Abstract |
Magnesium alloys have been recently developed as biodegradable implant materials, yet there has been no study concerning their corrosion fatigue properties under cyclic loading. In this study the die-cast AZ91D (A for aluminum 9%, Z for zinc 1% and D for a fourth phase) and extruded WE43 (W for yttrium 4%, E for rare earth mischmetal 3%) alloys were chosen to evaluate their fatigue and corrosion fatigue behaviors in simulated body fluid (SBF). The die-cast AZ91D alloy indicated a fatigue limit of 50MPa at 10⁷ cycles in air compared to 20MPa at 10⁶ cycles tested in SBF at 37°C. A fatigue limit of 110MPa at 10⁷ cycles in air was observed for extruded WE43 alloy compared to 40MPa at 10⁷ cycles tested in SBF at 37°C. The fatigue cracks initiated from the micropores when tested in air and from corrosion pits when tested in SBF, respectively. The overload zone of the extruded WE43 alloy exhibited a ductile fracture mode with deep dimples, in comparison to a brittle fracture mode for the die-cast AZ91D. The corrosion rate of the two experimental alloys increased under cyclic loading compared to that in the static immersion test.
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Authors | X N Gu, W R Zhou, Y F Zheng, Y Cheng, S C Wei, S P Zhong, T F Xi, L J Chen |
Journal | Acta biomaterialia
(Acta Biomater)
Vol. 6
Issue 12
Pg. 4605-13
(Dec 2010)
ISSN: 1878-7568 [Electronic] England |
PMID | 20656074
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Copyright | Copyright © 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. |
Chemical References |
- Alloys
- Biocompatible Materials
- Electrolytes
- Magnesium
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Topics |
- Alloys
(chemistry)
- Biocompatible Materials
(chemistry)
- Body Fluids
(chemistry)
- Corrosion
- Electrolytes
(chemistry)
- Magnesium
(chemistry)
- Microscopy, Electron, Scanning
- Stress, Mechanical
- Surface Properties
- Temperature
- X-Ray Diffraction
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