Revestimento de zircônia sobre liga de titânio para aplicações biomédicas

Abstract

The growing demand for safer and more effective biomaterials accompanies the advancement of medicine, and surface properties play a significant role in these applications. In this way, surface modifications enable the development of more advanced materials, and the deposition of thin films offers highly attractive benefits for biomedical applications. In this work, a yttria-stabilized zirconia film, with a thickness of 470 nm, was deposited on titanium discs, using the electron beam deposition technique. The microhardness and Young's modulus of both the substrate and the film were evaluated using the instrumented microhardness test, using a Berkovich tip, and the Vickers hardness was estimated using mathematical relationships. The microabrasive wear coefficient was determined through a rotating ball test, using Calotest equipment adapted with a load cell. The wettability of the film was evaluated using the contact angle test, in accordance with ASTM D7334-08. The results demonstrated an increase in the microhardness of the material in relation to the substrate, although, under high load (2,000 mN) small cracks were formed in the film. There was a 44% increase in resistance to microabrasive wear and the contact angle results suggest that the material has the potential to promote greater osteointegration, increasing its bioactivity at the interface with the natural tissue. Based on the improvements observed in the evaluated properties, it is concluded that the electron beam deposition technique is suitable for the application of yttria-stabilized zirconia thin films in biomaterials. [resumo fornecido pelo autor]