Estimation of the effect of process parameters of plasma nitriding on the surface hardness and corrosion behaviour of pure titanium by artificial neuron network

In this study, Artificial Neuron Network (ANN) was used to determine the effect of the process parameters of plasma nitriding on the surface microhardness. Process parameters include temperature, time, atmosphere, applied voltage, and pressure. The temperature has the highest effect; thus, validation was carried out by sequent experiments. It was shown that the plasma nitrided sample at 600oC had a higher microhardness value, equaling 593 HV0.25, almost twice that of pure titanium. Moreover, to investigate the corrosion properties of samples and the relationship between the surface parameters and corrosion resistance, polarization (PDS) and Electrochemical Impedance Spectroscopy (EIS) were performed. Finally, the sample treated at 600oC has better corrosion resistance which equals 99.515 ohms. It is shown that the corrosion resistance is positively related to the ratio of surface roughness to the maximum height of peaks.