Effect of different processings on mechanical property and corrosion behavior in simulated body fluid of Mg--Zn--Y--Nd alloy for cardiovascular stent application

Abstract

The biomagnesium alloys have been considered to be one of the most potential biodegradable metal materials due to its good mechanical compatibility, biological compatibility, biological security and biodegradable characteristics. However, the two major problems of high degradation rates in physiological environment and low mechanical properties prevent the development of biomagnesium alloys. In the present work, the samples of Mg--Zn--Y--Nd alloy were prepared by cyclic extrusion compression (CEC) and equal channel angular pressing (ECAP). The microstructures, mechanical properties of alloy and its corrosion behavior in simulated body fluid (SBF) were evaluated. The results reveal that Mg--Zn--Y--Nd alloy consists of equiaxial fine grain structure with the homogeneous distribution of micrometer size and nano-sized second phase, which was caused by the dynamic recrystallization during the ECAP and CEC. The corrosion resistance of alloy was improved. The tensile and corrosion resistance were improved, especially the processed alloy exhibit uniform corrosion performances and decreased corrosion rate. This will provide theoretical ground for Mg--Zn--Y--Nd alloy as vascular stent application.

Keywords

cyclic extrusion compression / equal channel angular pressing / extrusion / magnesium alloy / corrosion

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Acknowledgements

The authors are grateful for the support by National Key Technology R&D Program of China (Grant No. 2012BAI18B01) and the National Natural Science Foundation of China (Grant No. 51171174).

RIGHTS & PERMISSIONS

2014 Higher Education Press and Springer-Verlag Berlin Heidelberg