1) Cutting disc size From the geometrical considerations, the finer the particle size of the cutting disc, the smaller the surface roughness value of the grinding. However, when the abrasive grains are too fine, the cutting disc is easily blocked by the wear debris. If the heat conduction is not good, the burned surface may be generated on the machined surface, and the surface roughness value is increased. Therefore, the particle size of the cutting disk is often taken as 46 to 60.
2) The hardness of the cutting disc The 5 inch resin cutting disc for metal is too hard, the abrasive grains are not easy to fall off, and the blunt abrasive grains cannot be replaced by new abrasive grains in time so that the surface roughness value is increased. The cutting disc is too soft, the abrasive particles are easy to fall off, the grinding effect is weakened, and the surface roughness value is also increased. Medium soft cutting discs are often used.
3) Cutting disc structure The proportion of abrasive grains in the compact structure is large, and the pores are small, and a small surface roughness value can be obtained in the case of forming grinding and precision grinding. The loose cutting disc is not easy to block, suitable for grinding soft metal, non-metallic soft materials and heat sensitive materials (magnet steel, stainless steel, heat-resistant steel, etc.), and can obtain a small surface roughness value. In general, medium-sized cutting discs should be used.
4) Cutting disc material The cutting disc material is properly selected to obtain a satisfactory surface roughness. Oxide (corundum) cutting discs are suitable for grinding steel parts; carbide (silicon carbide, boron carbide) cutting discs are suitable for grinding cast iron, hard alloys, etc.; high hard abrasives (synthetic diamond, cubic boron nitride) Cutting disc grinding can obtain very small surface roughness values, but the processing cost is high.
5) Cutting disc trimming Cutting disc trimming also has an important influence on surface roughness. Finely trimmed cutting discs are effective in reducing the surface roughness of the workpiece being ground.
In addition, the nature of the workpiece material, the choice of cooling lubricant, etc. also have a significant impact on the surface roughness of the grinding.