A cubic boron nitride (CBN) grinding wheel characteristics
Cubic boron nitride (CBN) is a human synthesis of superhard material hardness only to diamond. Compared with ordinary matter or with the diamond abrasive than has its unique properties, these characteristics can be summed up five characteristics:
1, high temperature resistance, good thermal stability. Cubic boron nitride can withstand high temperature of 1250-1350 ° C, the heat resistance than diamond 800 degrees even higher. And when grinding appear cremation, can still maintain good grinding performance.
2, chemical inertness. Cubic boron nitride and iron group elements is not easy to produce a chemical reaction, so for a variety of high-speed steel, tool steel, high alloy hardened steel, chromium steel, nickel alloys, powder metallurgy steel and high temperature alloys such as high temperature, high hardness, thermal conductivity low material is very suitable for grinding.
3, the grinding performance. As CBN abrasive grains can be maintained long-term micro-edge sharpness, will make the workpiece machining accuracy and surface roughness values are achieved more satisfactory results, thus allowing the workpiece durability increased by 10% -30% . Therefore, even if the batch processing of the workpiece, will always get a high shape accuracy and consistency.
4, high efficiency and dressing the grinding cycle. CBN grinding wheel normal speed can reach 45m/s-60m/s, even to the higher line speeds (150m / s). Moreover, in the course of a long cycle trimming, trimming minimal amount, especially suitable for automatic production line for high-precision machining.
5, the economy and long life. As CBN wheel with high processing efficiency, less wear, surface quality, easy to control scale precision, less auxiliary working hours, low waste, etc., so the overall cost is very low, with good economic benefits.
The sum up, compared with the ordinary abrasive, hardness, cubic boron nitride is much higher, the thermal conductivity, thermal expansion coefficient and excellent polishing ability is much higher, the grinding is a very excellent material. In addition, the stability of cubic boron nitride and chemical inertness is also much better than the diamond, so difficult for ordinary abrasive machining and processing of diamond and should not be regarded as a iron group metals are very suitable abrasive, especially suitable for processing high-speed steel, tool steel , tool steel, bearing steel, stainless steel, nickel, cobalt based alloys, chilled cast iron and other ferrous metals.
Notably, CBN should not be hard grinding carbide and nonmetal materials. In the grinding temperatures, CBN case of alkaline aqueous chemical reaction occurs, the result will reflect the crystal grains was destroyed, so when grinding only use the coolant oil, and not water-based coolant.
Second, cubic boron nitride (CBN) grinding wheel classification
Produced with CBN abrasive CBN grinding wheel is. Depending on the process and the different components of the binding agent used can be divided into the following four. Their properties and mechanical processing are different.
1, electroplated CBN grinding wheel
Simple molding is a major feature of this wheel, but only one layer of coating, can not be trimmed, and in the process, is difficult to know when the grinding layer is damaged. It is suitable for small batch machining and forming complex geometry and grinding wheel used as a correction.
2, sintered CBN grinding wheel
Due to the high hardness and density characteristics suitable for processing into a high-precision dressing roller, but the cost is high. Mainly used wheel dressing roller and processing large quantities of superhard materials.
3, resin bond CBN wheels
CBN grinding wheel molding resin is relatively simple, but not easy to trim. Mainly used for multi-shape small batch processing, so grinding tools and tooling industries wider use.
4, vitrified bond CBN wheels
Vitrified bond CBN grinding wheel with strong force, can achieve high-speed processing and does not burn the workpiece, combined with easy to trim, durability, etc., you can call it is the most ideal for high speed, high efficiency and high precision grinding tool. Primarily for automatic grinding machine processing ......
