Abstract
Diffusion couples of aluminium and iron were held in vacuum at 605°∼655°C up to 96 hr. The section crossing through the alloy layer formed between two metals was examined with an optical microscope, a micro-hardness tester, and an electron probe X-ray microanalyser. The results obtained are as follows: (1) The greater part of the alloy layer was the compound of Fe2Al5. (2) The diffusion of aluminium into iron matrix and iron into aluminium matrix was so little that it could not be estimated. (3) The activation energy of diffusion in the growth of the alloy layer was estimated to be 54 kcal/mol. (4) Finally some considerations on the mechanism of the formation and growth of the alloy layer have been made.
