Thermal Stability of High-Chromium Cast Iron

High-chromium cast iron (HCCI) is often used for manufacturing parts operating at a high temperature and high specific pressure, for example, for spinning tools or cast rolls for hot and cold rolling. As a rule, castings of chromium iron have a composition close to the eutectic one, which is responsible for their low strength and impact toughness but provides the best wear resistance. By lowering the carbon equivalent and using effective means of control over the macro- and microstructure in the processes of hardening of the castings and their heat treatment, the strength can be considerably improved. It should be noted that high-chromium cast iron possesses better triboengineering characteristics than steel. Optimization of the entire set of mechanical and technological properties makes it possible to choose the effective grade of the alloy, control the structure of the metallic base depending on the service conditions of the cast part, and use cast iron instead of steel, for example, for drawing or dressing dies. The material of the working parts of the dies should possess a high hardness and wear resistance at a sufficient toughness and an enhanced heat resistance. In order to determine the expediency of the use of high-chromium cast iron as a tool material for pressure treatment of metals we estimated the effect of the content of carbon and chromium and the macro- and microstructure of the metallic base on the heat resistance.