Wetting balance test is known to be the most versatile method to evaluate wettability during soldering process, because it provides quantitative information and time dependent wetting behavior. There are many other studies exist related with the wetting force, however, as to wetting time, there are few theoretical backgrounds and mathematical analysis. In this study, the wetting time is focused on a wettability index. The wetting curve, which shows time dependant wetting behavior, is predicted by using computer simulation and compared with oil experiment also, the mechanism of meniscus rise is analyzed. As a result, relationship of calculated and measured wetting curve can be obtained. It is found that the viscosity of a liquid is the major variable that determine the wetting time and wetting rate.

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Magnesium alloys have been well known as active metals. Thus, magnesium alloys in molten state must be handled with extreme care during melting and casting. In this study, water model experiments and numerical analyses were carried out to optimize a pipe flow that can transport magnesium alloys in molten state safely from melting to casting furnace. Especially, during a transportation of molten magnesium alloys, a flow pattern in a pipe becomes important, because the interface between air and melt can be the source of the metal oxidation, and therefore, an air/melt interface area must be minimized. For these purposes, two vessels connected with a long pipe having two elbows with different diameters and radii of the curvature were simulated as melting and casting furnace for magnesium alloys. Optimized conditions with minimized air/melt interface area for the melt transportation were discussed in several pipe configurations.