Synthesis of biodegradable Zn-based scaffolds using NaCl templates: Relationship between porosity, compressive properties and degradation behavior
Synthesis of biodegradable Zn-based scaffolds using NaCl templates: Relationship between porosity, compressive properties and degradation behavior
复制标题
使用 NaCl 模板合成可生物降解的锌基支架：孔隙率、压缩性能和降解行为之间的关系
DOI：
10.1016/j.matchar.2018.01.033
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发表时间：
2018-03-01
影响因子：
4.7
通讯作者：
Yuan, Guangyin
中科院分区：
文献类型：
--
作者：
Hou, Yi;Jia, Gaozhi;Yuan, Guangyin
近年来，锌基合金作为可生物降解的生物材料引起了人们的广泛兴趣。其适度的降解速率使其成为比镁基合金更好的多孔支架的潜在候选者。在这项研究中，热压烧结（HPS），以提高堆叠密度的NaCl模板。然后，通过复制NaCl模板的结构，获得具有不同孔隙率的纯Zn和Zn-3wt%Cu支架。研究了支架的孔结构、压缩性能和降解行为。具有约75%的较高孔隙率的支架显示出增强的互连性和减小的表面积，这是由于形成了更多互连的孔并且它们的尺寸增大。具有约68%的较低孔隙率的支架表现出较高的屈服强度，这是由于在变形期间较小的互连孔较早闭合。随着孔隙率的增加，腐蚀速率降低，这是由于比表面积的减小。由于Cu在Zn基体中的固溶和CuZn 5第二相的析出，加入3wt%的Cu可显著提高Zn支架的抗压性能（包括屈服强度和模量）和腐蚀速率。此外，由于加速电偶腐蚀效应，Zn-3wt%Cu支架的孔隙率对腐蚀的影响比纯Zn支架更明显。
Recently, Zn-based alloys are attracting intensive interest as biodegradable biomaterials. Their moderate degradation rate makes them a better potential candidate for porous scaffolds than Mg-based alloys. In this study, hot press sintering (HPS) was employed to enhance the stacking density of NaCl templates. And then, pure Zn and Zn-3 wt%Cu scaffolds with different porosities were achieved by replicating the architecture of NaCl templates. The pore structure, compressive properties and degradation behavior of the scaffolds were investigated. The scaffolds with a higher porosity of about 75% showed enhanced interconnectivity and reduced surface area due to the formation of more interconnected pores and the enlarged size of them. The scaffolds with a lower porosity of about 68% exhibited higher yield strength on account of the earlier closure of the smaller interconnected pores during deformation. The corrosion rate was decreased with the increase of the porosity due to the reduction of specific surface area. The compressive properties (including yield strength and modulus) and corrosion rate of the Zn scaffolds were significantly enhanced by the addition of 3 wt% Cu because of the solution of Cu in Zn matrix and the precipitation of CuZn5 secondary phase. Moreover, the effect of porosity on corrosion was more distinguishable for Zn-3 wt%Cu scaffolds than pure Zn scaffolds due to the acceleration of galvanic corrosion effect.