Influence of VN 2-D Inserted Layers Thickness on Microstructure and Mechanical Property of TiSiN Nanocomposite Film

Using V and TiSi targets, a series of TiSiN nanocomposite films being inserted by VN nano-layers with different thickness were prepared by RF magnetron sputtering method. Using X-ray diffraction (XRD), high resolution transmission electron microscope (HRTEM) and nano-indentation techniques, the influences of VN inserted layer thickness on microstructure and mechanical property of TiSiN nanocomposite film were investigated. The results show that, when the VN inserted layer thickness is small, the TiSiN film transforms from nanocomposite structure into nanomultilayered structure, leading to the decrease of hardness. As the VN inserted layers thicken, the hardness of film renewedly increases. When the VN inserted thickness is 0.5 nm, the film presents columnar crystals which continuously crosses through the nanomultilayers. TiSiN and VN layers exhibit coherent epitaxial growth structure, and the hardness accordingly reaches 37.2 GPa. With further increase of the VN inserted layer thickness, the coherent epitaxial growth structure is broken and the hardness of film decreases.