Abstract
Many investigations relating to the effect of additive elements on the cast structure of aluminium and its alloys have already been reported.
In this paper, by addition (range 0.01-0.1%) of 39 differenet elements and alloys to the Al-Fe (0.5%) alloy, their effects on grain size and dendritic structure were reoprted. Furthermore basing on the cooling curve recorded in casting procedure, some relation between the grain size and the undercooling degree was discussed. The summerized results are as follows:
1) The elements which were found effective to form fine structure are Ti, B, Zr, Ta, Nb, V, W, Mo and Ti-B, and all these elements react with Al peritectic, while Be, Y, Li and Si present fine structure with eutectic reaction.
2) In regard to the relationship between grain size and undercool ing degree, it can be said that the grain size goes down finer, if the undercooling degree of primary α becomes less.
3) The elements which refine dendritic structure are five, i, e, Ti, Ta, Na, Ca, Ba and mischmetall.
