The Effect Of N Content On The Microstructure And Hardness Of TiN,ZrN,CrN,TiCrN And TiZrN Films

At present,it has taken a great deal of research on TiN,ZrN,CrN,TiZrN and TiCrN films,but the knowledge and experience about the optimal contral of N content are limited.It is helpful to get the best range of N content in different films by studying on the influences of N content on the microstructure and hardness of TiN,ZrN,CrN,TiCrN and TiZrN films.The TiN,ZrN,CrN,TiCrN and TiZrN films was prepared using multi arc ion plating in this experiment.And the microstructure and hardness were analyzed by scanning electron microscopy?SEM?,energy dispersive spectrometer?EDS?,X-ray diffraction?XRD?and Vickers hardness tester.The influences of N content on the phase structure and hardness of TiN,ZrN,CrN,TiCrN and TiZrN filmsare investigated under the condition that the nitrogen contents of the films deviate from stoichiometric ratio.It is found that the TiN films are all composed of a single phase of TiN with N/Ti atomic ratio from 0.6 to 1.2.And the TiN and ZrN films tend to grow preferentially along?111?crystallographic plane and the lattice constants become a little larger with the increase of nitrogen content in the films.The phase compositions of chromium nitride films are transform from Cr₂N to Cr₂N+CrN and to CrN with increasing nitrogen content in the films,and corresponding to 38.8%,50.61%and 54.16%N content respectively.The peak hardness value of chromium nitride films occurs at the nitrogen content of about 50%in the films.The TiZrN and TiCrN films are all composed of a single face centered cubic phase without TiN,ZrN or CrN separate phase although the nitrogen content changes in a wide range.The TiZrN films exhibit a single preferred plane?111?while the TiCrN films exhibit dual preferential orientations,?111?and?200?planes.The peak values in hardness of the TiN,ZrN,CrN,TiCrN and TiZrN films appear at the nitrogen content close to the 50%.