Effect of two-liquid bimetal wear resistance plate thickness on microstructures and properties of composition layer

Two-liquid bimetal composite casting through the liquid film bond technology can realize large metallurgical composite plane to prepare the two-liquid bimetal wear resistance plate between low carbon steel and high chromium cast iron, which can effectively avoid the insufficient heat quantity of the later poured high temperature liquid metal with the conventional liquid-liquid composite technology. The microstructure and composition of the composition layer were detected with SEM and EDS. The results show that, the sequence of the microstructure from the low carbon steel to the high chromium cast iron is as follows: low carbon steel→pearlite transition layer→composition layer→high chromium cast iron transition layer. The Vickers hardness of composition layer region is from 345 to 1260. The microstructure of the composition layer is γ-Fe and granular carbide. The morphology of γ-Fe in high chromium cast iron layer presents the distinct directional dendritic crystal growth that is perpendicular to the composition layer, but the γ-Fe directivity gradually disappears with the increment of the wear resistance plate thickness. The temperature field mathematical model of the low carbon steel is preliminarily developed for providing a quantitative analysis to the two-liquid bimetal composition technology.