Abstract
A quenching technique was applied to study the formation of the central equiaxed zone in ingots. Two alloy systems were studied, lead with 2 pct Sb and aluminum with 2 pct Cu. It was found that the central zone can be regarded as composed of two zones, one formed from the bottom by sedimentation and the other formed by the adhesion and further growth of crystals at the vertical solidification front. The columnar-to-equiaxed transition at the vertical solidification front is caused by the development of individual equiaxed grains and not by the remaining melt becoming more and more mushy. It is suggested that the branched columnar zone often observed in commercial ingots is identical to the equiaxed zone formed at the vertical solidification front.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have