J. Mater. Sci. Technol. ›› 2016, Vol. 32 ›› Issue (9): 874-882.DOI: 10.1016/j.jmst.2016.07.004

Special Issue: 2016腐蚀与防护专辑

• Orginal Article • Previous Articles     Next Articles

Microstructure, Mechanical Properties, Corrosion Behavior and Biocompatibility of As-Extruded Biodegradable Mg-3Sn-1Zn-0.5Mn Alloy

Hou Lida1,Li Zhen1,2,Zhao Hong3,Pan Yu1,Pavlinich Sergey1,Liu Xiwei1,Li Xinlin1,Zheng Yufeng1,4,Li Li1,2,*()   

  1. 1 Center for Biomedical Materials and Engineering, Harbin Engineering University, Harbin 150001, China
    2 Institute of Materials Processing and Intelligent Manufacturing, Harbin Engineering University, Harbin 150001, China
    3 Hospital of Heilongjiang Province, Harbin 150001, China
    4 Department of Materials Science and Engineering, College of Engineering, Peking University, Beijing 100871, China
  • Received:2016-03-21 Accepted:2016-05-24 Online:2016-09-20 Published:2016-11-02
  • Contact: Li Li

Abstract:

The microstructure evolution and mechanical properties of biodegradable Mg-3Sn-1Zn-0.5Mn alloys were investigated by the optical microscopy, X-ray diffractometer and a universal material testing machine. The corrosion and degradation behaviors were studied by potentiodynamic polarization method and immersion test in a simulated body fluid (SBF). It was found that the as-extruded Mg-3Sn-1Zn-0.5Mn alloy has the fine equiaxed grains which underwent complete dynamic recrystallization during the hot extrusion process, with the second phase particles of Mg2Sn precipitated on the grain boundaries and inside the grains. The tensile strength and elongation of as-extruded Mg-3Sn-1Zn-0.5Mn alloys were 244?±?3.7?MPa and 19.3%?±?1.7%, respectively. The potentiodynamic polarization curves in SBF solution indicated the better corrosion resistance of the as-extruded Mg-3Sn-1Zn-0.5Mn alloy in the SBF solution. Immersion test in the SBF solution for 720?h revealed that the corrosion rate of as-extruded Mg-3Sn-1Zn-0.5Mn alloy was nearly 4?±?0.33?mm/year. The hemolysis rate of as-extruded Mg-3Sn-1Zn-0.5Mn alloy was lower than the safe value of 5% according to ISO 10993-4. As-extruded Mg-3Sn-1Zn-0.5Mn alloy showed good biocompatibility after being implanted into the dorsal muscle and the femoral shaft of the rabbit, and no abnormalities were found after short-term implantation. It was revealed that the as-extruded Mg-3Sn-1Zn-0.5Mn alloy is a promising material for biodegradable implants, which possesses an interesting combination of preferred mechanical properties, better corrosion resistance and biocompatibility.

Key words: Biodegradable magnesium alloy, Extrusion, Mechanical property, Corrosion, Biocompatibility