| Abstract |
| Wear resistance and fracture toughness of heat-treated duo-cast materials composed of a high-chromium white cast iron and a low-chromium steel were investigated in this study. Different size, volume fraction, and distribution of M7C3 carbides were employed to the wear resistant part by changing the amount of chromium and molybdenum, and the volume fraction of martensite in the austenitic matrix was varied by the heat treatment. In the alloys containing a small amount of chromium, a network structure of eutectic M_(7)C₃carbides was formed along solidification cell boundaries, and led to the improvement of wear resistance and fracture toughness. After the heat-treatment, the selective wear of the matrix and the cracking or fallen-offs of carbides were considerably reduced since the hardness difference between carbides and matrix decreased by the increase in the matrix hardness, thereby leading to the improvement of the wear resistance. However, the fracture toughness of the heat-treated alloys was lower than that of the as-cast alloys because the matrix containing a considerable amount of martensite did not prevent effectively the crack propagation. (Received July 20, 2004) |
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| Key Words |
| Duo-cast alloys, Wear resistance, Fracture toughness, High-chromium white cast iron |
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