Biocorrosion and biodegradation behavior of ultralight Mg–4Li–1Ca (LC41) alloy in simulated body fluid for degradable implant applications
| Autor: | B. P. Kashyap, Talal Al-Samman, Yuri Estrin, Nityanand Prabhu, S.S. Nene |
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| Rok vydání: | 2015 |
| Předmět: |
Mg-Ca Alloys
Materials science Simulated body fluid Alloy chemistry.chemical_element Mechanical-Properties Corrosion-Resistance engineering.material Lithium hydroxide Corrosion chemistry.chemical_compound General Materials Science Composite material Microstructure Eutectic system Magnesium-Lithium Alloys Extrusion Magnesium Mechanical Engineering Metallurgy Refinement In-Vitro Degradation Vivo chemistry Mechanics of Materials Volume fraction engineering |
| Zdroj: | Journal of Materials Science. 50:3041-3050 |
| ISSN: | 1573-4803 0022-2461 |
| DOI: | 10.1007/s10853-015-8846-y |
| Popis: | Biocorrosion and biodegradation behavior of Mg–4Li–1Ca alloy were investigated for industrially important end product conditions, namely the homogenized, rolled, and rolled + annealed ones. Among the three, homogenized material showed the highest corrosion rate (27.2 mm/year) in a simulated body fluid (SBF) owing to its coarse grain structure containing long dumbbell-shaped eutectic phase. Rolled + annealed material exhibited the lowest corrosion rate (0.94 mm/year) corresponding to the highest corrosion resistance (1.854 kΩ cm2) in SBF. This higher corrosion resistance is associated with a uniform distribution of corrosion sites and a lower occurrence of twins in the microstructure. However, the rolled material showed a greater corrosion rate due to an appreciable volume fraction of {10\( \bar{1} \)1} compression twins, {10\( \bar{1} \)2} tension twins, and {10\( \bar{1} \)1}–{10\( \bar{1} \)2} double twins, which form galvanic couples with the adjacent grains that enhances localized corrosion. A mechanism of biodegradation at the alloy/SBF interface is proposed. It involves the formation of bone-like hydroxyapatite and metastable octa calcium phosphate, along with other degradation products, such as magnesium hydroxide and lithium hydroxide. |
| Databáze: | OpenAIRE |
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