Adhesion of Anodic Titanium Dioxide Coatings on Titanium Grades 5 Alloys

MARIA VERA; MARIO ROSENBERGER; CARLOS SCHVEZOV; ALICIA ARES

Orlando

Simposio; Biological Materials Science Symposium; 2015

TMS

In the present research microhardness and adhesion of thin coatings of TiO2 (40nm to 140nm) for construction of a new heart valve design are evaluated. Coatings were produced by anodic oxidation of Ti6Al4V, using H2SO4 as electrolyte at different voltages (20V to 60V), employing heat treatments of 1h at 500°C and 600°C. The Vickers ultramicrohardness of the substratecoating tribological system was measured. The adhesion of coatings was evaluated by scratch test with varying loads at rates of 2N/mm and 4N/mm up to 10N and 20N. Microhardness values increased with the temperature of heat treatments. The adhesion was dependent on the rates of increasing load. At larger rate a brittle behavior was found and the critical load decreased with heat treatment temperature. Likewise, in anodic coatings without heat treatments, of less hardness, the critical load of adherence increased with increasing the coating thickness.