title collage
Photo of Ronald Wallstabe

Dr.-Ing. Ronald Wallstabe,

BAM Federal Institute for Materials Research and Testing, Working group "Failure Analysis", Berlin

Curriculum Vitae

since 06.2009 Employee at BAM Federal Institute for Materials Research and Testing Spectrum of tasks: Failure Analysis
10.2005 - 05.2009 Researcher at Institute for Materials Science II, University of Karlsruhe (TH) Collaborative Research Centre Programme 483, Subproject B2 Materials development: Surface modification of oxide ceramics Tribology: tribological characterization by laboratory tests
Teaching: - Seminars Materials Science I and II
- Basic Lab Materials Science
- Laser laboratory
04.2010 Doctorate at Karlsruhe Institute of Technology (KIT), Faculty Mechanical Engineering
"Herstellung multiphasiger Al2O3-Friktionsmaterialien und ihre tribologische Charakterisierung im ungeschmierten Gleitkontakt mit Stahl"
Degree: Doktor der Ingenieurwissenschaften
Doctoral Thesis Supervisor: K.-H. Zum Gahr
10.1999 - 07.2005 Mechanical Engineering at University of Rostock
Majors: Lightweight Design and Materials Diagnostics/Failure Analysis
Diploma Thesis: "Wear Behaviour of Coated GFRPs due to Ice"
Degree: Diplom-Ingenieur
07.2004 - 05.2005 Stay in Finland (Helsinki) employed at Helsinki University of Technology (HUT) for externally funded project "Wear of GFRPs in Ice" Study Thesis and Diploma Thesis in English

CV as pdf
His Topic of Materials' Days 2011:

Failure analysis of medical implants: importance of design, material (defects) and operational loading

Failures of medical implants often have severe consequences. For that reason the identification of possible failure causes in order to prevent future failures is crucial. In this presentation the generic conducting of failure analyses at BAM is introduced which includes the description of therefor necessary methods and actions. Moreover, a definition for medical implants is given and their special requirements are mentioned.
The results of several case studies of conducted failure analyses for a short-term implant (intramedullary hip screw) and long-term implants (hip endoprosthesis and artificial heart valve) are discussed. It was found that often a combination of several factors leads to failure of implants.
Finally, it can be concluded that the most common failure mechanisms for medical implants are fatigue fracture, corrosion and wear. The main influences on failures of medical implants are in descending order of importance: operational loading, design and material (defects).