By hmimcu 
Diamond grinding wheels are special tools for grinding hard alloy, glass, ceramics, gemstones and other high-hard and brittle materials.
In recent years, with the rapid development of high-speed grinding and ultra-precision grinding technology, higher requirements have been placed on grinding wheels. Ceramic resin bonded grinding wheels can no longer meet production needs. Metal bonded grinding wheels have high bonding strength, good formability, and It has been widely used due to its long service life and other remarkable characteristics.
Metal bond diamond grinding wheel
Metal bond grinding wheels are mainly divided into two types: sintering and electroplating according to different manufacturing methods. In order to give full play to the role of superabrasives, foreign countries began to use high-temperature brazing technology to develop a new type of grinding wheel in the early 1990s, that is, a single-layer high-temperature brazed superabrasive grinding wheel. At present, this kind of grinding wheel in China is still in the research and development stage.
Ceramic diamond grinding wheel
Ceramic bond diamond grinding wheel has the common characteristics of diamond and ceramic bond. Compared with ordinary corundum and silicon carbide grinding wheels, it has stronger grinding force, lower temperature during grinding, and smaller grinding wheel wear; it can adapt to various coolants The role of the grinding wheel: the shape retention of the grinding wheel is good during grinding, and the accuracy of grinding the workpiece is high; the grinding wheel has more pores, which is conducive to chip removal and heat dissipation during grinding, and is not easy to block and burn the workpiece; the grinding wheel is self-sharpening It is better, the time between trimming is long and trimming is easier. Therefore, ceramic bonded diamond grinding wheels are increasingly used in some developed countries abroad.
Sintered diamond grinding wheel
Sintered metal bonded grinding wheels mostly use metals such as bronze as the bonding agent and are manufactured by high-temperature sintering methods. They have high bonding strength, good formability, high temperature resistance, good thermal conductivity and wear resistance, long service life, and can withstand large loads. Since shrinkage and deformation are inevitable during the sintering process of the grinding wheel, the grinding wheel must be shaped before use, but dressing the grinding wheel is difficult. The grinding wheel roll shaping method commonly used in current production is not only time-consuming and laborious during dressing, but also a lot of diamond particles fall off during the dressing process. The dressing wheel itself consumes a lot of money and the shaping accuracy is low.
In recent years, scholars from various countries have successively carried out research on the application of special processing methods to dress metal-bonded diamond grinding wheels, mainly electrolytic dressing methods, spark dressing methods, composite dressing methods, etc. The electrolytic trimming method is fast, but the shaping accuracy is not high; the electric spark trimming method has high shaping accuracy and can be shaped and sharpened, but the shaping speed is slow; the composite trimming method includes electrolytic spark trimming method and mechanical chemical compound trimming method. etc., the dressing effect is better, but the system is more complex, so the dressing problem of sintered diamond grinding wheels has not been well solved.
In addition, since the manufacturing process of the grinding wheel determines its random surface morphology, the geometric shape, distribution and height of the cutting edge of each abrasive grain are inconsistent. Therefore, only a few higher cutting edges cut the workpiece during grinding, which limits the grinding quality. Efficiency is further improved.
Electroplated diamond grinding wheel
Advantages of electroplated diamond grinding wheels:
①The electroplating process is simple, requires less investment, and is easy to manufacture;
②No modification required, easy to use;
③The single-layer structure determines that it can reach a very high working speed, which is now as high as 250~300m/s in foreign countries;
④Although there is only a single layer of diamond, it still has a sufficient lifespan;
⑤ For roller grinding wheels with higher precision requirements, electroplating is the only manufacturing method. Because of these advantages, electroplated grinding wheels occupy an undisputed dominant position in high-speed and ultra-high-speed grinding.
Electroplated diamond grinding wheels have defects: there is no strong chemical metallurgical bonding between the coating metal, the matrix and the abrasive. The abrasive is actually only mechanically embedded in the coating metal, so the holding force is small, and the diamond particles are heavily loaded and easy to fall off during high-efficiency grinding. (or the coating peels off in pieces), resulting in overall failure; in order to increase the holding force, the thickness of the coating must be increased. As a result, the exposed height of the abrasive grains is reduced, and the chip space is reduced. The grinding wheel is prone to clogging, the heat dissipation effect is poor, and the surface of the workpiece is prone to burns. At present, domestic electroplated grinding wheel manufacturing has not yet achieved the optimal design of the grinding wheel according to the requirements of processing conditions. The inherent disadvantages of single-layer electroplated diamond grinding wheels will inevitably greatly limit its efficient grinding application.