Analysis of Wear Mechanisms in PCD Grinding with Vitrified Bonded Diamond Grinding Wheels Based on a Friction Model

 

The market for diamond-containing cutting materials such as polycrystalline diamond (PCD) has been undergoing strong growth for years. A large part of the industrially available PCD consists of randomly distributed, intergrown diamond crystals, between which a small proportion of a residual cobalt catalyst is present. Due to its hardness, this two-phase material is often machined by grinding. Long machining times and high grinding wheel wear are characteristics of this process.

Oil is most commonly used as a cooling lubricant in the grinding of polycrystalline diamonds. Although it is known that the grinding wheel wear and the achievable process productivity depend on the properties of the cooling lubricant, it has not yet been sufficiently researched which cause-effect relationships exist between the physical properties of the cooling lubricant and the process condition and result variables when grinding PCD with water-based cooling lubricants and how these can be explained. Through an enhanced understanding of the process, there is an opportunity for economic optimization of the grinding process of polycrystalline diamonds.

The overall objective of this project is therefore to predict the thermal and mechanical loads during the grinding of a polycrystalline diamond as a function of the physical properties of the cooling lubricant and the grinding parameters, and to explain the resulting grinding wheel wear and cutting mechanisms.