Abstract
Soft-reduction experiments on the unsolidified steel ingots were conducted to investigate segregation behavior and deformation behavior during reduction. V-type segregation was restrained when soft-reduction was applied under optimum conditions of a reduction value and reduction rate to compensate for the solidification shrinkage. Excess reduction caused inversed V-type segregation, negative segregation (white band) and internal cracks. The reduction rate should be controlled in accordance with the solidification rate of the unsolidified steel ingot. Apparent reduction stress was affected by the fluidity of the liquid core. Stress relaxation during repeated reduction at an interval of 15s was estimated to be about 30%.
