金属-气体共晶定向凝固工艺参数对藕状多孔金属镁结构的影响

Effect of Gasar Processing Parameters on Structure of Lotus-type Porous Magnesium

利用自行开发的Gasar装置,成功制备了具有规则气孔分布的藕状多孔金属Mg,并研究了铸型预热温度和气体压力等工艺参数对气孔率、气孔大小和分布的影响。结果表明:提高铸型的预热温度可以完全消除铸锭侧向的无气孔金属壳;随着氢气压力的增大,铸锭的气孔率和气孔平均直径都在减小、气孔的尺寸分布均匀性提高。

Directional solidification of metal-gas eutectic (Gasar) is a novel process for fabricating lotus-type porous metals with oriented pores which is parallel to the solidification direction. By use of the developed 'Gasar' apparatus, lotus-type porous magnesium samples have been fabricated successfully, and the effects of the preheating temperature of the mold and the gas pressures on the porosity, the pore nucleation, the mean pore size and distribution were also studied in the paper. The results show that enhancing of the preheating temperature of the mold can effectively eliminate the pore.-free skin in the lateral part of the ingot. With increasing of hydrogen pressure, the porosity and the mean diameter of the pores will be increased and the uniformity of the size distribution of the pores will be improved.