Why is the diamond grinding wheel worn?
Diamond grinding wheel is a diamond abrasive as raw materials, respectively, with metal powder, resin powder, ceramics and electroplating metal as a binder, made of the central through-hole circular consolidation abrasive called diamond grinding wheel (alloy grinding wheel), but the diamond Grinding wheel in the work will be worn, the following we come together to understand the reasons for the wear of diamond wheel:
In the workpiece material, often contains a variety of high hardness of the particles in the abrasive and the workpiece relative to the process of rubbing, the abrasive particles will be mechanical wear, so that the diamond grinding wheel is worn.
2. Oxidation wear
Common abrasives are oxides, carbides and nitrides. Oxide abrasives are stable in the air and other abrasive surfaces are oxidized at high temperatures to gradually consume.
3. Diffusion wear
Refers to the abrasive and ground material at high temperature contact, the diamond grinding wheel elements diffuse each other caused by weakening the abrasive surface caused by wear and tear. The interdiffusion of elements between the two materials is closely related to the chemical composition of the material. As the diamond abrasive in the diffusion of carbon dissolved in the ability of iron than boron nitride abrasive dissolved in the ability of iron, so the diamond grinding wheel should not be grinding steel.
4. Thermal stress damage.
During the grinding process, the working surface of the abrasive grain rises to high temperature instantaneously, and the diamond grinding wheel is quenched by the grinding fluid. The frequency of the hot and cold cycle is the same as that of the grinding wheel, so that the grinding wheel is formed on the surface of the abrasive grain. Thermal stress, so that abrasive surface cracking broken. The thermal stress is mainly determined by the thermal conductivity of the abrasive, the coefficient of linear expansion and the performance of the grinding fluid. The smaller the thermal conductivity, the greater the coefficient of linear expansion, the better the cooling performance of the grinding fluid, the greater the thermal stress, the easier the abrasive particles to heat cracking and cracking. A variety of abrasive thermal conductivity in good order, diamond, cubic boron nitride, silicon carbide, corundum.
5. Plastic wear
In the grinding under high temperature, abrasive wear due to plastic deformation. The plastic wear depends mainly on the thermal hardness of the workpiece material. Grinding, if the diamond grinding wheel on the rake face of the thermal hardness is greater than the abrasive contact area of the thermal hardness, the abrasive wear plastic wear.
The reason for the above-mentioned abrasive wear is not at the same time in every sense of cutting. According to the abrasive, the workpiece material and grinding conditions, the main reason for the wear of diamond grinding wheel will be different.