铝及其合金熔体的增黏及泡沫化特性

研究了纯铝、普通铝硅合金和新型多组元铝合金的增黏和泡沫化特性．这三者加入Ca增黏后的物相组成和发泡后的气泡壁微观组织以及三者熔体的表面张力．结果表明：Ca加入后，经过搅拌形成的大量弥散分布的细小Al-Ca中间化合物颗粒快速增加了纯铝以及新型多组元铝合金熔体的黏度，而Ca加入普通铝硅合金中与Si等元素形成较大的颗粒，因而增黏效果不如前两者；Ca的加入也显著降低新型多组元铝合金和纯铝熔体的表面张力，普通铝硅合金降低不多；在相同的表观黏度下，表面张力的差异是引起纯铝．普通铝硅合金、新型多组元铝合金等三种熔体泡沫化特性差异的主要原因．

Comparing of thickening and foaming characters of Al and Al alloy

The thickening and foaming histories of Al, Al-Si alloy, innovated AI alloy melts were measured. The composition of the three melts thickened by calcium and the micro structure of cell wall were investigsted. The surface tension of the three melts was measured by bubble-pressure method. The results show that the viscosity of melt Al and innovated Al alloy augments fast since numerous Al-Ca intermediate compounds in small particle size are homogenously dispersed. While in Al-Si melt, compounds comprising Ca, Si, Al and other elements forms in relatively large particle size, and thickening in Al-Si melt is less effective compared to AI melt and innovated AI alloy melt. Under the same ingredient of Ca, the surface tension of Al and innovated Al alloy melt decrease dramatically, the surface tension of melt Al-Si alloy only has little drop. The discrepancy of foaming characteristics among the melt Al, Al-Si alloy and innovated AI alloy is derived from the difference of surface tension.