Closed-cell aluminum foam specimens with different densities were fabricated successfully by direct foaming of melt controlling temperature and stirring parameters,using in-situ Mg2Si/Al composite as matrix and CaCO3 as blowing agent.The results of quasi-static compression test of specimens showed that,quasi-static compression of Mg2Si/Al composite foam possesses typical three-stage characteristic of metal foam compression; compression yield strength and plateau stress of specimens increased with their densities increasing;the decrease of stress near the yiel-ding point and serrations in stress plateau expose brittle-rupture characteristic of cell walls.Through artificial ageing heat-treatment,compression yield strength of Mg2Si/Al composite foam increased remarkably.It was found that ductile Al matrix was rent by the thick pseudo-eutectic Al+Mg2Si,through observation of microstructure of cell walls.%采用熔体发泡法,以原位自生Mg2Si/Al复合材料为基体,CaCO3作发泡剂,通过控制温度和搅拌参数,成功制备出不同密度的闭孔泡沫铝.通过静态压缩性能试验发现:泡沫Mg2Si/Al复合材料的压缩过程具备泡沫金属压缩变形的三阶段(弹性变形、应力平台区、致密化阶段)特征；压缩屈服强度和平台应力均随密度增加而增大；屈服点附近应力值下降,应力平台区出现锯齿波形,暴露出孔壁的脆性破裂特征.经过人工时效热处理,泡沫Mg2Si/Al复合材料的屈服强度显著增大.通过观察孔壁的微观组织发现,Al基体被孔壁中粗大的Al+Mg2Si伪共晶组织所割裂.
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