Microstructure, mechanical properties and bio-corrosion evaluation of biodegradable AZ91-FA nanocomposites for biomedical applications

• Published in: Materials science & engineering. A, Structural materials : properties, microstructure and processing Vol. 527; no. 26; pp. 6938 - 6944
• Main Authors: Razavi, M., Fathi, M.H., Meratian, M.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 15-10-2010; Elsevier
• Subjects: Applied sciences; Composites; Corrosion; Corrosion mechanisms; Corrosion prevention; Corrosion resistance; Elastic modulus; Elasticity. Plasticity; Electron microscopy; Exact sciences and technology; Magnesium alloys; Magnesium base alloys; Mechanical characterization; Mechanical properties; Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology; Metals. Metallurgy; Microstructure; Nanocomposites; Nanomaterials; Nanostructure; Nanostructured materials; Powder metallurgy; Powder metallurgy. Composite materials; Production techniques; Reinforcement; Technology; X-ray diffraction; Composites; Magnesium alloys; X-ray diffraction; Electron microscopy; Mechanical characterization; Powder metallurgy; Nanostructured materials; Elastic modulus; Body fluid; Electrochemical corrosion; Metal matrix composite; Ductility; Nanoparticle; Stress strain relation; Hardness; X ray diffraction; Compression test; Composite material; Corrosion resistance; Magnesium base alloys; Halogenapatite; Sintering; Nanocomposite; Microstructure
• ISSN: 0921-5093; 1873-4936
• DOI: 10.1016/j.msea.2010.07.063

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The presence of FA nano-particles as reinforcement in the AZ91 magnesium alloy matrix led to significant improvement in hardness and elastic modulus. The AZ91-FA nanocomposite with 20
wt.% of the FA nano-particles showed the highest yield strength, and with the increase of the FA content in the AZ91-FA nanocomposites, the ductility decreased. The AZ91-FA nanocomposites presented increased corrosion resistance compared to the AZ91 magnesium alloy and the corrosion resistance of the AZ91-FA nanocomposites increased with an increase in FA content. The AZ91-FA nanocomposite with 20
wt.% of the FA nano-particles showed optimum mechanical properties as well as the corrosion resistance.
Recently, magnesium-based materials have shown the potential to serve as biodegradable metal implant suitable for repair of load-bearing defects in osseous tissue. However, the mechanical properties of magnesium alloys were low for the load-bearing applications, and the corrosion resistance also needed to be improved furthermore. Design and preparing of a nanocomposite based on magnesium alloy might be an approach to this challenge. The aim of this work was to evaluate the effect of fluorapatite (FA) nano-particles content on microstructure, mechanical properties and bio-corrosion behavior of a nanocomposite (AZ91-FA) made of AZ91 magnesium alloy as matrix and FA nano-particles as reinforcement for load-bearing applications. Novel AZ91-FA (with 10
wt.%, 20
wt.%, and 30
wt.% of FA) nanocomposites were produced by AZ91 magnesium alloy powders and FA nano-particles using a blend-press-sinter powder metallurgy (PM) method. Microstructure, mechanical properties and bio-corrosion behavior of the prepared AZ91-FA nanocomposites, and also the AZ91 magnesium alloy as control sample, were evaluated. The results showed that the presence of the FA nano-particles in the AZ91 magnesium alloy matrix led to significant improvement in hardness and elastic modulus. The AZ91-FA nanocomposite with 20
wt.% of the FA nano-particles showed the highest yield strength, and with the increase of the FA content in the AZ91-FA nanocomposites, the ductility decreased. The AZ91-FA nanocomposites presented increased corrosion resistance compared to the AZ91 magnesium alloy and the corrosion resistance of the AZ91-FA nanocomposites increased with an increase in FA content. The AZ91-FA nanocomposite with 20
wt.% of the FA nano-particles showed optimum mechanical properties as well as the corrosion resistance.