Grain refinement of AZ31 magnesium alloy by new Al-Ti-C master alloys  

作　　者：韩广 刘相法 丁海民 

机构地区：[1]Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials,Ministry of Education,Shandong University

出　　处：《中国有色金属学会会刊：英文版》2009年第5期1057-1064,共8页Transactions of Nonferrous Metals Society of China

基　　金：Project(50625101) supported by the National Natural Science Foundation for Distinguished Young Scholars of China;Project(106103) supported by Key Project of Science and Technology Research of Ministry of Education of China

摘　　要：New Al4C3-containing Al-Ti-C master alloys (Al-0.6Ti-1C and Al-1Ti-1C) were developed by introducing Ti element into Al-C melt using melt reaction method,in which most of the TiC particles distribute around Al4C3 particles. It is believed that most of the C firstly reacts with Al melt and form Al4C3 particles by the reaction Al(l)+C(s)→Al4C3(s),and after adding Ti into the Al-C melt,the size of Al4C3 particles is decreased and the distribution of Al4C3 is improved through the reaction Ti(solute)+Al4C3(s)→ TiC(s)+Al(l). With the addition of 1% Al-1Ti-1C master alloy,the average grain size of AZ31 is reduced sharply from 850 μm to 200 μm,and the grain morphology of α-Mg transits from a fully-developed equiaxed dendritic structure to a petal-like shape. Al-C-O-Mn-Fe compounds are proposed to be potent nucleating substrates for primary Mg. Appropriate addition of Ti is believed to increase the grain refinement efficiency of Al4C3-containing Al-Ti-C master alloys in AZ31 alloy.New A14C3-containing A1-Ti-C master alloys （Al-0.6Ti-1 C and Al-1Ti-1 C） were developed by introducing Ti element into A1-C melt using melt reaction method, in which most of the TiC particles distribute around Al4C3 particles. It is believed that most of the C firstly reacts with Al melt and form Al4C3 particles by the reaction Al（1）＋C（s）→Al4C3（s）, and after adding Ti into the Al-C melt, the size of A14C3 particles is decreased and the distribution of Al4C3 is improved through the reaction Ti（solute）＋Al4C3（s）→ TiC（s）＋Al（1）. With the addition of 1% Al-1Ti-IC master alloy, the average grain size of AZ31 is reduced sharply from 850 μm to 200 μm, and the grain morphology of α-Mg transits from a fully-developed equiaxed dendritic structure to a petal-like shape. Al-C-O-Mn-Fe compounds are proposed to be potent nucleating substrates for primary Mg. Appropriate addition of Ti is believed to increase the grain refinement efficiency of Al4C3-containing Al-Ti-C master alloys in AZ31 alloy.

关 键 词：AZ31镁合金 TIC颗粒 中间合金 晶粒细化 AL4C3 熔体反应法 铝 颗粒分布 

分 类 号：TG146.21[一般工业技术—材料科学与工程]