3D honeycomb nanostructure-encapsulated magnesium alloys with superior corrosion resistance and mechanical properties. (1st April 2019)

• Record Type: Journal Article
• Authors: Shuai, Cijun; Wang, Bing; Yang, Youwen; Peng, Shuping; Gao, Chengde
• Is Part Of: Composites. Number 162(2019)
• Page Start: 611
• Page End: 620
• Publication Date: 2019-04-01
• Subjects: Honeycomb nanostructure -- Encapsulation -- Mg alloys -- Corrosion resistance; Composite materials -- Periodicals; Materials science -- Periodicals; Composite materials; Periodicals; Electronic journals; 620.118
• DOI: 10.1016/j.compositesb.2019.01.031
• Languages: English
• ISSNs: 1359-8368

Abstract

Abstract: Magnesium (Mg) alloys are promising biodegradable metals for biomedical applications but limited by their too fast degradation rates. In this study, selective laser melting was used to fabricate three-dimensional honeycomb nanostructure-encapsulated Mg alloys, in which the honeycomb nanostructure was constructed by graphene oxide (GO) as a second phase and the grains of Mg alloys were encapsulated in the honeycomb unit. Results showed that GO distributed along the grain boundaries and gradually wrapped ɑ-Mg grains as GO content increasing. It was worth noting that a honeycomb nanostructure was formed with ɑ-Mg grains encapsulated in the honeycomb unit at a certain GO content (1.0 wt% in this study). As a result, the corrosion resistance and mechanical properties were both improved, which might be ascribed to the following mechanisms: (I) ɑ-Mg grains were refined due to the reduced connection and promoted nucleation by GO; (II) Benefiting from the outstanding anti-permeability of GO, the honeycomb nanostructure acted as a tight barrier to restrain the propagation of corrosion; (III) GO reinforced the corrosion layer to prevent it falling off the Mg matrix; (Ⅳ) The oxygen-containing groups on GO facilitated the deposition of bone-like apatite and further hindered the invasion of corrosive medium. These findings demonstrated the multiple defensive roles against corrosion in the honeycomb nanostructure-encapsulated Mg alloys and their great potential in biomedical applications.