2013 年 85 巻 3 号 p. 147-154
The change of the eutectic silicon inter lamellar spacing in Al-Si alloy is one of the factors changing the alloy's mechanical properties. This paper aimed to clarify the effects of the relationship between the eutectic solidification time (t) and eutectic cell number (n) on this eutectic silicon inter lamellar spacing (λ) on the surface of a permanent mold casting made of Al-7%Si alloy. The results are as follows.
1) The eutectic cell number (n) is affected by the quantity of nuclear matter in the molten metal and super cooling caused by the mold.
2) The eutectic silicon inter lamellar spacing (λ) increases with the increase in the eutectic cell number (n) and eutectic solidification time (t).
3) The parameters in the above 2) were found to have the following relationship. λ = k・n1/4・t1/2.