【摘要】 为进一步优化和精确控制泡沫铝的孔结构，本文对熔体发泡过程的增黏阶段设计了正交试验，通过对所得样品孔隙率和孔结构分析，确定Ca添加量为2wt%，增黏搅拌速度在700 r/min，增黏温度为700℃，增黏搅拌时间4 min为最佳增黏工艺参数，四因素中Ca添加量对孔隙率影响最大。样品8的孔半径及孔圆形度最佳，试样8密度为0.45 g/cm³，孔隙率为83.2%，孔圆形度集中在0.8～0.9之间，占总体比例51.5%，孔的等效半径集中在0.5～1 mm之间，占总体的比例54.7%。增黏搅拌温度提高孔径变大，增黏搅拌速度增加气孔圆形度更好。对其机理进行研究分析表明：Ca与Al反应生成金属间化合物Al₄Ca对熔体增黏起主要作用；生成相会阻碍气孔生长，影响生长方向，使气孔长成纺锤形。更多还原

【Abstract】 In order to further optimize and accurately control the pore structure of aluminum foam, orthogonal experiments were designed for the viscosity increasing stage during the melt foaming process. Through the analysis of the porosity and pore structure of the obtained samples, it was determined that the optimal viscosity increasing parameters were 2% Ca addition, 700 r/min viscosity increasing stirring speed,700 ℃ viscosity increasing stirring temperature and 4 min viscosity increasing stirring time. Among the four factors, Ca addition had the greatest influence on porosity. The pore radius and roundness of the sample 8were the best. The density of the sample 8 was 0.45 g/cm³, the porosity was 83.2%, the pore roundness was concentrated between 0.8 and 0.9, accounting for 51.5% of the total, and the equivalent radius of the pores was concentrated between 0.5 and 1mm, accounting for 54.7% of the total. When the viscosity enhancement stirring temperature was increased, the pore size became larger; when the viscosity enhancement stirring speed was increased, the roundness of the pores was better. The mechanism of the reaction between Ca and Al showed that the intermetallic compound Al₄Ca played an important role in increasing the viscosity of the melt.The formation phase obstructed the growth of bubbles, affected the growth direction, and made bubbles grow into spindle shapes.更多还原