Helmholtz Zentrum Geesthacht, Magnesium Innovation Centre, Institute of Materials Research, Max-Planck-Str. 1, D-21502 Geesthacht, Germany.
Acta Biomater. 2013 Nov;9(10):8499-508. doi: 10.1016/j.actbio.2013.03.017. Epub 2013 Mar 20.
In previous investigations, a Mg-10Dy (wt.%) alloy with a good combination of corrosion resistance and cytocompatibility showed great potential for use as a biodegradable implant material. However, the mechanical properties of Mg-10Dy alloy are not satisfactory. In order to allow the tailoring of mechanical properties required for various medical applications, four Mg-10(Dy+Gd)-0.2Zr (wt.%) alloys were investigated with respect to microstructure, mechanical and corrosion properties. With the increase in Gd content, the number of second-phase particles increased in the as-cast alloys, and the age-hardening response increased at 200°C. The yield strength increased, while the ductility reduced, especially for peak-aged alloys with the addition of Gd. Additionally, with increasing Gd content, the corrosion rate increased in the as-cast condition owing to the galvanic effect, but all the alloys had a similar corrosion rate (~0.5 mm year(-1)) in solution-treated and aged condition.
在之前的研究中，Mg-10Dy（重量百分比）合金具有良好的耐腐蚀性和细胞相容性，具有作为可生物降解植入材料的巨大潜力。然而，Mg-10Dy 合金的力学性能并不令人满意。为了使各种医疗应用所需的机械性能得到定制，研究了四种 Mg-10（Dy+Gd）-0.2Zr（重量百分比）合金的微观结构、力学性能和腐蚀性能。随着 Gd 含量的增加，铸态合金中的第二相颗粒数量增加，在 200°C 时时效硬化响应增加。屈服强度增加，而延展性降低，特别是添加 Gd 的时效峰值合金。此外，随着 Gd 含量的增加，由于电偶效应，铸态合金的腐蚀速率增加，但所有合金在固溶处理和时效状态下的腐蚀速率相似（~0.5mm/年）。
