热处理对Ca增粘泡沫Al-Cu合金力学性能的影响

Effect of Heat Treatment on the Mechanical Properties of Al-Cu Alloy Foam with Ca Tackifier

采用熔体发泡法制备闭孔泡沫Al-2.5Cu和Al-7Cu合金,添加Ca为增粘剂,TiH为发泡剂。结果表明,在200℃等温时效过程中,泡沫Al-2.5Cu合金并未出现时效强化效应,这与Al-2.5Cu合金的时效析出行为不一致。经200℃等温时效处理后,泡沫Al-7Cu合金的屈服强度随着时效时间的延长而提升,但强化效果远不及Al-Cu合金。对比研究泡沫和实体含Ca的Al-Cu合金发现,共晶Al-Cu-Ca金属间化合物均匀分布于铝基体中,导致泡沫Al-Cu合金时效强化效果不理想。因此,时效处理不能有效增强含Ca的泡沫Al-Cu合金。

The cellular Al-2.5 Cu and Al-7 Cu alloys were prepared by melt foaming method with Ca as a tackifier and TiHas foaming agent. The results indicate that during the aging process at 200 ℃, the foamed Al-2.5 Cu alloy has non-aging strengthening effect, which is inconsistent with the aging precipitation behavior of Al-2.5 Cu alloy. After aging treatment at 200 ℃, the yield strength of Al-7 Cu alloy foam is increased with aging time, while the strengthening effect is far less than that of Al-Cu alloy. The comparison between cellular and dense Ca-containing Al-Cu alloy reveal that eutectic Al-Cu-Ca intermetallic compound is evenly distributed in the aluminum matrix, resulting in undesirable strengthening effect. Therefore, aging treatment can hardly strengthen Ca-containing Al-Cu alloy foam.