Method for directional solidification of a molten material and apparatus

Abstract

A method for directional solidification (DS) of a molten material, and an apparatus therefor. The method generally entails the use of a container having a base and peripheral wall that define an interior of the container, an induction coil for heating the contents of the container and generating an electromagnetic field, and means for controllably separating the container from the heating means and the electromagnetic field, such as by withdrawing the container from the heating means and electromagnetic field. Using such an apparatus, a material is heated within the container to yield a melt that is substantially prevented from contacting the wall of the container as a result of being at least partially levitated by the electromagnetic field. The container is then separated, e.g., withdrawn from the heating means and the electromagnetic field so as to cause directional solidification of the melt while the majority of the melt remains spaced apart from the wall of the container, yielding a directionally solidified article whose composition has not been significantly affected by reactions with the container. The invention is particularly directed to the production of DS ingots of high temperature materials containing one or more reactive elements.