Hot Ductility Of Directly Cast Steels With Different Carbon Contents

Abstract

Tensile samples of Nb containing steels with different carbon contents have been cast in situ, cooled to test temperatures in the range 800-1000 °C and tested at a strain rate of 3x10 s . The austenite grain sizes of the melted and resoldified samples showed real dependency on the carbon content of the steel. This resulted in variation in hot ductility values obtained for the steels examined, as increasing the carbon level from 0.014% through 0.1% to 0.14% has deteriorated the hot ductility of the steel due to grain coarsening, but a further increase to 0.18% C produced improvement due to grain refining. The effect of the carbon content of the steel on the austenite grain size has been explained in terms of the peritectic reaction.