than that of diamond but much higher than that of hard alloy. Moreover, the thermal conductivity of PCBN tool increases with the increase of cutting temperature, so the heat at the tip of the tool can be quickly transmitted, which is beneficial to the machining accuracy of the workpiece. Improvement.
(4) has a high Young's modulus.
The Young's modulus of PCBN is about 750 GPa, which is higher than WC, TiC, Al2O3 and other materials.
(5) Has little thermal expansion.
The thermal expansion coefficient of PCBN is about (2.1~2.3)×10-6/K, and the thermal expansion coefficient of cemented carbide is (5~7)×10-6/K.
(6) Has a small density.
The density of PCBN is 3.48 g/cm3, which is similar to the density of Al2O3 and Si3N4.
(7) Has a low fracture toughness.
The fracture toughness of PCBN is about (3.5~5) Pa?m0.5, which is only half of the ceramic tool material. This is the only shortcoming of PCBN.
(8) Excellent chemical stability.
CBN has high anti-oxidation ability. In the atmosphere, it does not produce oxidation at 1000 °C. PCBN does not decompose at 1300~1500 °C; it is not eroded in acid; it is inert to iron family materials, at 1200~1300 No chemical reaction occurs at °C. However, when it is about 1000 °C, it will hydrolyze with water, causing a lot of CBN abrasion. Therefore, dry cutting should be used when using PCBN tools.
(9) Has a lower coefficient of friction.
The friction coefficient of CBN and different materials is between 0.1 and 0.3, which is lower than the friction coefficient of cemented carbide (0.4~0.6). The friction coefficient decreases slightly with the increase of friction speed and positive pressure. It is not easy to form a retention layer or built-up edge during cutting, which is beneficial to the improvement of surface processing quality.
Previous Next
Plastic Headlight,Polishing Plastic Headlights,Car Plastic Headlight,Defog Plastic Headlights
NINGBO ZHENGUO INTELLINGENT LIGHTING CO.,LTD , https://www.zguolight.com