Analysis of high-Cr cast iron/low carbon steel wear-resistant laminated composite plate prepared by hot-rolled symmetrical billet
This study developed a new technology for preparing high-chromium cast iron (HCCI)/low-carbon steel (LCS) wear-resistant composite plates by hot rolling at a 1050 °C and a rolling speed of 0.2 m/s. The effects of different rolling reductions (30%, 45%, and 60%) on the microstructure (interface and HCCI layer) and mechanical properties (bonding strength, hardness, and wear resistance) of the composite plate were studied. SEM images showed that when the reduction was increased, no impurities and interlayers were found between the microscopic interfaces after hot rolling, and the bonding interface exhibited a wave-like shape. EDS analysis showed that the Cr element diffusion between two metals after hot rolling was promoted when the reduction was increased, thereby improving the bonding quality under the same rolling temperature and rolling speed. Experiments showed that due to the stress release effect of the LCS of the cladded layer, the macro-slab shape after hot rolling performed well, and the brittle HCCI layer underwent thermoplastic deformation without cracking. Moreover, the increase of rolling reduction improved the bonding quality. As the rolling reduction was increased, the volume fraction of Cr-carbides in the HCCI layer also increased, resulting in an increase of hardness and wear-resistance.