FABRICATION AND PROPERTIES OF HIGH-CHROMIUM CAST IRON DISPERSED STEEL MATRIX COMPOSITE

Composites with high-chromium cast iron (HCCI) dispersed in a steel matrix were prepared using the multilayer rolling-forming method. The macroscopic morphology, microstructure and tensile properties of the bimetal composites were analyzed. The experimental results showed that brittle HCCI layers were necked and broken into uneven blocks or granules after hot-rolling forming. The fractured HCCI was encased in carbon steel completely, and the two metals achieved good metallurgical bonding. The Fe, Cr, Mn and C elements were diffused at the interface. The tensile strength of the composite was better than that of the as-cast iron. During the process of tensile deformation, the composite displayed a complex crack propagation rather than a fracture caused directly by brittleness. The damage tolerance and energy absorption capacity of the bimetallic composite were improved with a decentralized structure.