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 Iron Castings
Ductile Iron Castings: Since ductile iron was developed in the 1940s, this remarkable metal has proved its value in tens of thousands of engineering and casting applications. Ductile iron is created by an alloying process, which converts the crack-promoting graphite flakes of gray iron into nodules. With this micro-structural transformation, the metal acquires superior ductility, elongation characteristics and machinability. The ductile iron family offers the design engineer a unique combination of strength, wear and fatigue resistance and toughness as well as excellent ductility characteristics. In all its grades, ductile iron exhibits mechanical properties that make it an ideal alloy for investment casting. Tiny amounts of magnesium or cerium are added to these alloys to slow down the growth of graphite precipitates by bonding them to the edges of the graphite planes. Along with careful control of other elements and timings, the carbon separates into spheroidal particles as the material solidifies. Its properties are similar to malleable iron but parts of it can be cast with larger sections.
Iron Castings: Essentially an alloy of iron, carbon (2-4%) and silicon in which the carbon is present in excess of the amount which can be retained in solid solution in austenite at the eutectic temperature. When cast iron contains a specially added element or elements in amounts sufficient to produce a measurable modification of the physical properties of the section under consideration, it is called alloy cast iron. Silicon, manganese, sulfur and phosphorus, as normally obtained from raw materials, are not considered alloy addition. It has a typically lower cost than competing materials and a relatively low cost per unit of strength than other materials. With its wide range of mechanical properties, Iron Casting is suitable for many engineering applications, especially where intricacy of design is required. Iron Casting is commonly used when ductility is not a factor. It is well suited for General Machinery, Stock Fittings, Automotive Parts, Valve Bodies and Railroad Accessories. Iron Casting provides advantages in the areas of Cost, Excellent Machining, Dampening Capacity (ability to absorb vibrations), Good Wear Characteristics (self lubricating) and Compressive Strength.
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