Activation of aluminum metal and its reaction with water

Aluminum-based metal composites doped with gallium, indium, zinc, or tin and their chemical properties as hydrogen-generating materials in reactions with water were studied by powder X-ray diffraction, DTA, and EDX. Samples containing up to 80 wt.% Al were demonstrated to be multiphase mixtures containing dispersed grains of aluminum-based solid solutions as well as components of a foundry alloy, viz., zinc, tin, and InSn4, and a liquid phase, which is a eutectic with a melting point of 6 °C. The dependences of the rate and amount of hydrogen generated on the quantitative and qualitative composition of alloys as well as on the time and conditions of their storage were examined. Reasons for deactivation of alloys in reactions with water are considered.