Mg-1Zn-1Ca alloy for biomedical applications. Influence of the secondary phases on the mechanical and corrosion behaviour

JOURNAL OF ALLOYS AND COMPOUNDS

卷:831

Article

Pulido-Gonzalez, N.¹  Torres, B.¹  Garcia-Rodriguez, S.¹  Rodrigo, P.¹  Bonache, V¹  Hidalgo-Manrique, P.¹  Mohedano, M.²  Rams, J.¹ 

[1] Univ Rey Juan Carlos, Dept Matemat Aplicada Ciencia & Ingn Mat & Tecnol, ESCET, C Tulipan S-N, Madrid 28933, Spain

[2] Univ Complutense, Fac Ciencias Quim, Dept Ciencia Mat, Madrid 28040, Spain

关键词: Mg-Zn-Ca alloys;    Biomaterials;    Biodegradable implants;    Three-point bending test;    Nanoindentation;    Corrosion behaviour;   

DOI  :  10.1016/j.jallcom.2020.154735

来源: Elsevier

【 摘 要 】

An as-cast Mg-1Zn-1Ca alloy has been soundly characterized to be used as a biodegradable material in biomedical applications. Ca and Zn additions have a great influence in the microstructure, mechanical properties and corrosion behaviour of Mg alloys. SEM examinations revealed that most of the Ca and Zn atoms form Mg2Ca and Ca2Mg6Zn3 precipitates, which distribute preferentially along the grain boundaries forming a continuous network of secondary phases. The results of nanoindentation tests show differences in hardness and elastic modulus between the alpha-Mg matrix and the secondary phases. The results of three-point bending tests shows that cracks propagate following the network formed by the intermetallic compounds at the grain boundaries (GBs). The evolved hydrogen after immersion in Hank's solution of the alloy has been also estimated, showing a change in the corrosion mechanism after 160 h. The intermetallic compounds act as a barrier against corrosion, so that it progresses through the alpha-Mg matrix phase. (C) 2020 Elsevier B.V. All rights reserved.

【 授权许可】

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