Study On (Ti, Nb) N Hard Coating Synthesized By Reactive Magnetron Sputtering

The purpose of this project is to deposit a hard coating in the razor-blade to enhance the sharpness and comfort of the blade and to study the processing parameters and performance of the film. In this article, the development of hard coating has been summarized; especially TiN multi-coating and nano hard coating. In the base of these, dual target magnetron sputtering method has been applied to deposit (Ti,Nb)N hard coating in the razor surface and blade. The phase structures and properties of the samples obtained by different temperature and air pressure of the coating have been discussed.Experimental equipment has been modified to satisfy the project needs, which includes increasing double target co-sputtering system as well as workpiece support. Using small plane sputtering source as the basic model and gradually approaching the reality model, we derive revolving substrate and ring sputtering source two theoretical models separately and ultimately derive the theoretical model which is in line with the practical conditions, then make a dimensionless operation to the ultimate theoretical model and obtain the optimum target-substrate distance by making the theoretical calculations using Matlab. The calculation method and procedures can also be applied to other double target sputtering system design, as long as the corresponding parameters can be changed.In order to study the temperature influence on film surface morphology and phase structure, adjusting the reactive temperature in 300℃-500℃scope. The results show that the grain size decreases and the film grain becomes more uniform and compact with the increase of the air pressure. The Gibbs free energy of different compounds in the deposition system has been calculated according to the thermodynamics theory, and the temperature and properties of the coatings are discussed. At relatively low temperature (300℃), the TiN phase is in possession of the priority formation, while Nb can not combine with N, only can replace part position of Ti in the TiN lattice to form a replacement solution phase. When the temperature increases to 400℃, ions can achieve enough energy to overcome the NbN barrier. At this time, not only TiN phase but also NbN phase has been formatted.In order to study the air pressure influence on the phase structure and rigidity of the (Ti,Nb)N film, making a series of experiments changing air pressure to 0.2pa,0.3pa,0.4pa,0.6pa,0.8pa and l.Opa under 400℃. The results indicate that the (Ti,Nb)N film grow along (111) phase mainly when the air pressure is below 0.4pa; while the (Ti,Nb)N film grow along (200) phase mainly when the air pressure is upper than 0.4pa. Furthermore, the matrix hardness of the film and substrate increases at first and then decreases when the (Ti,Nb)N film grow along (200) phase mainly. The maximum hardness is 194HV and appears at 0.8pa air pressure.In order to study the sharpness of the razor blade edge, making cutting force test and SEM scanning to the blade edge, the results show that sharpness and hardness is proportional in the circumstances of the intact blade edge. It plays a vital role that the width of the blade edge and the blade angle in the cutting force test. To achieve the sharpness of Gillette blade, the first and foremost thing is to improve the grinding process to reduce the width of the blade edge and the blade angle.