The grit selection of super hard abrasives is commonly decided by the surface finishing and processing efficiency of the work pieces. The basic grit selection principles of diamond abrasive tools and CBN abrasive tools are the same. Compared with the conventional abrasives tools, to reach identical surface finishing, the super hard abrasives should be finer than 1-2 grits.
The selection of super hard abrasives and abrasive tools should take bond force of bonds. For some given bond, the removal amount of the work pieces increase among with the increase of grit. And the grinding ratio increase. However, if the grit size is large, the abrasive tools will wear faster and the grinding ratio correspondingly decrease, specially for the resin bond of weak bonding force. In return, if the grit size is too fine, the grinding force is weak, and the wheel is easy to block the working force, causing more heat, poor grinding quality and more weariness. Besides, because the blockage, the abrasive tools need to be dressed, which will cause needless non working weariness. As for the resin bond diamond super hard abrasive tools, the excessive heat on work face may cause the thermolysis of bond, increasing weariness. Consequently, as for the determination of bond type of abrasive tools, there is commonly an optimal range. Within this range, the grinding performance and weariness condition are the best. Generally, resin bond super hard abrasive tools select the grit within 100#; ceramic bond abrasive tools select the from the range 100#-180#; metal bond abrasive tools can selected from the 80#-240# range.
Different grinding steps should select the grits according to the processing condition and processing requirements and the optimum grit range.
The grit is different steps are as follow: rough grinding 80#-120#; semi-fine finishing 120#-180#; fine finishing 180#-W 40; polishing W 40-W 1.
For the specially required grinding, we recommend you to choose the finer or coarser grit. For example, in the form grinding, in order to increase the form-ability, the selection of grit should be finer than the common grinding work.