Optimization on the HFCVD setup for the mass-production of diamond-coated micro-tools based on the FVM temperature simulation

Abstract

In the present study, a set of simulations is carried out to optimize the temperature field generated by a hot filament chemical vapor deposition (HFCVD) setup designed for the mass-production of diamond coated micro-tools. The finite volume method (FVM) is adopted in order to couple all three heat transfer mechanisms. The simulation results show that the filament length (L) and separation (D) largely determine the quality of generated temperature field, and their effects on the temperature uniformity are respectively along the filaments and perpendicular to the filaments. Moreover, the filament diameter (d) exhibits the largest effect on the average temperature of the generated temperature field. Based on the Taguchi simulation plan, an optimal HFCVD setup is obtained that can produce a temperature field with standard deviation (σ) and temperature range (R) as 3.57°C and 17.6°C respectively. Furthermore, a more uniform temperature field can be achieved by proposing a HFCVD setup with non-equidistant filament separations, whose σ and R further can further decrease to 1.93°C and 9.5°C respectively. Finally, the correctness of the simulation is verified by additional temperature measurements that shows that highly uniformly temperature fields can be produced by the optimized setups and the simulated results are lower than the actual temperatures by 1.65%–5.80% (for equidistant filaments) and 2.2%–5.0% (for non-equidistant filaments).