Characterization and Diffusion Kinetics of borided Ni–Mg Alloys

In this study, a mixture of 93% Ni–7% Mg and 97% Ni–3% Mg powders were produced by the TM method and the diffusion kinetics, surface properties of borided nickel–magnesium alloy at different temperatures and times were investigated. The samples were sintered at 530°C. The boriding process was performed Ekabor II boron powder in atmospheric furnace environment at 900, 950 and 1000°C temperatures for 1.5, 3.0 and 4.5 h. The phases in the boride layer were found by means of CuKα radiation in XRD. XRD analysis of NiB, Ni2B and Ni3B phases were obtained. The hardness of borides layer formed on surface after boriding of the 93% Ni–7% Mg and 97% Ni–3% Mg alloys substrate ranged from 1518 to 1964 HV0.05, whereas value of the unborided nickel was 112–136 HV0.05. The boron activation energy was estimated as equal to 136.506 and 158.843 kJ/mol for the borided 93% Ni–7% Mg and 97% Ni–3% Mg alloys, respectively.