(东北大学 材料与冶金学院， 沈阳 110004)
摘 要: 以熔体直接发泡法制备闭孔泡沫铝材实验为基础，通过获得不同实验阶段的泡沫铝样品， 以及对实验样品切面或断面进行观察和分析， 描述了在熔体发泡法制造泡沫铝过程中TiH2加入熔体后的分解过程， 原始气泡的形成方式以及产生的气泡和未分解TiH2的存在状态； 解释了气泡进一步长大的原因和未分解的TiH2如何释放气体； 表述了气泡的合并和无泡层的形成。结果表明： 未分解的TiH2颗粒粘附在熔体内形成的较小气泡表面，即气/液相界面上； 在恒温发泡过程中气泡壁上吸附的尚未分解的TiH2颗粒进一步分解并向气泡内释放气体，使气泡长大； 相邻气泡壁上的TiH2局部浓度较高并集中释放气体，导致气泡壁破裂及气泡间的合并。
关键字: 泡沫铝； 闭孔型； 熔体发泡法； 气泡
closed-cell aluminum foam
（ School of Materials and Metallurgy, Northeastern University, Shenyang 110004, China）
Abstract: The closed-cell aluminum foam was fabricated by direct foaming in melt. Through sampling aluminum foam in different stages the cross-section of them were observed and analyzed. It was explained how TiH2 was decomposed after entered into the melt, how initial bubbles were formed and what was the state that generated bubbles and undecomposed TiH2 lay in. The reason that why bubbles grew and how the gas was released from undecomposed TiH2 were stated. The merging of bubbles and formation of bubble-free layer were also described. The results show that the particles of undecomposed TiH2 adhere to the surface of small bubbles formed in the melt, that is on the surface of gas/liquid phase. During foaming of constant temperature, the particles of undecomposed TiH2 adhering to cell wall decompose and release gas into bubbles and make them grown up. If the local concentration of TiH2 of adjacent cell wall is high and it releases gas intensively, fracture of cell wall and merging of bubbles will be generated.
Key words: aluminum foam; closed cell; foaming in melt; bubble
