Growth Study Of Diamond Single Crystal Tool Blanks By MPCVD

Single crystal diamond cutting tools are key tools in the field of modern high-precision machining,possessing high hardness,thermal stability,and chemical inertness.They can be used in high-speed cutting,grinding,and polishing processes,and are widely applied in high-precision machining fields such as automotive parts,aerospace components,and electronic devices.With the booming development of these industries,single crystal diamond cutting tools have a vast market,and the current production capacity of natural diamond cutting tools is far from meeting daily production needs.Due to the high production cost of natural diamond cutting tools,the production of single crystal diamond tool blanks through the artificial growth of diamonds has become urgent.The MPCVD method can achieve high-quality,large-scale production of diamond single crystal tool blanks.Compared with other diamond growth technologies,MPCVD has the advantages of low defect density,good single crystal performance,and lower production costs.The use of high-purity reaction gas during the chemical vapor deposition process for growing single crystal diamond can reduce impurity contamination,resulting in higher purity of diamond crystals.In order to achieve large-scale production of diamond single crystal tool blanks,this experiment plans to simulate and optimize the existing MPCVD equipment in order to obtain a larger plasma-excited electric field and increase the effective growth area of diamond,thereby improving the equipment’s growth efficiency.In this paper,the electromagnetic field distribution was simulated and designed using finite element electromagnetic simulation software to optimize the structure of the cylindrical chamber,increasing the effective growth diameter of diamond from 54 mm to 60 mm,effectively improving the effective growth area of diamond and the growth efficiency of the equipment.The dimensions of the reaction chamber were processed based on the simulation data,and an automatic control program for the equipment was developed to produce and assemble an unmanned MPCVD device.Through the cylindrical chamber MPCVD equipment,using a 6 k W,2150 MHz microwave source imported from Germany,the optimal growth temperature and growth conditions for methane and nitrogen were explored,resulting in the production of high-quality and high-performance single crystal diamond tool blanks.