| With the development of industry, there are many increasing demands to different parts of metal materials, especially to wear resistance and corrosive resistance. However, it is difficult for a kind of material to have high toughness and hardness on actual condition, so compounding casting often is used. Bimetal supports various properties in every part through sound combination between outer-material and inner-material. This paper introduces to use compounding cast processes for making a kind of composite, which is make up of high chrome cast iron and mid-carbon steel, tests the capabilities of interfaces and emphasizes on discussing the compounding-strength, microstructures and mechanics performances. At the same time, with the base of the whole analysis of heat behaviors in the process of bimetal compounding, a reasonable mathematics model is built and used the FEM to calculate temperature field in the process.The chosen outer-material, high chrome casting iron, is of high hardness, wear-resistance and excellent fluidness, and middle carbon steel is a kind of material with good toughness, at the same time , different kinds of heat treats have a little effect on its properties. The volumes' rates between high chrome casting iron and middle carbon steel is an important effect, so it is very necessary to calculate the critical volumes' rates when the casting temperature of high chrome casting iron and middle carbon steel is known. Before casting high chrome casting iron, it is better to coat borax on the middle carbon steel and give middle carbon steel a predicting temperature. But if the high chrome casting iron's casting temperature is too high, some beneficial elements will be damaged. In a result, there is an opportune range of casting temperature.From the research about different processes , we can conclude: the capability of high chrome cast iron and mid-carbon steel's interface is decided by the interface binding strength. These effects can be displayed by the microstructure and values of interface's combinative strengthen and cutting strengthen.From the research of microstructures , we can conclude: overheat which releases from high chrome casting iron is given middle carbon steel. With the optimal parameters, the binding method changes from mechanical binding to metallurgy binding, and it is best to gain a composite layer with the shape of dentation. The main strengthphase of high chrome casting iron is M7C3 carbide, which is discontinuous shape. Thesolidifying direction has two parts: tone is the nearest part of interface, which has random directions of grains because of sharp temperature gradient; another is part far from interface, which has stable temperature gradient.From the research of mechanical properties, we can conclude : decreasing the temperature difference between these two materials is good to gain an excellent interface compounding. The keys of adding interface mechanical properties are to increase high chrome casting iron and middle carbon steel's temperature properly and the volume's rate. But the value is a critical value ,otherwise the grain will grow sharply. Micro- hardness testing dedicates that interface of mechanical binding has brittle phase; cutting strength testing dedicates that increasing volumes' rates will benefit the binding strength of interface, but at the same tine ,the whole tenacious performance will decrease; peeling strength testing dedicated that interface of metallurgy binding is not so easy to have cavities.About the calculation of interface and temperature field, this paper considers the add of heat during the period of bimetal binding .material heat transforming and material phase changing. A model of unstable temperature field and interface temperature is built, what's more, used FEM to analyze and confer.Using C++, a program about calculating interface temperature and temperature field is developed, at the same time OpenGL is used in this program. With the friendly visual windows, this program can realize picture's display.Through...
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