Evolution of solidification structure of hypereutectic Al-Si alloy under a novel low-voltage alternating current pulse

摘要：

　　The effect of a novel low-voltage alternating current pulse(ACP)controlled by transformer and silicon controlled rectifier on the solidification structure of Al-20%Si alloy was investigated.The results indicated that the remarkable segregation of primary Si occurred during the solidification,and even dendrites of α-Al phase appeared at the center of samples under ACP.The thickness of segregation layer decreased first and then increased with current density increasing from 0 to 300 Acm-2.The primary Si existed with long pole or five petal star-shaped without ACP.However,the morphology of primary Si phases changed to block under ACP,and the sizes of blocky Si decreased obviously with increasing current density from 110 to 300 Acm-2.The formation mechanism of the structure of hypereutectic Al-20%Si alloy was also discussed under ACP.

关键词： A low-voltage alternating current pulse Macrosegregation Morphology of Si Al-Si alloy

作者: ZHANG Li-min ZHANG Rong LI Ning CHEN Wen-jing DU Li-fei

作者单位: Key Laboratory of Space Applied Physics and Chemistry,Ministry of Education,School of Science,Northwestern Polytechnical University,710072,Xian,China

会议类型: 国际会议

会议名称: The 7th International Conference on Electromagnetic Processing of Materials(第七届冶金与材料电磁过程国际大会)

会议地点: 北京

会议语种:英文

页码: 1-4

在线出版日期: 2012-10-22（万方平台首次上网日期，不代表论文的发表时间）