Abstract
It has been found that 3D-CAD is a powerful tool for analyzing the apparent pattern of solidification structure. Using 3D-CAD, the apparent patterns of model dendrites have been analyzed in this study. The effect of distribution of dendrites and the morphology of secondary dendrite arms on the apparent pattern have been investigated. As far as secondary dendrite arms form, it has been found that it can be recognized the ghost lines and it is possible to measure the characteristic parameters of ghost lines, η, ξ and γ, which are defined previously. Therefore, we can analyze the spatial relation of dendrite using these characteristic parameters of ghost lines. On the other hand, when the solidified structures are constituted by cells, which have no secondary arms, ellipses stand in a row on the cross section. Therefore, one could recognize the apparent pattern. However, it is not possible to analyze the spatial relation of the cell, since the ghost lines cannot be specified because of the distribution of cells.