Electrophoretic deposition of zirconia-Bioglass composite coatings for biomedical implants.
Composite bilayer coatings on Ti6Al4V substrates were prepared by electrophoretic deposition, a simple and fast low temperature coating technique. Biocompatible yttrium-stabilized zirconia (YSZ) in the form of nanoparticles and bioactive Bioglass (45S5) in the form of microparticles were chosen as coating materials. The first layer consisted of 5 microm of YSZ, deposited with the intention to avoid any metal tissue contact. The second layer consisted of 15-microm thick 45S5-YSZ composite, supposed to react with the surrounding bone tissue and to enhance implant fixation. The adsorption of YSZ nanoparticles on 45S5 microparticles in organic suspension was found to invert the surface charge of the 45S5 particles from negative to positive. This enabled cathodic electrophoretic deposition of 45S5, avoiding uncontrolled anodization (oxidation) of the substrate. The coatings were sintered at 900 degrees C for 2 h under argon flow. The characterization was performed using SEM, EDX, and nanoindentation (cross section). Potential applications in the orthopedics field are discussed.
Radice
S
S
Swiss Federal Institute for Materials Testing and Research EMPA, Feuerwerkerstrasse 39, CH-3602 Thun, Switzerland. simona.radice@empa.ch
Kern
P
P
Bürki
G
G
Michler
J
J
Textor
M
M
D000497:Alloys; D001696:Biomechanical Phenomena; D002516:Ceramics / Q000737:chemistry; D020099:Coated Materials, Biocompatible / Q000737:chemistry; D004586:Electrophoresis; D005898:Glass; D006358:Hot Temperature; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D053758:Nanoparticles / Q000737:chemistry / Q000648:ultrastructure; D019736:Prostheses and Implants; D014025:Titanium / Q000737:chemistry; D015019:Yttrium; D015040:Zirconium / Q000737:chemistry
D000497:Alloys; D020099:Coated Materials, Biocompatible; C425330:bioactive glass 45S5; C031462:titanium alloy (TiAl6V4); D015019:Yttrium; D015040:Zirconium; D014025:Titanium; C028541:zirconium oxide