Grinding wheel will appear wear and tear, the reasons for the different wear, wear the shape is not the same, today to give you about, grinding wheel shape and the reasons for what?
1) the form of wear
Grinding wheel wear wear and broken wear two forms. A represents abrasion wear, B and C represent the broken abrasive grinding wheel on behalf of the abrasive grain off.
2) the cause of wear
① wear wear wear a high degree of particles in the workpiece will wear abrasive mechanical wear, some difficult grinding material grinding, the abrasive wear phenomenon is very serious.
② oxidation of the air in the oxidation of grinding play a role. Grinding experiments carried out in vacuum found that corundum grinding wheels were much more difficult to grind low carbon steels than in air. This is due to the convection of air to reduce the grinding temperature and the oxygen in the air so that the surface of the newly generated surface of the workpiece is rapidly oxidized to form a layer of oxide film, reducing the possibility of wear of the chip, for some abrasives, the surface will be at high temperatures The occurrence of oxidation, so that the gradual consumption of this situation for the oxidation wear.
③ diffusion wear abrasive and grinding material in the grinding high temperature contact, the elements of mutual diffusion, resulting in wear and tear of the abrasive surface and wear. Two closely in contact with the metal material, at high temperature and pressure, after a certain period of time, z in its contact surface will appear diffusion phenomenon and diffusion is mutual.
④ plastic wear sub-ah grinding under high temperature, the abrasive will be deformed due to plasticity. Plastic wear depends on the hardness of the material. Grinding, the grinding contact area of the high temperature, close to the melting point of the material, if the cutting layer in the shear surface of the thermal hardness is greater than the abrasive contact area of the thermal hardness, the abrasive contact area will produce a large plastic deformation And wear.
⑤ thermal stress crushing wear
In the grinding process, the abrasive surface of the work in a few seconds to rise to 1000 ~ 2000 ℃ high temperature, but also in the grinding fluid under the cold. The frequency of this hot and cold cycle and grinding wheel speed the same. Abrasive surface in the alternating heat and force under the action of the formation of a large thermal stress, so that abrasive surface fatigue cracking or even broken. Thermal stress crushing mainly depends on the thermal conductivity of abrasive grains and the performance of grinding coolant. The smaller the thermal conductivity, the greater the temperature gradient of the abrasive grain to the inside, the greater the thermal stress, causing the abrasive grains to be cracked and cracked.