Precision grinding refers to the selection of fine grain grinding wheel on the precision grinding machine, and through the fine dressing of grinding wheel, so that the grinding grain has micro edge and isometric property. After grinding, the grinding marks left by the grinding surface are extremely fine and the residual height is extremely small.

The general principle for selecting hard grinding wheel is as follows:

(1) When the grinding tooth surface is in discontinuous state, a hard grinding wheel should be selected.

(2) In order to maintain better grinding accuracy, hard grinding wheel was selected. When carburizing and hardening gears are grinding, the grinding wheel with medium hardness is selected.

Bonding agent: bonding agent is the abrasive material bonded together. The strength, impact resistance and heat resistance of grinding wheel mainly depend on the type and nature of bonding agent of grinding wheel.

For carburized and hardened gear grinding, the vitrified diamond grinding wheel should be selected.

Ceramic knife, Ceramic knife) is started using a new type of kitchen utensils and appliances in recent years, high purity superfine zirconia powder is used as raw material, under the condition of the high temperature of one thousand degrees, the spray granulation, isostatic pressing molding, precision machining and other process manufacturing, and has high hardness, strong corrosion resistance, good chemical stability, high wear resistance, high toughness and other characteristics, Beautiful and exquisite in appearance, with sharp edge, it is a real knife that never wears and never corrodes. The sharpness of the blade is more than ten times that of the steel knife. This kind of knife is the product of modern science and technology, and has the superiority that the metal knife can't match before.

Due to the influence of the performance of engineering ceramics, there are the following characteristics in the grinding process:

(1) The grinding wheel wear is large and the grinding ratio is small. The removal mechanism of engineering ceramics is brittle failure, which is different from that of grinding metals. Metal materials are removed by plastic deformation to produce continuous chips. Engineering ceramics are removed by brittle cracking and producing fine powdery chips. The pulverized chips can easily remove the bond from the grinding wheel, causing the diamond particles to fall off and speeding up the grinding wheel wear. The greater the fracture toughness of the grinding ceramic material, the greater the grinding force and the more serious the grinding wheel wear. This not only results in lower grinding efficiency, but also a smaller grinding ratio. The grinding ratio of ceramic grinding with diamond wheel is 1/30 of that of glass grinding.

(2) The grinding force is large and the grinding efficiency is low. When grinding ceramic materials, the ratio of tangential grinding force Fc to radial grinding force Ep is much smaller than that of steel (Fc/FP-0.3 ~ 0.5), generally Fc/Fp <0.1. Because the hardness of ceramic material is very high (HVl500 ~ 2800), the radial grinding force Fp when grinding it is large, acting on the grinding wheel
The force on the shaft is large, and the elastic deformation of the shaft increases accordingly, which is easy to produce vibration and affect the grinding of the workpiece surface
Quality, reduce grinding effect.

CBN grinding wheel is suitable for high-speed, ultra-high-speed grinding, and grinding sharp, small unit wear, grinding steel wear ratio can reach 4000-10000, equivalent to the ordinary high-speed grinding wheel 150-200 times, so the grinding efficiency is very high.

CBN grinding wheel has such advantages that it can not only improve the finishing level of key parts, but also improve product quality and production efficiency.

At present, the pillar industry of powder metallurgy is automobile industry. As powder metallurgy technology is a kind of material saving, energy saving, less investment, no pollution of metal forming process, has long received the attention of the automotive industry, Ford, GM, Toyota, Honda and so on have opened the powder metallurgy business divisions.