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Failure Analysis

In addition to the failure analysis performed during laboratory evaluation of new alloys for stress corrosion cracking and corrosion fatigue, a large portion of our work is related to failure analysis of retrieved implants. Approximately 20 years ago, we began by setting up our own implant retrieval program to evaluate all implants removed from patients regardless of condition. Since that time we have continued to evaluate failed implants from a variety of sources outside the University Medical Center. Analysis is usually composed of compositional analysis, light microscopic examination including optical metallography where applicable, hardness evaluation, and scanning electron microscopy. Where available, this information is correlated with clinical record data. Results of these studies have allowed us to correlate information such as fracture surface morphology of retrievals with our basic research on the stress corrosion cracking and corrosion fatigue of the different implant materials. Because of the information that we have gleaned over the years, research in our own laboratories as well as the results of research by others, has become more easy to interpret and has led us to a greater understanding of the effects of materials processing on properties.