How to forge MCD，CVD diamond tools?

Single crystal diamond tools play an important role in the field of mechanical processing, widely used in the processing of ultra-precision mirror parts such as mirrors, guided gyroscopes of missiles and rockets, computer hard disk substrates, accelerator electron guns and so on. Single crystal diamond tools can also be used to manufacture ophthalmology, brain surgery scalpels, ultra-thin biological slicing knives and other medical tools.

In order to grind a high quality single crystal diamond tool, the crystal orientation technology of single crystal diamond must be mastered. This is mainly due to the anisotropy of single crystal diamond, the hardness of diamond in each direction is very different. It is necessary to choose appropriate crystal face and crystal direction as the front face and back face of the tool, that is, the blade, so that its wear resistance and machining performance can achieve the best.

Diamond crystal belongs to the cubic crystal system, with atoms are arranged on each of the crystal form and the atomic density and different distance between different crystal faces, the cause of diamond crystal anisotropy, so the diamond is not only the physical and mechanical properties of the different crystal faces ease its manufacturing, and service life are not the same, the crystal microscopic damage strength also have obvious difference. Although the grinding rate of (110) crystal is higher than that of (100) crystal,(100) crystal has higher resistance to stress corrosion and thermal degradation than other crystal surfaces considering the micro strength, using (100) surface as the front and back surface of the tool, it is easy to grind the cutting edge of high quality, and it is not easy to produce micro edge breakage.

In the good grinding direction, the grinding rate of (111) crystal surface is the lowest, followed by (100) crystal surface, and the grinding rate of (110) crystal face is the highest.

Grinding of diamond tool blanks

Diamond grinding is generally divided into coarse grinding and fine grinding, from billet grinding into a tool in the shape of a process called coarse grinding of diamond material, can use superfine particle size of diamond grinding wheel or cast iron plate on the ground, the binder, particle size and concentration of diamond has strict requirements, and in the process of grinding of grinding wheel to nap, but using the cutting fluid.

The two basic precision of single crystal diamond tools are the precision of the edge profile and the radius of the blunt circle of the edge. In order to grind high quality ultra-precision cutting tools, it is best to choose natural single crystal diamond. The cutting radius of natural diamond tools can be ground to 17= 0.1~ 0.2um, and the blade roughness can be ground to R =0.1~ 0.2um.

It is required that the roundness of the cutting edge of the arc cutter used for processing aspheric lens is less than 0.05μm, and the straightness of the cutting edge used for processing polyhedral mirror is 0.02μm. The blunt circle radius (ρ value) of the cutting edge indicates the sharpness of the cutting edge. In order to adapt to various processing requirements, the radius of the cutting edge of the cutting edge ranges from 20nm to 1μm.

Moresuperhard can provide complete cutting solutions,including turning,milling,drilling(rough /semi-finish/finish cutting),etc.We produce MCD,CVD  tools for high precision machining.

---EDITOR: Doris Hu

---POST: Doris Hu