Comparison study of corrosion behavior for chitosan coated Ti6Al4V alloy produced by selective laser melting and forging

Abstract

In recent years, the selective laser melting (SLM) technique has attracted widespread interest due to its ability to prepare biomedical materials with complex geometries, high dimensional accuracy and cost-effectiveness. However, Ti6Al4V alloy produced by SLM technique is faced with poor corrosion resistance and bio-inertness problems. Therefore, in this study, chitosan coatings were performed on Ti6Al4V alloy produced by electrophoretic deposition (EPD) forging (traditional method) and SLM for 15 min and 30 min. Corrosion behaviors of chitosan coated surfaces were compared by using electrochemical corrosion test method in simulated body fluid (SBF). The highest corrosion potential (Ecorr) values were −504 mV for forged and −592 mV for SLM on chitosan coated surfaces for 30 min. As a result, the chitosan coating showed that the Ti6Al4V alloy produced by the SLM technique increased the corrosion resistance. When the deposition time was 30 min, the resulting chitosan coating was about 1.4 order of magnitude than the untreated sample for the Ecorr value for both sample groups. Therefore, thanks to the biocompatible chitosan coating obtained by the EPD technique, the corrosion resistance of the surfaces produced using SLM has reached a level that can compete with forged surfaces.