한국주조공학회

In this study, the effects of the pouring temperature, preheating temperature, surface c condition and fraction of the wear resistant part on the production of duo-castings were investigated using a high Cr white cast iron w with excellent abrasion resistance and a low Cr alloy steel with good toughness. The constituent materials of the duo-castings were des designed to have high hardness, fracture toughness and abrasive wear resistance for the replacement of high Mn alloy steels with low ab abrasive wear resistance. In particular, the amount of abrasive wear of 17% Cr white cast iron was about 1/20 of that of high Mn alloy s steel. There was an intermediate area of about 3mm due to local melting at the bonding interface of the duo-castings. These intermediate re regions were different from those of the constituent materials in chemical composition and microstructure. This region led to fracture w within the wear resistant part rather than at the bonding interface in the bending strength test. The bending fracture strengths were 516-824 MPa, which were equivalent to the bending proof strength of high Mn steel. The effects of various casting conditions on the duo-cast behavior were studied by simple pouring of low Cr alloy steel melt, but the results proved practically impossible to manufacture duo-castings with a sound bonding interface. However, the external heating method was suitable for the production of duo-castings with a sound bonding interface.

Duo-castings, Wear resistance, High-Cr white cast iron, Preheating and Pouring temperatures, Composite fraction