24TH INTERNATIONAL SYMPOSIUM ON
METASTABLE, AMORPHOUS AND
NANOSTRUCTURED MATERIALS (ISMANAM 2017) 18TH-23RD
JUNE, 2017 PALACIO MIRAMAR, SAN SEBASTIÁN – DONOSTIA (GUIPÚZCOA),
SPAIN
ABSTRACTS BOOK
1
NM-15P Plasma Electrolytic Oxide Coatings on AZ31 Mg Alloy Reinforced with Carbon Nanotubes by the Sandwich Technique
C. A. Isaza M.1, B. Zuluaga D.1, H. A. Estupiñan Duran1, J. M. Herrera Ramirez2, J. M. Meza1
1Universidad Nacional de Colombia, Facultad de Minas, Departamento de Materiales y Minerales, Cl 75 No. 79A 51, 050032, Colombia
2Centro de Investigacion en Materiales Avanzados (CIMAV), Laboratorio Nacional de Nanotecnologia, Miguel de Cervantes 120, 31136, Chihuahua, Chih., Mexico Email: [email protected]
Magnesium matrix composites reinforced with carbon nanotubes (CNTs) are candidate materials for aerospace, defense and biomedical applications owing to their low density and good mechanical and physical properties. In the case of biomedical applications, especially for hard-tissue applications, it is foreseen the application of functional coatings or films in order to ensure that the materials are biocompatible.
In this study, AZ31 magnesium alloy reinforced with multi-walled carbon nanotubes (MWCNTs) was synthesized by the sandwich technique [1], which produces materials comprised of a metallic matrix and banded structured-layers of MWCNTs. Then the composites were coated by plasma electrolytic oxidation (PEO) using a solution of potassium hydroxide (KOH) and sodium metasilicate pentahydrate (Na2SiO3·5H2O). Figure 1 shows one of the composites coated. Finally, the samples were exposed to corrosion tests by electrochemical impedance spectroscopy (EIS).
The mechanical properties (hardness, elastic modulus and adherence) of the coating were characterized by nanoindentation and scratch tests. The phases, morphology and composition in the interface were characterized by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). The results show good mechanical properties of the PEO coating and very good corrosion resistance of the composite.
Fig. 1. Cross-section micrographs of the PEO coating in the AZ31 alloy reinforced with 1.0 wt% of MWCNTs.
1. Isaza, C., G. Sierra, and J. Meza, Journal of Manufacturing Science and Engineering 138, 024501 (2016).
10 – 15 µm
AZ31/MWCNTs
PEO
Interface
Resine
NANOSTRUCTURED MATERIALS ISMANAM 2017, SAN SEBASTIÁN, SPAIN
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