Influence of phosphorus micro-segregation on ferrite structure in cast strips of 0.1 mass% C steel

Abstract

Cast strips of 0.1 mass% C steel with or without phosphorus addition have been characterized by electron back-scattering diffraction pattern (EBSP) measurements. Then the formation of globular ferrite structure was discussed. EBSP analysis combined with optical microscopy clearly showed that a globular grain was fitted to be an α-ferrite grain. The EBSP analysis suggested that the retained-δ grain grew predominantly in the γ-grain and formed the globular α-ferrite during cooling. The microtexture in the globular ferrite structure depended highly on the solidification structure. It is important to scatter the primary dendrite growth direction into neighboring areas to develop fine prior-γ and α structures for the cast strip of high-phosphorus steel.