Abstract
The running quality of molten aluminium, whose purity is about 99.7%, suddenly decreases by an addition of iron up to about 0.5%, slightly decreases from 0.5 to 1.0% and considerably decreases by 1.5% addition, but gradually increases from 1.5 to 2%. It may be considered that the influence of the solidification range on this quality is observable by about 0.5% addition and is greatest by 1.5% addition, but gradually decreases with an further addition of iron. Those results were obtained under the following condition: the maximum heating temperature 850° and the superheating temperature about 50°.
The influence of the maximum heating temperature on the running quality of the molten aluminium depends on the pouring temperature: when the superheating temperature, i.e. the difference between the melting point and the pouring temperature, is over 55° the running quality of molten aluminium is superior in the following order of the maximum heating temperature, 850°, 900°, 800° and 750°, but when the superheating temperature is below 45°, the quality is superior in the order of 800°, 900°, 850° and 750° In the neighbourhood of the superheating temperature 50°, the influence of the maximum heating temperature is not so great.
In these experiments, the temperature of the metallic mould for the measurement is about 70°.
