Study On Preparation And Properties Of TiAlN Nano-multilayer Film On Carbide

Using magnetron sputtering technology, and adjusting the process parameters: the nitrogen flow, substrate bias, sputtering power, deposition temperature and the modulation period and modulation ratio, a series of Ti Al N nano-multilayer films on cemented carbide substrate were be prepared, and X-ray diffraction(XRD), scanning electron microscope(SEM), thermogravimetric analysis, electrochemical corrosion were be used to characterize the structure and performance of Ti Al N nano-multilayer films. The influence of magnetron sputtering process on the structure and performance of nano-multilayer films were be research, the mechanism of the structure and performance of the films were be investigate.A super hardness and good abrasion resistance and high temperature resistance and corrosion resistance Ti Al N nano-multilayer film were be obtained. The main results are as follows:(1) For Ti N thin film and cemented carbide substrate and its hardness, the order of impact weight is: Rv>Rn>Rp>Rt. With the increasing of substrate bias, the film hardness increases, but adhesion strength reduced. Considering the hardness and adhesion, chose the process parameters as for preparing Ti N transition layers. The process parameters are as follows: bias is-150 V, nitrogen flow is 35 sccm, deposition temperature is 150℃, and Ti target power is 1000 W.(2) The relationship between nitrogen flow and hardness of the Ti Al N nano-multilayer film was not determined. The hardness of the film reached the maxima,which was 2900 HV when the nitrogen flow was 25 sccm. The surface topography of the films was relatively flat when nitrogen flow was 25 sccm or 35 sccm.(3) The hardness of Ti N/Al N nano-multilayer films increased first and then decreased with the bias increasing. The films showed higher hardness of 2800 HV when bias is-100 V,and shown a good surface quality.(4) There were only present Ti N and Al N phase of cubic structure in all Ti N/Al N nano-multilayer films with different modulation period. There were existed prominent correlation between modulation period and hardness of Ti N/Al N nano-multilayer films.When modulation period thickness was from 5 to 7 nm, the film showed prominent superhard property with average hardness reaching 35 GPa, However, the films did not show super-hard property among the rest of modulation period thickness, meanwhile, thefilms showed the best corrosion resistance when modulation period is 5.6 nm. The abrasion resistance and high temperature oxidation resistance of nano-multilayer film increased monotonous with the reduction of modulation period(increase of the modulation period number or the interface number), and the films showed the best wear-resisting performance when modulation period is 3.6 nm.(5) The change of the modulation ratio caused the differences of crystal structure in Ti N/Al N nano-multilayer film. When the modulation ratio is 1:35, the film just only existed Ti N and Al N phase of cubic structure, and showed superhard property(average hardness reaching 35 GPa), and showed the best wear-resisting performance and corrosion resistance property. The film showed the best high temperature oxidation resistance when modulation ratio is 1:25.(6) Considering the application of Ti N/Al N actual, the best solution design for coating on cemented carbide cutting tools was: transition layer(Ti + Ti N) + Ti N/Al N(modulation period is from 5 nm to 7 nm, modulation ratio is 1:35).