摘要
采用单辊甩带方法制备了Al-10%Sr激冷薄带中间合金。利用DSC、SEM、XRD等测试手段研究了激冷薄带Al-10%Sr中间合金对A356铝硅合金的变质效果。结果表明:Al-10%Sr激冷薄带中间合金的相组成中出现了单质Sr,并在衍射角0°～14°间出现了非晶的漫散峰。采用Al-10%Sr激冷薄带中间合金对A356合金变质处理后,其共晶开始温度由576℃降低到571.3℃,共晶潜热则增加了39.2 J/g;变质后的A356合金经T6处理后,其共晶硅多呈点状(低倍)或球状、卵状(高倍),基体组织中树枝状α(Al)固溶体组织明显增多,初晶Si相消失;电导率(20.07 S/μm)比A356合金提高了14.9%,变质效果良好。
Ribbon of Al-10% Sr mater alloy were prepared by single roller melt-spinning.DSC,SEM and XRD were used to examine the modification efficiency of the Al-10% Sr alloy melt-spun ribbon on microstructure of A356 alloy.The results indicate that Sr melts is found in the melt-spun ribbon of Al-10% Sr master alloy and the diffuse scattered peak of amorphous appears between 0° and 14° in the XRD patten.The eutectic starting temperature of A356 alloy modified by Al-10% Sr melt-spun is lowered from 576 ℃ to 571.3 ℃,the eutectic latent heat increases by 39.2 J /g.After T6 heat treatment,the eutectic silicon of A356 alloy mostly exhibits dot-like spherical shape at lower magnification and spawn-like shape at high magnification.Dendritic α（Al） solid solution is obviously increases in the matrix,the primary Si phase disappears.Conductivity of the modified A356 alloy by Al-10% Sr melt-spun ribbon is higher than that of un-modified A356 alloy by 14.9%.
出处
《材料热处理学报》
EI
CAS
CSCD
北大核心
2010年第10期16-20,25,共6页
Transactions of Materials and Heat Treatment
关键词
共晶硅
变质
电导率
eutectic-silicon
modification
conductivity
