Numerical simulation and experimental researches on different abrasive grain arrangements of monolayer diamond grinding tools fabricated by HFCVD method

Abstract

The hot filament chemical vapor deposition (HFCVD) method has been used to fabricate monolayer diamond grinding tools, whose abrasive grain arrangements can be achieved by patterned masks. The orderly arrangement pattern of abrasive grains can improve the grinding trajectory density of abrasive grains and reduce the workpiece surface roughness. In this study, the numerical simulation method is used to investigate the effect of abrasive grain pattern arrangements on the grinding trajectories and ground surface topographies, including Archimedes spiral, concentric circular, phyllotactic, disordered, and staggered patterns. The simulation results indicate that the grinding trajectory is most uniform and dense when applying the staggered pattern arrangement, and the workpiece surface roughness is lower than that of the other pattern modes. Then monolayer diamond grinding tools with five types of abrasive grain patterns are fabricated on the SiC substrate by HFCVD method. The grinding tool surface has a complete grain pattern and as-grown diamond film on the substrate is homogeneous in thickness, which is regarded as the bonding layer of the abrasive tools. EDS carbon element mapping and Raman spectra analysis reveal that the as-grown diamonds, both on substrates and seeds, exhibit high quality. Grinding experiments are performed utilizing CVD diamond grinding tools. The ground surface with a staggered pattern exhibits the lowest surface roughness without periodic grinding bands, as is consistent with the simulation results. Besides, the graphitization evaluation and worn feature statistics show that abrasive grains are of low levels of graphitization and high quantity of dynamic active grains as well as have slight abrasive grain wear and large chip space applying staggered pattern, which is the ideal abrasive grain arrangement pattern.