变质工艺对亚共晶Al-Si合金共晶硅细化的影响  

Influence of Modification Process on Eutectic Silicon Refinement of Hypoeutectic Al-Si Alloy

作　　者：姚巍[1] 董剑雄 王云利[1] 李美[1] 王建华[1] 常智杰[1] 杨贵海[1] 王建军 

机构地区：[1]包铝股份公司电解三公司,内蒙古包头014046 [2]东海铝业公司,山东龙口265718

出　　处：《铸造》2007年第10期1107-1109,1112,共4页Foundry

摘　　要：研究了工业生产Sr变质亚共晶Al-7%Si合金时,变质剂含量、变质温度、变质时间、浇注温度等工艺参数对合金共晶硅细化及其性能的影响。结果表明,在大规模工业化生产中,上述工艺参数严重影响共晶硅的变质效果。采用Al-10%Sr对亚共晶Al-7%Si合金进行变质,在w(Sr)=0.015%时,保温40min后,共晶团内的Si完全成为圆颗粒状,尺寸为5～10μm,达到最佳变质效果。采用Sr变质亚共晶Al-7%Si合金最佳变质温度为700℃,变质后共晶硅组织分布均匀;浇注温度为640℃时的铸件宏观组织最佳,晶粒度可稳定的达到2级,升高浇注温度,晶粒度提高。精炼后,变质时间为30～60min进行浇注,试样针孔度最小,熔体洁净程度高。This paper researches the influence of modification process parameters （such as modification agent content, modification temperature, modification time and casting temperature etc.） on eutectic silicon refinement when carrying out Sr modification treatment on hypoeutectic Al-Si alloy. As a result of research, during large-scale industrial production, above-mentioned process parameters seriously influence the deterioration effect of eutectic silicon. Taking Al-10%Sr as modification agent of hypoeutectic Al-Si alloy, when w（ Sr ）=0.015% and keeping temperature for 40 minutes, the silicon in eutectic crystal cluster has been fully spherical with size 5-10 μm, reach the best modification effect. When carrying out Sr modification treatment on hypoeutectic Al-Si alloy, the best modification temperature is 700 ℃, in this case, the modification eutectic crystal silicon structure becomes uniform; the cast macrostructure is best with casting temperature 640℃, the grain degree can constantly reach class 2, higher casting temperature, high grain degree. In case of modification time 30-60 minutes, the pinhole degree of sample is smallest, with high metal purification degree.

关 键 词：亚共晶Al-7%Si合金 Sr含量 变质 浇注温度 针孔度 

分 类 号：TG166.3[金属学及工艺—热处理]