Corrosion and antibacterial performance of novel selective-laser-melted (SLMed) Ti-xCu biomedical alloys

Abstract

Ti-xCu biomedical alloys were designed to have satisfactory antibacterial properties compared to pure Ti. Ti-xCu (x = 0, 3, 5, 7, and 10 wt%) alloys were prepared by selective laser melting (SLM) using powders of pure Ti and pure Cu. Increasing Cu content decreased the grain size, increased the amount and size of Ti2Cu particles, and increased the hardness. The electrochemical experiments revealed that Ti-5Cu had the best corrosion resistance, and excessive Cu decreased the corrosion resistance. In vitro culture of MG63 cells showed that SLMed Ti-xCu had good cytocompatibility. In vitro antibacterial test of E. coli showed that SLMed Ti-3Cu presented a stable highly-effective antibacterial rate (antibacterial rate>99%), in which the Cu content of 3 wt% was lower than the minimum copper content requirement of 5 wt% in conventional-processes manufactured Ti-Cu alloys that presented a stable highly-effective antibacterial rate. The mechanisms of corrosion and antibacterial performance were clarified. The SLMed Ti-xCu with antibacterial ability is a promising biomedical implant material. The content of the Cu was recommended to be 3~5 wt%.