The so-called hardness of the diamond grinding wheel refers to how easy it is for the abrasive grains on the diamond grinding wheel to fall off during grinding work. We generally call it the softness and hardness of the diamond grinding wheel. Grinding wheels with different hardness are suitable for grinding different workpieces. If the diamond grinding wheel is too hard, If the blunted abrasive grains do not fall off in time, a large amount of heat will be generated and the workpiece will be burned; if the grinding wheel is too soft, the abrasive grains will fall off too quickly and cannot fully function.

1. The larger the contact surface between the diamond grinding wheel and the workpiece, the softer the diamond grinding wheel. On the contrary, choose a grinding wheel with high hardness;

2. The harder the workpiece, the softer the diamond grinding wheel you choose; the softer the workpiece, the harder the diamond grinding wheel you choose;

3. A harder grinding wheel should be selected for fine grinding and form grinding to maintain the necessary shape accuracy of the grinding wheel;

4. The hardness of the diamond grinding wheel when grinding with coolant is 1 to 2 grades higher than that of dry grinding;

5. For grinding wheels with larger particle sizes, in order to prevent the grinding wheel from being blocked by grinding debris, a softer grinding wheel should generally be selected;

6. Under the same grinding conditions, the hardness of a resin-bonded diamond grinding wheel is 1 to 2 grades higher than that of a ceramic-bonded diamond grinding wheel;

7. Compared with circumferential grinding, a softer grinding wheel should be selected for end face grinding;

8. When the rotation speed of the diamond grinding wheel is high, the hardness of the grinding wheel can be selected from 1 to 2 small grades softer.

9. When grinding workpieces with poor thermal conductivity, softer grinding wheels should be selected;

10. When grinding soft and tough non-ferrous metals, the hardness should be softer.