SIMULATION AND EXPERIMENTAL STUDIES ON SUBSTRATE TEMPERATURE AND GAS DENSITY FIELD IN HFCVD DIAMOND FILMS GROWTH ON WC–Co DRILL TOOLS

Abstract

Uniform temperature and gas density field inside the reactor play an important role on synthesis of high-quality diamond films using hot filament chemical vapor deposition (HFCVD) method. In the present study, the finite volume method (FVM) is adopted to simulate the temperature and gas density distribution during the deposition process. Temperature–measuring experiments are conducted to verify the correctness of the simulation results. Thereafter, the deposition parameters are optimized using this model as D (filament separation) = 35 mm, H (filament–substrate distance) = -10 mm and N (number of gas inlet) = 3. Finally, experiments of depositing diamond films on WC– Co drill tools are carried out with the optimal deposition parameters. The results of the characterization by SEM and Raman spectrum exhibit that as-fabricated diamond-coated tools present a layer of high-quality diamond films with homogeneous surface and uniform thickness, further validating the accuracy of the parameter optimization using the simulation method.