Tailoring Ti Grade 2 and TNTZ alloy surfaces in a two-step mechanical–chemical modification

The aim of this work was to improve the surface properties of cp-Ti Grade 2 and β-Ti alloy TNTZ (Ti-29Nb-13Ta-4.6Zr) for biomedical applications. A hybrid surface treatment consisting of shot peening and chemical etching was conducted. Subsequently, the physicochemical properties and topography of the modified surfaces were analysed. Microhardness measurements of the shot-peened samples revealed a great increase in the surface hardness to the similar level as can be achieved for the ultrafine-grained and nanostructured materials. Roughness tests and microscopic observations showed significant topographical differences, depending on the material and modification process involved. Moreover, in this paper we demonstrate the influence of the substrate and treatments on the wettability. Obtained results confirmed that designed hybrid modification of Ti Grade 2 and TNTZ has significant potential for biomedical applications.