Analysis of Wear Characteristics of Grinding Wheel

The synthetic diamond resin grinding wheel is widely used in the grinding of cemented carbide and titanium alloy due to its small grinding force and heat, good self-sharpening and high grinding efficiency. It is estimated that about 60% of the world's abrasive grade diamonds are used to make resin bonded grinding wheels. However, in the process of grinding, it is easy for synthetic diamond grit to fall off prematurely. Generally, only about 30% of the synthetic diamond grits of each grinding wheel participate in the normal grinding, many of which fall off prematurely, so this phenomenon will inevitably affect the grinding ratio of the grinding wheel.

In order to improve the grinding ratio of grinding wheel, the wear mechanism of grinding wheel must be discussed. The wear process of artificial diamond wheel in grinding process is complex, and there are many types of wear. There are mechanical, adhesive, friction, diffusion, chemical, thermal and other forms, but the main forms are as follows:

(1) The interaction between the diamond crystal surface and the material to be processed causes micro wear on the working top of the diamond grit. Sometimes, the micro graphitization of the diamond surface under the action of the grinding force would cause the grinding wheel to wear.

(2) Generally, RVD grade abrasives are used in diamond resin grinding wheel. There are pin-flake-like-shape diamond abrasives. Under the action of grinding force, crystal fracture is easy to crumble, which makes the grinding wheel wear.

(3) Due to the generation of grinding heat, the physical and mechanical properties of the bond change, which would decrease the strength of the bond and the wheel wear.

(4) Due to the poor combination of diamond abrasive and bond, the diamond abrasive would fall off prematurely under the action of grinding force.

Through the above analysis and observation of the surface morphology of resin bonded diamond wheel after grinding, it is found that there are many holes left after the diamond falls off. It is concluded that the poor combination of abrasive and binder is the main reason for the premature falling and the low grinding ratio of grinding wheel. In this paper, in order to find a way to reduce the premature falling of diamond abrasive and improve the grinding ratio of resin bonded diamond wheel, the coupling agent is taken place by wetting agent.