纯Al及亚共晶Al-Si合金基体对吹气法泡沫铝泡孔结构的影响

The influence of pure Al and hypoeutectic Al-Si alloy base materials on the cell structures of aluminum foams produced by gas injection foaming process

采用吹气法制备工艺,研究了纯Al及亚共晶Al-Si合金基体对泡沫铝平均泡孔尺寸、相对密度,平均泡壁厚度等泡孔结构参数的影响。结果显示,亚共晶Al-Si合金基体泡沫铝较纯Al基体泡沫铝具备更佳的泡孔结构,并且平均泡孔尺寸更小,相对密度更低,平均泡壁厚度更薄。而Si含量不同的亚共晶AlSi合金基体泡沫铝之间的差别较小,泡孔结构参数基本一致。分别从合金相图、熔体表面张力,熔体粘度、液膜破裂的平均厚度等角度分析了造成上述结果的原因。研究表明基体金属的种类也会对吹气法泡沫铝的产品质量产生显著影响,是生产中值得重视的一个因素。

Using gas injection foaming process,the influences of pure Al and hypoeutectic Al-Si alloy base materials on the average cell size,relative density,average cell wall thickness and other cell structure parameters of aluminum foams were studied.Compared with the aluminum foams produced from pure Al,the cell structures of the aluminum foams produced from hypoeutectic Al-Si alloy were much better,and the average cell size,relative density and average cell wall thickness of aluminum foams produced from hypoeutectic Al-Si alloy was smaller,lower and thinner.While these cell structure parameters were similar between the aluminum foams produced from different hypoeutectic Al-Si alloys.In terms of alloy phase diagram,surface tension,melt viscosity and the average rupture thickness of liquid films,the related reasons causing the above results are analyzed.This study showed that the kind of base material was an important factor in aluminum foam production,since it would significantly affect the quality of aluminum foams.