【作者】 红梅； 毛协民； 欧阳志英；

【Author】 HONG mei, MAO xie-min , OUYANG Zhi-ying (School of Materials Science and Engineering, Shanghai University, Shanghai 200072, China)

【机构】 上海大学材料学院；

【摘要】 采用减压凝固法研究了Sr变质对A356熔体氢含量的影响。结果表明,经Sr变质处理后合金氢含量和减压凝固试样断面气孔的数量明显高于未变质处理的合金。这是因为Sr加入到A356合金后,在铝熔体表面氧化膜中,出现有锶的氧化物。由于α<1的锶氧化物的存在,使A356合金熔体的表面氧化膜变得疏松,易开裂,加大了新鲜铝液暴露在大气下的几率,降低了原氧化膜的防二次污染作用,从而导致了熔体含氢量的增加,吸氢倾向加重。更多还原

【Abstract】 The paper has analyzed the influence of the Sr modification upon hydrogen content in the A356 melt by adopting the reduced pressure test. The results indicated that the hydrogen content and the porosity quantity in the section of Strontium - modified samples are obviously higher than those unmodified. This is because the oxide film at the A356 melt surface was almost composed of SrO, but this oxide make the surface oxide film looser had been loosened and cracked owing to the enrichment of the Strontium of the oxide film at the surface of the melt, which also will influence the role in resistant to the melt decontaminated that the oxidiferous film plays.更多还原