Corrosion fatigue behavior of additively manufactured biodegradable porous iron. (1st August 2019)

• Record Type: Journal Article
• Authors: Li, Y.; Lietaert, K.; Li, W.; Zhang, X-Y.; Leeflang, M.A.; Zhou, J.; Zadpoor, A.A.
• Is Part Of: Corrosion science. Volume 156(2019)
• Page Start: 106
• Page End: 116
• Publication Date: 2019-08-01
• Subjects: Additive manufacturing -- Selective laser melting -- Iron scaffold -- Corrosion fatigue -- Biodegradation; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2019.05.003
• Languages: English
• ISSNs: 0010-938X

Abstract

Highlights: This is the first study about the corrosion fatigue behavior of selective laser melted (SLM) biodegradable porous iron based on diamond unit cells. A novel test setup was developed that complemented the fatigue test machine and ensured that cyclic loading on the specimen could occur in circulated r-SBF at 37 °C. AM porous iron exhibited high fatigue resistance with fatigue strengths being 70% and 65% of yield stress in air and revised simulated body fluid (r-SBF), respectively. How biodegradation and cyclic loading affected each other were investigated at both macro and micro scales. The observed high fatigue strength and slow biodegradation rate underline the importance of AM porous iron as a promising bone-substituting material. Abstract: The corrosion fatigue behavior of additively manufactured topologically ordered porous iron based on diamond unit cells was studied for the first time to understand its response to cyclic loading in a simulated physiological environment. The material exhibited high fatigue resistance with fatigue strengths being 70% and 65% of yield stress in air and revised simulated body fluid, respectively, mainly due to its slow degradation and excellent ductility. However, cyclic loading significantly increased biodegradation rate, especially at higher stress levels. The observed extraordinary fatigue strength, slow biodegradation and high ductility underline the importance of porous iron as a promising bone-substituting material.