Tribological and Grinding Properties of Spherical Diamond Grown on a Rough Discontinuous Surface

Spherical diamond particles have great potential as additive materials for improving lubricity of lubricants, and yet the complicated preparation process is difficult to meet the current industrial demand. Therefore, a novel method was proposed to deposit mass spherical diamond on the discontinuous silicon nitride (Si3N4) powder substrate by the hot filament chemical vapor deposition method. The results revealed that the substrate was covered by the spherical diamond grains with a diameter of about 20 μm. Thereafter, they were used as lubricant additives to examine the tribological and grinding properties. Therein, the Si3N4 surface had a remarkable reduction in surface roughness by a factor of 124.62% as compared to that without spherical diamond powder, while GCr15 alloy had a 31.17% increase under the same condition. Hence, our method provides a promising way to deposit the mass spherical diamond powder that might become a great abrasive material for machining the ceramic.