Abstract
A combustion flame method enables the synthesis of diamond using acetylene-oxygen gas (C2H2/O2) combustion flame in ambient air. Recently, tungsten carbide (WC) is used as cutting tools in the machining industry. In this study, diamond films were synthesized by combustion flame on WC surfaces. However, it was difficult to synthesize the diamond films on the WC substrate surfaces. Therefore, in order to synthesize the diamond film, a two-step synthesis method was proposed. In this method, the film surface temperature and the distance of the flame inner cone from the surface for each step are changed during the synthesis. The first step was setting the film temperature to 1273 K, the second step was setting to 1223 K. The distance of the flame inner cone from the surface was changed for each step (Case 1 ;the first step: d=7.0 mm, the second step: d=7.0 mm, Case 2 ; the first step : d=7.0 mm, the second step : d=7.5 mm, Case 3 ; the first step : d=7.5 mm, the second step : d=7.0 mm). In the Case 1 and 2, the delamination-free film was synthesized on the WC surfaces, and diamonds were synthesized. However, in the Case 3, the film vvvvdelamination occurred, and good diamond films were not synthesized.
