Abstract
A study has been made of the effect of pouring conditions on large inclusions in bottom part of ingot, the following results have been obtained.
1) The pouring tempereture has the strongest effect on the amount of large inclusion.The temperature becomes lower, the amount of large inclusions increases.
2) The rimming time is an important factor next to the pouring temperature.When the rimming time is short, a large amounts of relatively small size inclusions retain, even if the pouring temperature is sufficiently high.
3) The effect of ingot dimension on large inclusions can not be recognized.Ingot dimension negligible factor compared with two factors mentioned above in the ordinary pouring conditions.
4) Factors influencing the composition of large inclusions were confirmed.The relation, however, between the composition and the amount of large inclusions could not be observed.
