The Features of CBN
March 06, 2020
The features of CBN
The hardness of CBN is higher than that of ordinary abrasive. High hardness means stronger and sharper cutting ability; CBN has high wear resistance, meaning it is more difficult to wear than ordinary abrasives; The ability to maintain the shape of abrasive grains is one of the main characteristics of CBN as a high performance abrasive. CBN has a high compressive strength, which means it can keep particles intact and not easily broken when used in harsh conditions. CBN has good thermal conductivity and can realize cold cutting in grinding.
1.High hardness and toughness
Cubic boron nitride (CBN) is the superhard material whose hardness is only second to diamond, which is much higher than ordinary corundum and silicon carbide abrasive, so it has better cutting ability and sharper.
2.High temperature resistance and good thermal stability
Cubic boron nitride can withstand temperatures of 1,250 to 1,350 degrees Celsius, more than diamond can withstand 800 degrees Celsius. When grinding and cutting iron materials, there will be no slime phenomenon, and it is the most ideal grinding wheel for metal materials sensitive to grinding temperature, such as quenched steel, high vanadium high speed steel and aluminum high speed steel.
3.Strong chemical inertness
Cubic boron nitride is not easy to produce chemical reaction with iron group elements, so it is very suitable for grinding materials with high temperature, high hardness and low thermal conductivity, such as high speed steel, tool steel, die steel, high alloy hardening steel, chromium steel, nickel alloy, powder metallurgy steel and high temperature alloy.
4.Good thermal conductivity
CBN thermal conductivity can be up to dozens of times to a hundred times of corundum grinding wheel, so can quickly export the grinding heat, reduce the thermal deformation of the workpiece. It is very suitable for grinding materials with low thermal conductivity. Various spraying (welding) materials: nickel base, iron base, etc.Wear-resistant cast iron materials: vanadium - titanium cast iron, high phosphorus cast iron, chilled cast iron, etc. Titanium alloy class: such as TC4.
5.Good grinding performance and good surface quality
Because the cubic boron nitride grinding tool can keep the sharpness of the grinding grain edge for a long time, the machining precision and surface roughness value of the processed workpiece can achieve relatively ideal results, so that the workpiece durability can be increased by 10%-30%. So even if the batch processing of the workpiece, will always get higher shape, precision and consistency. CBN grinding wheel can obtain high dimensional accuracy and low surface roughness, and the processed surface is not easy to produce cracks and burns, and the residual stress is small. Processing surface quality is improved, generally no crack, not easy to burn, and can obtain residual compressive stress, significantly improve the fatigue strength of the workpiece, the durability of the workpiece can be increased by 30-50%.
6.wear resistance, long life
The grinding ratio of CBN grinding wheel can reach 3500-5500, which is 100 times higher than ordinary corundum grinding wheel and 3-5 times higher than diamond grinding wheel.
7.Environmental protection, pollution-free, energy saving and consumption reduction
There is not much powder dust.
8.High work efficiency and good comprehensive economic benefits
Sharp grinding, small grinding force, CBN grinding wheel dressing cycle, less dressing, long replacement time;Long service cycle, high grinding ratio, better economy, good shape retention, no need to frequently replace and trim the grinding wheel, save time, improve working conditions, conducive to the processing operation.
Cubic boron nitride is not suitable for grinding hard alloy and non - metallic materials. Under high grinding temperature, chemical reaction will occur when CBN meets alkaline aqueous solution. CBN grinding wheel will decompose in alkaline solution at 300°C, which can be slightly decomposed in boiling water. As a result, the crystal shape of the grinding grains will be destroyed.