Health - Biomedical implants
The French Corrosion Institute supports manufacturers of implantable medical devices in studying the mechanisms and kinetics of corrosion of their materials under simulated physiological conditions ex situ: permanent alloys (TA6V titanium, 316L stainless steel, CoCrMo) and biodegradable implants based on magnesium, zinc, iron, and polymers. Our testing covers general and localized corrosion, stress corrosion cracking, and corrosion fatigue—conducted in accordance with ASTM F2129 and ISO 10993-15, as part of European research projects.
Study of material degradation/resistance for implants
Medical implants are exposed to a complex and aggressive physiological environment: biological fluids rich in chlorides, pH variations, and cyclic mechanical stresses. Corrosion—whether general, localized, stress-related, or fatigue-induced—can compromise the mechanical integrity of the implant and lead to the release of metallic ions into surrounding tissues. These challenges apply to both permanent implants and biodegradable implants, whose degradation kinetics must be precisely characterized to meet the regulatory requirements of MDR 2017/745.
Biodegradable implants: characterization of degradation kinetics
Biodegradable implants based on magnesium, zinc, iron, and their alloys, with or without polymeric or composite coatings, gradually resorb in the body. Controlling their corrosion kinetics is critical: overly rapid degradation compromises the mechanical integrity of the implant, while overly slow degradation may delay tissue regeneration.
The French Corrosion Institute characterizes the degradation mechanisms and kinetics of these materials through electrochemical measurements and immersion tests in ex situ simulated physiological environments (PBS, Hank’s solution, artificial serum). Our analyses make it possible to identify the corrosion products formed and quantify dissolution rates—essential data for the regulatory qualification of biodegradable implants.
Stress corrosion cracking and corrosion fatigue of implants
Orthopedic, cardiovascular, and dental implants are subjected to repeated mechanical loading in a physiological environment. The combination of mechanical stresses and a corrosive medium can lead to premature failure mechanisms: stress corrosion cracking (SCC) and corrosion fatigue—two phenomena distinct from static corrosion.
The French Corrosion Institute is equipped with dedicated facilities to perform stress corrosion cracking and corrosion fatigue testing on metallic implants under ex situ simulated physiological conditions—on TA6V titanium, 316L stainless steel, CoCrMo, and biodegradable alloys.
Our missions
- Characterize mechanisms of general, localized (pitting, crevice), and galvanic corrosion of implantable materials in ex situ simulated physiological environments.
- Measure degradation kinetics of biodegradable implants (Mg, Zn, Fe, polymers) and identify the corrosion products formed.
- Develop coatings to control the corrosion kinetics of biodegradable implants and improve the resistance of permanent implants.
- Assess resistance to stress corrosion cracking (SCC) and corrosion fatigue of implantable metallic alloys.
- Provide mechanistic and kinetic data to support the regulatory approval of medical devices (MDR 2017/745).
Our services
- Electrochemical testing in simulated physiological environments: polarization curves, electrochemical impedance spectroscopy (EIS) (ASTM F2129, ISO 10993-15).
- Immersion testing and corrosion rate measurements on biodegradable implants (Mg, Zn, Fe, etc.).
- Identification and characterization of corrosion products: SEM, EDS, profilometry.
- Stress corrosion cracking (SCC) testing in ex situ physiological environments.
- Corrosion fatigue testing on metallic implants under simulated physiological conditions.
- Consulting on material selection and surface treatments for medical applications.
European projects and collaborative R&D
The French Corrosion Institute takes part in European research projects focused on corrosion and degradation of implantable materials. These collaborations enable the development of advanced testing methodologies and contribute to improving the understanding of degradation mechanisms and kinetics of implants.