Study of Ti@Ti-38Zr-11Nb layered composite material with magnetron titanium coating for medical applications

Medical implants must be highly biocompatible, exhibit the required strength, and possess a low elastic modulus similar to that of bone tissue. The challenge faced in this regard is increasing the implant surface resistance to bacterial colonization while maintaining favorable conditions for cell adhesion and proliferation. The aim of this study was to investigate a layered composite material based on a Ti-38Zr-11Nb β-titanium alloy with a magnetron-deposited titanium coating intended for use in loaded medical implants. The Ti-38Zr-11Nb alloy was produced by argon-arc remelting, followed by thermomechanical treatment and quenching. Surface modification was achieved by magnetron sputtering of titanium in an argon atmosphere. The morphology, phase composition, surface topography, coating adhesion strength, and mechanical and biological properties of the material were assessed. It was established that a dense nanostructured titanium coating approximately 600 nm thick with developed micro- and nanotopography forms on the alloy surface. The adhesive strength of the coating is 520 ± 130 mN, indicating reliable adhesion of the layers. The alloy is characterized by a reduced elastic modulus (95 – 97 GPa) while maintaining high strength properties. Furthermore, coating application has virtually no effect on the elastic modulus and nanohardness of the material and is accompanied by a moderate decrease in ductility. In vitro studies on HSF human fibroblast cultures demonstrated the absence of cytotoxicity and high cell viability (over 90%). The obtained results can be used to create medical implants with reduced rigidity and a functionally modified surface using the Ti@Ti-38Zr-11Nb composite material.