Effect of pouring temperature on fractal dimension of primary phase morphology in semi-solid A356 alloy  

作　　者：刘政 毛卫民 刘小梅 

机构地区：[1]Jiangxi Nonferrous Metal Processing Engineering Research Center [2]Faculty of Mechanical and Electronic Engineering,Jiangxi University of Science and Technology [3]School of Materials Science and Engineering,University of Science and Technology Beijing

出　　处：《中国有色金属学会会刊：英文版》2009年第5期1098-1103,共6页Transactions of Nonferrous Metals Society of China

基　　金：Project(50374012)supported by the National Natural Science Foundation of China;Project(0650047)supported by the Natural Science Foundation of Jiangxi Province,China

摘　　要：The fractal dimensions of primary phase morphology in semi-solid A356 alloy prepared by low superheat pouring and slightly electromagnetic stirring were calculated,and the effect of pouring temperature on fractal dimension of primary phase morphology in semi-solid A356 alloy was researched.The results indicate that it is feasible to prepare semisolid A356 alloy slurry by low superheat pouring and slightly electromagnetic stirring,and there is an important effect of pouring temperature on the morphology and the grain size of the primary phase in semi-solid A356 alloy,in which the reduction of pouring temperature can obviously improve grain size and shape factor of primary phase in semi-solid A356 alloy under the condition of a certain stirring power.The primary phase morphology of semi-solid A356 alloy prepared by low superheat pouring and slightly electromagnetic stirring can be characterized by fractal dimension,and the primary phase morphology obtained by the different processing parameters has the different fractal dimensions.Solidification of semi-solid alloy is a course of change in fractal dimension.The fractal dimensions of primary phase morphology in semi-solid A356 alloy prepared by low superheat pouring and slightly electromagnetic stirring were calculated, and the effect of pouring temperature on fractal dimension of primary phase morphology in semi-solid A356 alloy was researched. The results indicate that it is feasible to prepare semisolid A356 alloy slurry by low superheat pouring and slightly electromagnetic stirring, and there is an important effect of pouring temperature on the morphology and the grain size of the primary phase in semi-solid A356 alloy, in which the reduction of pouring temperature can obviously improve grain size and shape factor of primary phase in semi-solid A356 alloy under the condition of a certain stirring power. The primary phase morphology of semi-solid A356 alloy prepared by low superheat pouring and slightly electromagnetic stirring can be characterized by fractal dimension, and the primary phase morphology obtained by the different processing parameters has the different fractal dimensions. Solidification of semi-solid alloy is a course of change in fractal dimension.

关 键 词：A356合金 半固态合金 浇注温度 分形维数 相形态 电磁搅拌 晶粒尺寸 形状因子 

分 类 号：TG146.21[一般工业技术—材料科学与工程] TG255[金属学及工艺—金属材料]