Dispersion of TiH2 foaming agent in precursor for two-step foaming process of aluminum foam

The dispersion of TiH2 in the melt route precursor for two-step foaming process of aluminum foam was studied, including the measurement of aluminum melt viscosity, the effects of processing parameters on the dispersion of TiH2, etc. The results show that 610°C is the key point of the temperature-viscosity relationship of aluminum foam. While the melt temperature is below 610°C, the viscosity elevates greatly with decreasing temperature. While melt temperature is above 610°C, the viscosity elevates slowly with decreasing temperature. The uniform of foaming agent is improved with increase of melt temperature, stirring speed and dispersing time. However, the aggregation of TiH2 still exists stirred at rotation speed 3000 r/min for 30 s. Three approaches are found to be effective to improve the uniform of TiH2 in the melt route precursor: Disperse TiH2 in the viscosity-temperature non-sensitive area of aluminum alloy, density the cast precursor by pressing, and use a rotation speed higher than 3000 r/min.