Abstract:Borosiliconizing of 99.9% pure nickel was performed by a powder-pack method using borosiliconizing powders at 850, 900 and 950 °C for 2 and 8 h. The coated samples were characterized by Optical Microscope (OM), X-ray diffraction (XRD) and hardness tests. The oxidation behavior of unborosiliconized and borosiliconized pure nickel was studied with the kinetics curves of cyclic oxidation. The results show that boride (Ni2B) and silicide phases (Ni3Si, Ni5Si2 and Ni2Si) are formed on the surface of borosiliconized pure nickel, which are confirmed by X-ray diffraction analysis. Depending on boronizing time and temperature, the thickness of coating layer ranges from 36 to 237 mm. The hardness of the coating layer is much higher than that of pure nickel. Dry-sliding wear tests show that the wear resistance of borosiliconized pure nickel is greater than that of pure nickel. However, the oxidation test at 950 °C indicates that unborosiliconized sample possesses higher oxidation resistance than the borosiliconized sample.