Materials Science Program Seminar

THE MORK FAMILY DEPARTMENT OF CHEMICAL ENGINEERING AND MATERIALS SCIENCE PRESENTS A SEMINAR
BYSannakaisa Virtanen
University of Erlangen-Nuremberg
Dept. of Materials Sci., WWIV-LKO
Martensstr. 7, D-91058 Erlangen, GermanyElectrochemical behavior and corrosion modes of metallic materials used for biomedical applicationsAbstractThe goal of the studies is to determine critical factors in the chemical and electrochemical stability of metallic implant materials, as well as to elucidate interactions between the implant surface and the specific biological environment. The materials investigated include Ti, Ti-alloys as well as Co-Cr-Mo alloys. All these materials are generally highly corrosion-resistant. However, specific problems in the chemical and mechanical stability are being encountered with these materials, which in many cases have been attributed to the conjoint action of chemical and mechanical attack, so-called fretting corrosion. Further, clinical observations often show unexpected high accumulation of metal ions of the implant materials in tissue. The influence of various internal and external factors on passivity and its breakdown were elucidated for different implant alloys. The electrochemical behavior of the alloys was studied under simulated body conditions using conventional electrochemical techniques. For certain alloys, microelectrochemical experiments are being carried out to evaluate the local electrochemical behavior of different surface sites (i.e., different phases of two-phase alloys). Apart from metal ion release mechanisms, modification of the passive film/electrolyte-interface by specific interactions of ions present in the simulated body solution (especially Ca2+, PO43-) with the metal surfaces are being investigated by electrochemical and surface analytical techniques. In vitro metal ion release modes as well as changes in the surface characteristics are compared with results from in vivo studies. The relevance of the findings for long-term stability of implant systems will be discussed. October 21, 2005
2:45-3:30 PM
(Refreshments will be served at 2:30 PM)
VHE 217**All first year materials science majors are required to attend**

Location: Vivian Hall of Engineering (VHE) - 217

Audiences: Everyone Is Invited

Contact: Petra Pearce