Study Of TiN Film Deposited By Arc Ion Plating On The Surface Of Aluminum Matrix Composites Reinforced With Carbon Fibers

Preparation of TiN films using multi arc ion plating on aluminum matrix composites reinforced with carbon fibers was studied. The four main influential factors were deposition time, target power, nitrogen flux and negative bias voltage. The optimum parameters of obtaining best composite properties were as follows: gas 350ml/min, target power 55A, deposition time 60min and bias voltage 200V.The phase structure of the TiN films was investigated by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The surface microstructures of TiN were observed by scanning electron microscope (SEM) and atomic force microscopy (AFM). The hardness and modulus of TiN film was measured by nanoindentation, and adhesion force of films by scratching test. The electrochemical corrosion behaviors of the TiN films in 3.5% NaCl solution were investigated by potentiostat.The investigations reveal that the technical parameters of multi arc ion-plating have remarkable effect on the surface quality and roughness of TiN films. The roughness decreases with increase of negative bias voltage and deposition time decreasing. Negative bias voltage and deposition time have obviously influence on the nanoindentation hardness and elastic modulus of the TiN films. The corrosion resistant property of aluminum matrix composites coated with TiN is greatly improved, which means corrosion current reducing and corrosion potential increasing. There are two main mechanisms of the corrosion of the coated composites. The dot corrosion occurs with the thin and porosity coatings with pin-liked defects obtained under low negative bias voltage and short deposition time, and the uniform corrosion does with the thick coating formed under high negative bias voltage and long deposition time.