真空抽出法によるアルミニウム中の分子状水素の挙動と抽出過程

抄録

The vacuum hot extraction (VHE) and the vacuum fusion extraction (VFE) methods were tried. Molecular hydrogen in aluminum having gas pores is extractive by the VHE method. The extraction proceeds through the dissociation, dissolution, diffusion and evolution processes. The molecular hydrogen requires time for extraction so longer than the diffusive hydrogen as 4hrs or more. In the VFE method, molecular hydrogen is completely extracted within 1hr. Hydrogen in aluminum having gas pores is extracted by the VHE method in the following three steps in accordance with elevated temperatures: (i) When the pores 10^-2cm or more in radius in the surface layer up to 13μ in depth attain the internal gas pressure 16.5 atm or more at 250°to 480°C, they grow as blisters and evolves molecular hydrogen. Hydrogen extracted from the blisters is less than 0.04cc/100g. (ii) Hydrogen 0.61cc/100g in solution diffused in aluminum cast in a green sand mold is extracted at 480°to 660°C, Hydrogen over this value forms pores and remains in molecular state. And (iii) The residual molecular hydrogen is extracted at above 660°C.