ANN prediction of corrosion behaviour of uncoated and biopolymers coated cp-Titanium substrates

The present study focuses on biopolymer surface modification of cp-Titanium with Chitosan, Gelatin, and Sodium Alginate. The biopolymers were spin coated onto a cp-Titanium substrate and further subjected to Electrochemical Impedance Spectroscopic (EIS) characterization. Artificial Neural Network (ANN) was developed to predict the Open Circuit Potential (OCP) values and Nyquist plot for bare and biopolymer coated cp-Titanium substrate. The experimental data obtained was utilized for ANN training. Two input parameters, i.e., substrate condition (coated or uncoated) and time period were considered to predict the OCP values. Backpropagation Levenberg-Marquardt training algorithm was utilized in order to train ANN and to fit the model. For Nyquist plot, the network was trained to predict the imaginary impedance based on real impedance as a function of immersion periods using the Back Propagation Bayesian algorithm. The biopolymer coated cp-Titanium substrate shows the enhanced corrosion resistance compared to uncoated substrates. The ANN model exhibits excellent comparison with the experimental results in both the cases indicating that the developed model is very accurate and efficiently predicts the OCP values and Nyquist plot

The effect of surface treatments on the electrochemical behavior of titanium alloy in seawater by electrochemical impedance spectroscopy (EIS)

Seawater contains many minerals, dissolved gases, including oxygen O2 cellular organisms, suspended solids and sediments that sometimes impart high turbidity. Chemical and biological characteristics of seawater make it a particularly aggressiv materials in particular titanium. Physico-chemical interactions between a metal material and its environment can lead to corrosion of material. Deterioration of metal due to microbial activity is called biocorrosion or corrosion induced by microorganisms (CIM). Because of its economic and environmental importance, CIM has been extensively over past five decades and several models studies have been proposed to explain the mechanisms biocorrosion observed. Many sectors are a facilities, plant thermal (heat exchangers). Biofilm formation on walls of conduits considerably reduces heat transfer, this is particularly important in case of heat exchanger tubes. We noted that electrode moves corrosion potential to more cathodic values. And more, the short stay of titanium in natural seawater, corrosion potential varies around - 250 mV/Ag/AgCl, and then it reaches less cathodic values to longer residence time. Electrochemical impedance measurements showed the presence of one loop relative to the capacitive charge transfer phenomenon of metal/passive layer. Keywords: Natural seawater, Titanium, OCP, Electrochemical impedance spectroscop