Improving microhardness and wear properties by surface modification on Ti-34Nb-6Sn system by plasma electrolyte oxidation.

• β Ti–Nb-Sn alloy comprise anatase, rutile, SnO and Nb 2 O 5 oxides after PEO-coating. • CP-Ti and β Ti–Nb-Sn presented basically the same thickness of the coating. • The thickness did not influence the microhardness and wear properties after PEO-coating. • After PEO-coating, the microhardness increased significantly for β Ti–Nb-Sn. • The wear volume for β Ti–Nb-Sn decrease after PEO-coating significantly compared to substrate. The plasma electrolyte oxidation (PEO) coating technique was used to fabricate a ceramic porous layer on the surface of β Ti-34Nb-6Sn alloy in a phosphate, calcium, and magnesium electrolyte (bioactive elements). The phase composition and microstructure of the substrate Ti-34Nb-6Sn (TNS) alloy was made by XRD essay and the PEO coatings were characterized by XRD and SEM analyses. The microhardness was done by Vickers microhardness and the wear assay was made by micro-abrasive wear technique. The oxide coatings can be effectively fabricated on the surface of this alloy. The pore size showed a variability and the maximum and minimum pore size values found were 2.98 µm and 0.42 µm. The PEO coatings comprised anatase and rutile TiO 2 , Nb 2 O 5 and SnO oxides. The hardness and wear properties were compared to the CP-Ti substrate. The hardness of the oxide surface coating increased significantly when compared to the metallic substrates. The wear resistance was improved after PEO-coating on CP-Ti compared to untreated material, and the treatment established the wear behavior of the TNS alloy. The improvement of the hardness, and wear resistance of the TNS alloy can be related to the oxides formed during the PEO treatment and can contribute to the development of biomedical devices advancing the biological properties when in contact with the bone tissue. [ABSTRACT FROM AUTHOR]