In this paper, the development of multicomponent white cast iron as a new material for work rolls of hot finishing stands are described based on research from the view points of alloy design, solidification structure, solidification sequence, phase diagram, phase transformation behavior and heat treatment characteristics. As a result, the solidification structure, particularly type and morphology of eutectic carbides, can be controlled by combining alloying elements. Phase transformation behavior obtained from continuous cooling curves provide useful instructions for the heat treatment process. Hardness and retained austenite in the matrix could be widely controlled, and remarkable secondary hardening due to precipitation of special carbides was found to make the matrix hard and strong enough for practical use. The excellent performance of hot work rolls made of multicomponent white cast iron is very popular in Japan. This performance reputation has spread worldwide. Finally, multicomponent white cast iron will be used in other applications as wear-resistant materials, especially in cold working mill rolls.
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