Effect of Solidification Variables on the Tensile Property of 2.8 wt% C–26 wt% Cr White Iron

Abstract

The present study aimed to investigate the increasing solidification rate during directional solidification developed from in situ composites of M7C3/austenite eutectic, to in situ composites with a small portion of dendrites, and to partial in situ composites with equiaxed structures. M7C3 fibre aligned along the solidified direction in the in situ composites; however, its orientation and shape became irregular among the dendrites. In situ composite structure has higher tensile strength than partial in situ composite or equiaxed material. Crack initiation in the fibre occurred because the fibre could not accommodate the deformation of the matrix under tensile stress. The tensile fracture was caused by both crack initiations in the M7C3 fibre or at the randomly oriented particles, and the crack propagation to matrix.