Numerical Simulation on the dendritic spacing and microporosity in A356 alloy ingot
A stochastic mathematic model contained the effects of dendrite morphology, solidification shrinkage and dissolved gases was formed to simulate microporosity formation and growth. Microporosities appear in the interspaces of primary dendrites as well as secondary dendrites from microscopic view of A356 aluminum alloy experimental ingot with a metal mold. In the past literatures it took the volumetric fraction of microporosities as a function of the local density. In the present work a single pore was predicted about the size and distribution. The combination of shrinkage and dissolved gases drives porosities development in the dendritic space. The dendritic growth influences the pore pattern and the dendritic spacing is the main parameter. For shrinkage and dissolved gases causes, the favorable one is determined by dendritic spacing, also the local cool rate and tip growth rate. The dense degree of the experimental ingots in different casting conditions is discussed. The variations of dens degree from the measured values in different casting conditions are similar to that of porosity volume fraction from the predicted results.
dendrite arm spacing microporosity gas pore simulation dens degree
Pei Zhang Fengshan Du Zhiqiang Xu Lingling Zhao
Mechanical Department of YanShan University, Qinhuangdao Hebei 066004 P.R.of China
国际会议
郑州
英文
2007-10-23（万方平台首次上网日期，不代表论文的发表时间）