The carbide forming elements are also distributed into matrix and so they have effects on transformation. The wear resistance and the mechanical properties of multi-component white cast iron are affected by not only the type and morphology of eutectic carbide but also the matrix structure varied depending on heat treatment. In order to get instructions of heat treatment endowing the cast iron with desired properties, it is necessary to clarify the transformation behavior of matrix. Here, the continuous cooling transformation behavior of the cast irons containing 5% of each element, Cr, Mo, W, 2% of Co, and 2.0 and 2.8% C were investigated.[10