Applying Nanocomposite Ni-B-ZrO2 Coating By Electroless Method on Steel CK45 and Study its Tribological Properties

Electroless nickel boron coatings usually due to wear and corrosion resistance that is well regarded. Electroless nickel boron through the chemical reduction of nickel ions on the surface of the catalytic caused and controlled until the solution is in contact with the reaction continues. In this study, Ni-B-ZrO2 nano composite coating was made by adding 4 g⁄l of ZrO2 nano particles to nickel – boron electroless solution on samples of CK45 steel; Then the coated samples heat treated for one hour at 400℃. The morphology and chemical compound was examined using SEM equipped by EDX. Electrochemical corrosion behavior of coatings in 3.5 showed by adding ZrO2nano particles the corrosion resistant of coatings improves. Electrochemical impedance spectroscopy showed that the coating after the heat treatment hadnt a protective effect And substrate are vulnerable to corrosion. Abrasion behavior by pin on disk test was measured at ambient temperature and Vickers hardness was measured by a micro hardness testing machine devices. The results showed that adding zirconia nanoparticles to the amount of 4g⁄l increased hardness and wear resistance of the coating. Coating composite samples of nickel - boron – zirconia without heat treatment the best results for the three parameters simultaneously high hardness, abrasion resistance and excellent corrosion resistance was good.