Microstructural, nanomechanical and wear properties of magnetic pulse electrodeposited Ni-TiN composite coatings

Abstract

The current paper reports successful syntheses of Ni-TiN composite coatings via pulse current (PC) and magnetic PC (MPC) depositions. The microstructural, nanomechanical, wear properties and wear mechanism of the Ni-TiN composite coatings were investigated via scanning electron microscopy (SEM), atomic force microscopy (AFM), transmission electron microscopy (TEM), X-ray diffraction (XRD), a nanoindenter (NI) and a high frequency reciprocating wear test instrument. The results showed that the Ni-TiN composite coating deposited at magnetic intensity of 0.3 T had numerous homogeneously dispersed TiN particles. The size of the Ni grains and the TiN particles in the coating were of nanometer size, with an average diameter of ∼ 65 nm and ∼ 25 nm, respectively. The maximum hardness and Young ' s modulus values for the Ni-TiN composite coatings, deposited at magnetic intensity of 0.3 T, were 34.85 GPa and 165.2 GPa, respectively. The wear results showed that the weight loss of the Ni-TiN composite coating was approximately 47.4 mg at a magnetic density of 0.3 T. Furthermore, the coatings deposited at 0.3 T presented low friction coefficients, with an average value of about 0.43.