Fundamental Research On Preparation Of CBN Coated Tool Based On Micro/Nano Diamond Film Interlayer

Cubic boron nitride is a super-hard material that is only less than diamond. It has excellentchemical properties, especially no chemical reaction with ferrous materials. As a cutting tool coating,cBN can cut ferrous materials which diamond coated tools can’t. Therefore, cBN tool coating has avast appliation foreground in cutting tool coating. In order to explore a processing technique of cuttingtool coating, fundamental research on preparation of cBN coated tool based on Micro/Nano diamondfilm interlayer was studied in this paper. The main work and results obtained in this paper are asfollow:1. Four kinds of cBN growth model and its theoretical fault were discussed. The principles of cBNdeposition by radio frequency magnetron sputtering were analyzed, which provide guidance leading toimprovement deposition apparatus and heating equipment and negative substrate bias.2. Micro/Nano diamond film interlayer was deposited using the preliminary optimized technologyparameters in HFCVD system, with excellent surface quality and adhesion performance. The grain sizeof the diamond film was20to50nm, and its roughness average Ra was22.6nm.3. The influence of cBN coating was investigated under different ion bombardment angle andenergy by computer simulating studies. The reasonable angle of the substrate bias was perpendicular tothe DC electric field, and the bias should not be too large. The number of Ar-ions and N-ions increasedwith ion bombardment energy.4. CBN coating was deposited on Micro/Nano diamond film interlayer by RF magnetronsputtering deposition method. The influence of various factors, such as substrate bias voltage andtemperature, working gas pressure, etc, on the preparation of cBN had been studied systematically. Thesuitable parameters of the deposition of cBN were as follows: the substrate bias-150V, the gas pressure0.6Pa, the volume ratio of N2and Ar1:9. Its performance had been tested to the extent that cBN toolcoating had excellent adhesion performance based on Micro/Nano diamond film interlayer.