Effect of Stress State in Different TiN Films on Their Tribological Performances

X ray diffractometer was employed to measure the stress states of TiN films on 52100 steel substrate by ion beam enhanced deposition(IBED),plasma chemical vapor deposition(PCVD)and ion plating(IP)respectively.Analyses were carried out on the stress formation causes of the TiN films under different deposition processes.The tribological performances of the TiN films were compared at different wear conditions of load and velocity.The effect of the stress state at adjacent to the interface between TiN film and 52100 steel substrate on the adhesion strength,wear mechanisms and performances of the films was analysed.The results demonstrated that the stresses within all three kinds of the TiN films are compressive.But the microhardness of the films and film substrate adhesion decreased in the order of IBED, PCVD, IP whereas the internal stresses and the stress differences of film substrate increased in same order,which were 269.0 MPa,660.5 MPa and 1 063.3 MPa,respectively.This resulted that the former showed highest film substrate adhesion and optimum tribological performance,and the latter two showed the relatively lower film substrate adhesion and worse tribological performance.