Controlling centre segregation and shrinkage cavities without internal crack in as-cast bloom of steel GCr15 induced by soft reduction technologies

Abstract

ABSTRACT To investigate the alleviation technology of internal cracks, center shrinkage cavities and center segregation of as-cast bloom simultaneously, a three-dimensional finite element model was developed to calculate and analyze the strain fields and deformation behavior of as-cast bloom induced by soft reduction process. In the present work, a multi-stage mechanical soft reduction (MSR) has been developed to simultaneously alleviate center segregation and shrinkage cavities without internal cracks, which aims to provide theoretical basis for improving the internal quality of high carbon as-cast blooms induced by soft reduction technologies. According to the experimental results, the internal cracks were effectively alleviated and center shrinkage cavities were nearly eliminated by optimum designed experiments, the homogeneity and compactness of as-cast bloom can been remarkably improved in comparison with that induced by the conventional soft reduction process. The carbide size and bandwidth of the carbides in the hot-rolled wire were both decreased.