Viscosity and surface tension of Al and effects of additional element

Aluminum foam metal was produced directly from the foaming method. In this foaming process, the surface tension and the viscosity of molten Al that were measured by the ring method and the rotational method, respectively, and are the two most important factors. The surface tension and the viscosity were investigated at the temperature range of 660-950 degreesC and the effects of the additional Ca were investigated at the same temperature range. The measured surface tension of the molten Al decreased linearly with the increasing temperature of Ar atmosphere and 1 atm. It follows the function of sigma(T)=842-0.204(T-T-m)[mNm(-1)]. The viscosity of the molten Al ranged from 3.7 to 4.5[mPa(.)s] in the temperature range. The effect of additional Ca elements is that the tendency is decreased from the surface tension and increased from the viscosity. The surface tension value was sigma(2Ca)=530[mNm(-1)] and viscosity value was eta(2Ca)=14[mPa(.)s] at the temperature of 700 degreesC, respectively, when adding 2wt% of Ca.