1 grinding heat and its conduction During grinding, the disc is violently rubbed against the surface of the workpiece, so that the instantaneous temperature of the local area is more than 1000 °C. Grinding sparks is the phenomenon that the grinding debris oxidizes and burns in the air. The friction between the abrasive particles and the workpiece and the deformation energy of the metal layer are all converted into heat energy, so the grinding heat and its conduction can be expressed by the following formula Q=Q friction + Q deformation = Q workpiece + Q wear debris + Q cutting disc + Q medium 2The effect of grinding heat on processing a Causes surface burn of the workpiece: The surface of the workpiece may be burnt under the action of instantaneous high temperature. The so-called burn is generally a non-uniform annealing of the metal material on the surface of the hardened workpiece under the action of grinding heat. As a result, the surface hardness of the workpiece is reduced, thereby affecting the performance and life of the part. The surface of the workpiece with severe burns can be seen by the naked eye, and the surface presents a layer of the oxide film that is burnt yellow or black. The surface of the workpiece with a slight burn is light yellow. Grinding materials with poor thermal conductivity, such as bearing steel, heat-resistant alloy steel, etc., are the most prone to burns. Grinding Master WeChat: 2105551090 b Residual stress and crack on the surface of the workpiece: When the temperature of the grinding zone reaches a change in the metallographic structure of the metal material (referred to as phase change), the metal surface changes in the metal surface and stress is generated. When the local stress exceeds the strength limit of the workpiece material, cracks are generated on the surface of the workpiece. c Affects the machining accuracy of the workpiece: grinding heat will cause thermal expansion and deformation of the workpiece, affecting the shape accuracy and dimensional accuracy of the workpiece. (3) Measures to reduce grinding heat an According to the material of the workpiece, the aluminum flat cutting disc elements are reasonably selected to optimize the grinding performance. The hardness of the cutting disc has a large influence on the grinding heat. When the dry grinding or the workpiece is in contact with the cutting disc for a long arc length, in order to avoid burns, a soft cutting disc can be used to exert the self-sharpness of the cutting disc. In the case of particularly large amount of grinding, the atmospheric hole cutting disc can be selected, which is not easy to block, has a strong cutting force and fast heat dissipation. b, Take good cooling measures, such as using the right cutting fluid or high-pressure cooling to improve the cooling conditions. At present, for the mass-produced grinding machine, the cutting fluid temperature regulating device is used to cool the workpiece at a normal temperature. c Reasonable use of grinding amount. When the peripheral speed of the flat abrasive cutting disc is increased, the thickness of the abrasive grains of the single abrasive grains is reduced, but the number of rubbing between the cutting disc and the surface of the workpiece is increased, the grinding heat is also increased, and the surface of the workpiece is easily burned. Although the increase in the workpiece speed increases the grinding heat, it is advantageous for heat dissipation because the contact time of the workpiece in the grinding area is reduced. Therefore, the workpiece speed should be appropriately higher during rough grinding. The amount of backing knife has the greatest influence on the grinding heat. If the finely trimmed cutting disc is ground with a large backing knife, it is prone to burns.