小孔径泡沫铝的制备及压缩性能研究

在常规熔体发泡法基础上,采用添加0.5%Mg(质量分数,下同)以降低表面张力;发泡剂400 ℃,6 h+500℃,1 h氧化预处理以协调发泡剂分散均匀性与发泡过程关系;发泡搅拌60s以破碎初始气泡等措施,成功制备出了平均孔径1.3 mm、孔隙率70.5%、结构均匀的小孔径泡沫铝.泡沫铝及Al-9Si泡沫的压缩性能分析表明,随平均孔径减小,泡沫铝的屈服强度、致密化应变和能量吸收能力均明显提高,泡沫铝压缩性能随孔径减小而提高,与泡沫铝的孔结构因素及孔结构均匀性有关.

Fabrication and Compressive Properties of Al foam With Fine Cell Structure

Based on the general melt foaming processing, small-size Al form with 1.3 mm average cell diameter, 70.5% porosity and uniform cell structure was fabricated by other measures including adding alloying element 0.5% Mg(mass fraction, similarly hereinafter) to decrease Al melt surface tension, pre-heating forming agent TiH2 by 400 ℃, 6 h+500 ℃, 1 h to harmonize the relationship between forming agent dispersion and decomposition at the stage of forming processing and foaming stirring for 60 s to break the initial bubbles. The compressive property tests of fabricated Al foams and Al-9Si foams suggest that with the decrease of the average cell diameter, two kinds of foam's yield strength, densification strain and energy absorption increase obviously. The reasons for these improvements are associated with the cell structure itself and the cell structure uniformity.