Dual alloying improves the corrosion resistance of biodegradable Mg alloys prepared by selective laser melting
Dual alloying improves the corrosion resistance of biodegradable Mg alloys prepared by selective laser melting
复制标题
双合金化提高了选择性激光熔化制备的可生物降解镁合金的耐腐蚀性能
DOI：
10.1016/j.jma.2020.03.016
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发表时间：
2021-01-15
影响因子：
17.6
通讯作者：
Shuai, Cijun
中科院分区：
文献类型：
--
作者：
Gao, Chengde;Li, Sheng;Shuai, Cijun
镁合金被认为是用于可生物降解骨植入物的革命性金属生物材料，但其应用主要受到生理环境中过快降解的阻碍。本研究探讨了 Mn 和/或 Sn 对选择性激光熔化制备的镁合金性能的双重合金化效应。观察到的微观结构表明，在快速凝固过程中，含锰和/或锡合金中的晶粒和金属间相均显着细化。此外，观察到AZ61-0.4Mn-0.8Sn合金的腐蚀速率比AZ61合金降低了大约一半。腐蚀行为的改善主要是由于表面层保护作用的增强，其中富锰和/或富锡相充当了防止介质渗透的有用屏障，从而减轻了与基体的电流交换。此外，固溶Mn和/或Sn正向移动腐蚀电位，这也带来了更好的耐腐蚀性。此外，合金的强度和硬度也得到有效提高，可与皮质骨相媲美。这可能归因于溶解的Mn和/或Sn原子以及精细分散的金属间相，这可能导致晶格畸变和沉淀硬化。此外，含 Mn 和/或 Sn 的合金表现出良好的细胞相容性，如 MG-63 细胞的正常形态和增加的活力所示。这些发现表明，所开发的 AZ61-Mn-Sn 合金是可生物降解骨植入物的有希望的候选者。 (C) 2020 由 Elsevier B.V. 代表重庆大学出版。
Mg alloys have been regarded as revolutionary metallic biomaterials for biodegradable bone implants, but their applications are mainly blocked by the too rapid degradation in physiological environment. This study explores the dual alloying effects of Mn and/or Sn on the performance of Mg alloys prepared by selective laser melting. The observed microstructure indicated remarkable refinement of both the grains and intermetallic phases in the Mn- and/or Sn-containing alloys during the rapid solidification process. Moreover, approximately a half decrease in corrosion rate was observed for AZ61-0.4Mn-0.8Sn alloy with respect to AZ61 alloy. The improved corrosion behavior was primarily due to the enhanced protective effects of surface layers, in which Mn- and/or Sn-rich phases acted as a helpful barrier against medium penetration and thereby alleviated the current exchange with the matrix. In addition, the solute Mn and/or Sn positively shifted the corrosion potential, which also brought about a better corrosion resistance. Furthermore, the strength and hardness of the alloys were also effectively improved and comparable to those of cortical bone. This could be ascribed to the dissolved Mn and/or Sn atoms and the finely dispersed intermetallic phases, which might cause lattice distortion and precipitation hardening. Besides, the Mn- and/or Sn-containing alloys showed good cytocompatibility as indicated by the normal morphology and increased viability of MG-63 cells. These findings suggest that the developed AZ61-Mn-Sn alloy is a promising candidate for biodegradable bone implants. (C) 2020 Published by Elsevier B.V. on behalf of Chongqing University.