Ductile iron castings have been used in almost all major industrial sectors, which require high strength, plasticity, toughness, wear resistance, heat resistance and mechanical impact resistance, high and low temperature resistance, corrosion resistance and dimensional stability. In order to meet these changes in service conditions, there are many grades of ductile iron, which provide a wide range of mechanical and physical properties.
According to ISO 1083, most ductile iron castings are mainly produced in non-alloy state. Obviously, this range includes high strength grades with tensile strength greater than 800 N/mm2 and elongation of 2%. At the other extreme, it is a high plastic grade, with elongation greater than 17% and corresponding low strength (the lowest is 370 N/mm2). Strength and elongation are not the only basis for designers to choose materials. Other decisive and important properties include yield strength, elastic modulus, wear resistance and fatigue strength, hardness and impact properties. In addition, corrosion resistance, oxidation resistance and electromagnetic performance may be the key for designers. In order to meet these special purposes, a group of austenitic ductile iron, usually called nickel-resistant ductile iron, has been developed. These austenitic nodular cast irons are mainly alloyed with nickel, chromium and manganese and are listed in international standards.
It is pearlescent ductile iron with medium and high strength, medium toughness and plasticity, high comprehensive performance, good wear resistance and vibration reduction performance and good casting process performance. Its properties can be changed by various heat treatments. Mainly used for crankshaft, camshaft, connecting shaft, connecting rod, gear, clutch plate, hydraulic cylinder and other parts of various power machinery.