(中南大学 冶金科学与工程学院， 长沙 410083)
摘 要: 研究了一种在泡沫铝制备过程中可替代TiH2及ZrH2类发泡剂的新型发泡粉末的热分解行为， 探讨该新型发泡剂加入量及发泡温度等因素对泡沫铝孔隙率的影响。 研究表明： 该新型发泡材料具有分解温度范围宽及分解过程缓慢的特点。 当采用该发泡剂时， 泡沫铝制备过程无需额外加入金属Ca类增粘剂； 随发泡温度的升高， 泡沫铝的孔隙率先升高后下降； 随发泡剂量的增多， 发泡体中的无泡层逐渐减少， 当发泡剂的加入量在1.40%以上时， 发泡体中的无泡层消失； 在发泡温度740 ℃、 发泡剂加入量1.40%～2.20%、 搅拌时间3 min、 保温发泡时间5 min的条件下， 可以制备出孔径2～5 mm， 孔隙率60%～80%， 孔隙基本均匀且无实心体的泡沫铝。
关键字: 泡沫铝； 发泡剂； 热分解行为； 无泡层； 孔隙率
（School of Metallurgical Science and Engineering, Central South University, Changsha 410083, China）
Abstract: The thermal decomposition behavior of a novel foaming agent substituting for TiH2 and ZrH2 during the preparation process of aluminum foam was investigated. The effects of the foaming agent content and foaming temperature on the porosity of aluminum foam were also discussed. The experimental results show that the novel foaming agent has a wide decomposition temperature range and a slow decomposed rate; the extra viscosifier such as Ca is unnecessary while using this foaming agent; the porosity firstly increases and then decreases with foaming temperature rising; the free-bubble layer in material decreases with foaming agent addition increasing, and the free-bubble layer disappears while foaming agent addtion is more than 1.4%; an aluminum foam product characterized by no free-bubble layer, uniform bubble distribution, pore sizes of 2-5 mm and porosity of 60%-80% can be obtained under the conditions the foaming temperature 740 ℃, foaming agent addition 1.40%-2.20%, stirring time 3 min and foaming time 5 min.
Key words: aluminum foam; foaming agent; thermal decomposition behavior; free-bubble layer; porosity
