采用新型发泡剂制备了泡沫铝,研究了包覆改性和混合改性两种改性方式对新型发泡剂在铝熔体中分散性的影响。结果表明,采用Al溶胶和Si溶胶对新型发泡剂进行包覆改性处理,发泡剂分散性差,所制备的泡沫铝存在较多大孔和裂纹;采用TiB2粉末和AlSi合金粉末混合改性处理新型发泡剂时,发泡剂分散性良好,并且随着TiB2和AlSi含量的增加得到的泡沫铝样品裂纹明显减少、泡体趋于均匀,但孔隙率逐渐降低。相比较而言,合金粉末混合改性法比溶胶包覆改性法使发泡剂的分散更均匀,制备的泡沫铝裂纹较少,且泡体结构较均匀。
Foam aluminum was prepared by novel foaming agent. Effects of coating modification and mixing modification on the dispersibility of novel foaming agent in aluminum melt were studied. Experimental results show that when the novel foaming agent is modified by coating alumina sol or silica sol, the poor dispersibility of foaming agent leads to more large holes and cracks of aluminum foams; when the novel foaming agent is modified by mixing with TiB2 or AlSi, the dispersibility of foaming agent is preferable, and cracks of aluminum foams reduce obviously and distribution of pores tends to uniform with TiB2 or AlSi content increases, but the porosities of aluminum foams decrease gradually. Compared with coating modification, the dispersibility of foaming agent by mixing modification is better, cracks of aluminum foams are less and pore structure is more uniform.