Diamond grinding wheel is a special tool for grinding hard and brittle materials such as cemented carbide, glass, ceramics and gemstones. In recent years, with the rapid development of high-speed grinding and ultra-precision grinding technology, higher requirements are put forward for grinding wheels. Ceramic resin bonded grinding wheel can no longer meet the production needs, and metal bonded grinding wheel has been widely used for its remarkable characteristics such as high bonding strength, good formability and long service life. Metal bonded diamond grinding wheels can be divided into sintering and electroplating according to different manufacturing methods. In order to give full play to the role of superhard abrasive, a new type of grinding wheel, namely, high-temperature brazed single-layer superhard abrasive wheel, has been developed abroad since the early 1990s. 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 same characteristics as diamond and ceramic bond. Compared with ordinary corundum and silicon carbide grinding wheels, the grinding force is stronger, the grinding temperature is lower and the grinding wheel wear is smaller. Can adapt to the role of various cooling fluids; When grinding, the grinding wheel has good shape retention and high grinding accuracy; There are many air holes in the grinding wheel, which is beneficial to chip removal and heat dissipation during grinding and is not easy to block and burn the workpiece; The grinding wheel has good self-sharpening, long dressing interval and easy dressing. Therefore, some developed countries abroad are increasingly using ceramic bonded diamond grinding wheels.
Sintered diamond grinding wheel
Sintered metal bond grinding wheels are mostly made of bronze and other metals by high temperature sintering. They have high bonding strength, good formability, high temperature resistance, good thermal conductivity and wear resistance, long service life and can bear large loads. Due to the inevitable shrinkage and deformation in the sintering process of grinding wheel, it is necessary to reshape the grinding wheel before use, but it is difficult to dress the grinding wheel. At present, the commonly used grinding wheel double-roll dressing method is not only time-consuming and laborious to dress, but also the diamond particles fall off more during dressing, which consumes a lot of dressing wheel itself and has low dressing accuracy.
In recent years, scholars all over the world have successively carried out research work on dressing metal-bonded diamond grinding wheels by special machining methods, mainly including electrolytic dressing and EDM dressing. Electrolytic dressing method is fast, but the shaping accuracy is not high; EDM dressing method has high precision and can be used for shaping and grinding, but the shaping speed is slow. Composite dressing methods include electrolytic EDM composite dressing method, mechanochemical composite dressing method and so on. The dressing effect is good, but the system is complex, and the dressing problem of sintered diamond grinding wheel has not been well solved.
In addition, because the manufacturing process of grinding wheel determines that its surface morphology is random, the geometric shape, distribution and cutting edge height of each abrasive particle are inconsistent, and only a few higher cutting edges cut the workpiece during grinding, which limits the further improvement of grinding quality and grinding efficiency.