Micro-scratch and corrosion behavior of functionally graded HA-TiO2 nanostructured composite coatings fabricated by electrophoretic deposition

Farnoush H., Aghazadeh Mohandesi J., Çimenoğlu H.

Journal of the Mechanical Behavior of Biomedical Materials, cilt.46, ss.31-40, 2015 (SCI-Expanded) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 46
  • Basım Tarihi: 2015
  • Doi Numarası: 10.1016/j.jmbbm.2015.02.021
  • Dergi Adı: Journal of the Mechanical Behavior of Biomedical Materials
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.31-40
  • Anahtar Kelimeler: Functionally graded material, Micro-scratch, Electrophoretic deposition, Hydroxyapatite, Corrosion behavior
  • İstanbul Teknik Üniversitesi Adresli: Evet

Özet

In the present study, functionally graded coatings of HA/TiO2 nanoparticles and HA-TiO2 nanocomposite coatings with 0, 10 and 20wt% of TiO2 were fabricated by electrophoretic deposition on Ti-6Al-4V substrate. The functionally graded structure of HA/TiO2 coatings was formed by gradual addition of HA suspension into the deposition cell containing TiO2 nanoparticles. Micro-scratch test results showed the highest critical distances of crack initiation and delamination, normal load before failure and critical contact pressures for functionally graded coating. It was observed that the improvement of adhesion strength and fracture toughness of functionally graded coatings would be due to the reduction of thermal expansion coefficient mismatch between Ti-6Al-4V substrate and HA. The results of potentiodynamic polarization measurements showed that the graded structure of the coating could efficiently increase the corrosion resistance of substrate.