Product selection of grinding wheels

Abrasive particle size
Mainly related to processing surface roughness and productivity. When rough grinding, the grinding allowance is large and the required surface roughness value is large, so coarser abrasive grains should be used. Because the abrasive grains and pores are large, the grinding depth can be larger, and the grinding wheel is less likely to get clogged and heat up. When fine grinding, the margin is small and the roughness value is required to be low, so finer abrasive grains can be selected. Generally speaking, the finer the abrasive grains, the better the grinding surface roughness.
Hardness and its selection
The hardness of the grinding wheel refers to how firmly the abrasive grains and adhesive adhere to the surface of the grinding wheel. The hardness of the grinding wheel is soft, which means that the abrasive grains of the grinding wheel are easy to fall off; the hardness of the grinding wheel is hard, which means that the abrasive grains are difficult to fall off. The hardness of the grinding wheel and the hardness of the abrasive are two different concepts. The same abrasive can be made into grinding wheels with different hardnesses, which mainly depends on the performance and quantity of the bond and the manufacturing process of the grinding wheel. The significant difference between grinding and cutting is that the grinding wheel has "self-sharpening properties". Choosing the hardness of the grinding wheel is actually choosing the self-sharpening property of the grinding wheel. It is hoped that the sharp abrasive grains will not fall off too early, nor will they become dull. fall off. The general principle for selecting the hardness of the grinding wheel is: when processing soft metals, in order to prevent the abrasive from falling off prematurely, use a hard grinding wheel. When processing hard metals, a soft grinding wheel is used in order to quickly shed the blunt abrasive grains and expose new abrasive grains with sharp edges and corners (i.e., self-sharpening). The former is because when grinding soft materials, the working abrasive grains of the grinding wheel wear very slowly, and there is no need to break away too early; the latter is because when grinding hard materials, the working abrasive grains of the grinding wheel wear faster and require faster removal. renew. When fine grinding, in order to ensure grinding accuracy and roughness, a slightly harder grinding wheel should be used. When the workpiece material has poor thermal conductivity and is prone to burns and cracks (such as grinding carbide, etc.), the grinding wheel selected should be softer.
organize
The structure of the grinding wheel refers to the proportional relationship between the volumes of the three parts of the grinding wheel: abrasive grains, binder, and pores. It is usually classified by the percentage of the grinding wheel volume occupied by the abrasive grains. The grinding wheel has three organizational states: tight, medium, and loose; it is subdivided into No. 0-14, a total of 15 levels. The smaller the tissue number, the greater the proportion of abrasive grains, and the tighter the grinding wheel; conversely, the larger the tissue number, the smaller the proportion of abrasive grains, and the looser the grinding wheel.