Benefits of coated diamonds for grinding wheels
Nowadays, diamonds coated with Ti, Ni and other metals are popularly used as abrasives in all kinds of grinding wheels. The efficiency and life of this kind of grinding wheels are several times higher than the grinding wheels with ordinary diamond abrasive.
As we know, only about 10% the diamond abrasive has the grinding effect in the grinding wheel. Most diamond grains fall off prematurely due to heat during the grinding process or due to the influence of external forces. This greatly restricts the use efficiency and life of the resin grinding wheel.
However, when the diamond surface is metalized, its overall performance will be improved to varying degrees. First of all, there will be obvious thorn-like protrusions on the diamond surface, which means that the diamond surface is roughened, which greatly improves the holding force and bonding strength of the bond to the diamond. In addition, after electroless metal plating, the compressive strength of diamond is increased by about 40% to 55%. It can greatly reduce the high load, and the probability of breaking off of diamond grains due to strong impact in the work with large cutting amount. At the same time, metals such as Ti and Ni also have good heat conduction properties, and play a good role in thermal corrosion resistance of diamond grains, which are easy to graphitize when working at high temperatures.
Of course, the metal-coated diamond abrasives also have their disadvantages. As we all know, the reason why the resin bond grinding wheel is sharper than other bond grinding wheels is that the diamond abrasive itself is continuously broken and falling off during the use. However, the metal-coated diamond is difficult to achieve the above process, because it is wrapped in Ti and Ni clothing, and the self-sharpening speed is also weaker than that of ordinary diamond abrasives. Although the service life has been improved to a large extent, its sharpness is also affected in varying degrees, and the manufacturing cost will also increase.
In fact, there is another way to go. Only adding more than 20% TI and Ni-coated diamond to the bond to replace ordinary diamond abrasives can greatly increase the life of the grinding wheel, without affecting the sharpness. Appropriate amount of coated abrasive in the bond not only played a better role than ordinary diamond abrasives, and played a certain protective effect on ordinary diamond abrasives. The coated abrasive has good bonding force, heat resistance, pressure resistance, and strong impact resistance. At the same time, it is a good support point for the nearby ordinary diamond abrasive, thereby greatly reducing the ordinary diamond abrasive due to poor holding force and collision. The chance of falling off.
Tests result showed that the resin grinding wheel produced by the above method has a life span of 1 to 1.2 times longer than that of ordinary diamond abrasive bond during use. Not only the sharpness of the grinding wheel is well guaranteed, but the increased cost is relatively small. Of course, the proportion of coated abrasives can be higher without worrying about the cost. It should be noted that during the processing, the mixture must be uniform, otherwise it will be counterproductive.