Fabrication and Pore Structure of Directionally Solidified Porous Mg-Zn Alloy
Fabrication and Pore Structure of Directionally Solidified Porous Mg-Zn Alloy
复制标题
定向凝固多孔镁锌合金的制备及孔结构
DOI：
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发表时间：
2021
期刊：
影响因子：
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通讯作者：
Li Zaijiu
中科院分区：
文献类型：
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作者：
Xiao Xinxiong;Liu Yuan;Jin Qinglin;Zhou Canxu;Zhang Huawei;Li Yanxiang;Li Zaijiu
采用Bridgman定向凝固法制备了藕状多孔Mg-Zn合金。研究了不同锌含量和氢压下镁合金的孔结构和孔隙率。通过理论计算预测了Mg~（-1）wt% Zn合金的气孔率。结果表明，Zn元素的加入对多孔陶瓷的孔结构有一定的影响。随着Zn含量从0wt%增加到2wt%，平均孔径增加。Mg~（-1）wt% Zn合金的孔隙率随氢压从0.1 MPa增加到0.6 MPa而明显降低。基于氢在多元金属熔体中溶解度的计算模型，对Mg~（-1）wt% Zn合金在凝固阶段（20 mm高度）氢压变化时的孔隙率进行了计算，计算结果与实验结果吻合较好。通过对显微组织的观察发现，随着Zn含量的增加，Mg-Zn合金的柱状晶向等轴晶转变。研究了Gasar镁锌合金在不同凝固阶段气孔的形成情况，为Gasar镁锌合金在生物医学领域的应用提供了理论依据。
Lotus-type porous Mg-Zn alloys were fabricated by the Bridgman-type directional solidification method. The pore structure and porosity of Mg alloys at different Zn contents and hydrogen pressures were studied. The porosity of Mg~(-1)wt% Zn alloy was predicted through the theoretical calculation. The results show that pore structure can be influenced by the addition of Zn element. As the content of Zn increases from 0wt% to 2wt%, average pore diameter increases. The porosity of Mg~(-1)wt% Zn alloy clearly decreases with increasing the hydrogen pressure from 0.1 MPa to 0.6 MPa. Based on a model for estimating the solubility of hydrogen in multi-component molten metals, the calculated results of porosity at the solidification stage (20 mm height) with a changed hydrogen pressure in Mg~(-1)wt% Zn alloy are in good agreement with the experimental results. Through observations of the microstructures, the column grains of Mg-Zn alloy change into equiaxed grains as the content of Zn increases. Also, the formation of pore at different solidification stages was studied, which can supply theoretical basis for the fabrication of Gasar Mg-Zn alloy in the biomedical applications.