Wear Resistance of Anodic Titanium Dioxide Films Produced on Ti-6Al-4V Alloy

Abstract

Ti-6Al-4V alloy with TiO 2 coating is the most commonly selected material to construct an aortic heart valve. Wear resistance is the main mechanical property to be evaluated for this purpose. In this paper, the wear resistance of TiO 2 thin films obtained by anodic oxidation of Ti-6Al-4V is evaluated. Anodic oxidation was performed at 20 V to 70 V with a H 2 SO 4 1 M electrolyte. The samples were thermally treated at 500°C for 1 h, and crystalline phases of TiO 2 were obtained. The wear was performed in a ball-on-flat reciprocating machine with a range of loads from 1 g f to 4 g f and times between 60 s and 1200 s, using a diamond sphere as counterface. The counterface oscillates at 0.5 Hz and 4 mm in amplitude. The wear is measured using a profilometer and is calculated as the worn volume. The wear resistance of the coated samples is larger than the substrate, and increases with thickness and with crystalline coating.

Szuperparamágneses vas-oxid nanorészecskék (SPIONs)teranosztikai célú fejlesztése

“…Az Erlangeni Klinikai Egyetemen Christina Janko (Prof. Christoph Alexiou, University Hospital Erlangen, Section for Experimental Oncology and Nanomedicine -SEON) áramlásos citometriával Jurkat sejt tenyészetben bizonyította, hogy a poligalláttal burkolt SPION részecskék (PGA@MNP) megõrzik az antioxidáns hatást, ami a GA esetén közismert. 34 5. Ábra He-La sejt tenyészet Berlini-kék festéssel (vas kimutatás).…”

Tribological properties of nano-graphite as an additive in mixed oil-based titanium complex grease

“…Then, a TiO 2 film was deposited on the worn steel surface, which enhanced the wear resistance of the worn surface. 23 …”

Production and Characterization of TiO2 Nanofilms for Hemocompatible and Photocatalytic Applications

“…16,30,46 In our lab, this method has been used to evaluate wear resistance using a spherical diamond ball 10 lm in radius oscillating at 30 Hz on the flat samples (bare or coated substrates) with an amplitude of 4 mm and loads ranging from 1 g f to 20 g f . 30,47,48 The wear maps obtained for the different samples tested showed that the coatings generally present a transition from mild-to-severe wear regime at a load of 5 g f for anodic coatings and of 7 g f for sol-gel coatings. 30,47,48 Also, crystalline coatings were more resistant than amorphous coatings, a fact explained by the higher hardness of the crystalline coatings.…”

“…17,30 In addition, we obtained partial crystallization of amorphous thin films by heat treatment for 1 h at 500°C and 600°C, which resulted in a mixture of anatase and rutile phases. 30,33 The best films for hemocompatible applications were obtained with heat treatment at 500°C. 30,33…”

“…30,33 The best films for hemocompatible applications were obtained with heat treatment at 500°C. 30,33…”