Prediction and optimization of electroplated Ni-based coating composition and thickness using central composite design and artificial neural network

The choice of the electroplating conditions of Ni-based alloys has always been a serious research question. In this study, an artificial neural network based on central composite design modelization were used to determine the desired percentage of Ni and the optimum thickness of the coating before passing to the implementation of the work. Three main factors were found to be very important in this process; namely applied current density (I), pH of the bath and the temperature (T) during electrolysis. The optimum conditions generated by the mathematical model proposed in this work were 42 mA cm(-2), pH 4.5 and 50 degrees C for the Ni-alloys (Zn, Co, Cr and W). Theoretically, the optimum amount of Ni and the thickness of the alloy were 40% and 23 mu m, respectively. The SEM images indicated that the optimum (I) would yield homogenous and compact morphologies. Moreover, the XPS investigations revealed that the optimum pH would form a strong Ni bond. Finally, the XRD analysis showed that the optimum T would result in a stable Ni-alloy crystallinity for Zn, Co and Cr. In contrast, Ni-W alloys showed that the amorphous phases were more stable. Graphic abstract