Elevated temperature behaviour of Ti6Al4V sheets with thermo-electro-chemical modified surfaces for biomedical applications

Abstract

Deformation at elevated temperature of Ti6Al4V sheets may represent a process route alternative to machining and Additive Manufacturing (AM) operations to produce biomedical implants characterized by a high surface-to-thickness-ratio. The paper investigates the mechanical and microstructural behaviour at elevated temperature of Ti6Al4V sheets whose surface was properly modified through thermo-electro-chemical processes to enhance the roughness, and therefore osseointegration, as well as bioactivity, to meet the requirements imposed by the specific biomedical application. After the surface characterization, tensile tests were carried out at different temperatures on samples modified on the surface in order to investigate the ductility, microstructure and micro-hardness after deformation and the effect of the surface treatments on them. The optimal surface treatment and deformation temperature were identified, which assured, at the same time, significant ductility increase compared to room temperature, and preservation of the roughness and bioactivity characteristics.

Keywords

Titanium sheet surface modification high temperature behaviour biomedical

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