Ductile iron casting has been used in almost all major industrial sectors. These sectors require high strength, ductility, toughness, wear resistance, resistance to severe thermal and mechanical shocks, high or low temperatures, corrosion resistance and dimensional stability. In order to meet these variations in the conditions of use, ductile iron has many grades that provide a wide range of mechanical and physical properties.
Ductile iron is mainly produced in a non-alloy state. Obviously, this range includes high strength grades with a tensile strength greater than 800 Newtons per square millimeter and an elongation of 2%. The other extreme is a high-resistance grade with an elongation of more than 17% and a correspondingly low intensity (lower 370 N/mm2). Strength and elongation are not the basis for the designer's choice of materials, while other decisive important properties include yield strength, modulus of elasticity, wear and fatigue strength, hardness and impact properties.
The corrosion resistance and oxidation resistance and electromagnetic properties of ductile iron may be critical to the designer. To meet these special uses, a set of austenitic ductile irons, commonly called Ni-Resis ductile iron, was developed. These austenitic ductile irons are mainly alloyed with nickel, chromium and manganese and are listed as international standards.
It is a pearlitic spheroidal graphite cast iron with medium and high strength, medium toughness and plasticity, high comprehensive performance, good wear resistance and vibration damping, and good casting process performance. It can be changed by various heat treatments. Mainly used in various power machinery crankshafts, camshafts, connecting shafts, connecting rods, gears, clutch plates, hydraulic cylinders and other components.