The Development of a Continuous Rheocaster for Ferrous and High Melting Point Alloys.

Abstract

A new continuous rheocasting process for steels and high temperature alloys has been developed by Inland Steel incorporating a dual chamber casting machine utilizing separate electromagnetic stirrers around each chamber. The caster parameters were varied in a series of experiments to determine the optimum combination to provide a fine degenerate dendrite size, small peripheral dendritic zone, and minimum percent dendricity. The optimized process produces a degenerate dendrite size of about 80 microns with a peripheral dendritic zone about 1.5 mm thick and no dendricity. A series of casts was made of 12 different steel and high temperature alloys to determine the capability of the Inland Steel rheocaster to provide a satisfactory rheocast structure on various alloys. The rheocaster produced an acceptable rheocast structure for all alloys cast. Comparison of the cast structure of the Inland Steel rheocast material to conventional continuous cast material has shown that highly alloyed materials can be cast using rheocasting and provide a fine, homogeneous, and unsegregated cast structure. This is not the case for conventional continuous casting processes available currently.