1 White Iron Castings
White cast iron (white cast iron) containing low levels of silicon, in which the iron carbides formed during solidification of graphite in the matrix bonding. In non-alloy cast iron structure in the form of pearlite.
White cast iron (white cast iron) has a hardness number between 400 and 600 HB with its stress 270 N / mm 2 and still can be improved through a reduction in the carbon content of 2.75 to 2.9%, to 450 N / mm 2. Machining process for white cast iron can only be done by grinding (grinding). White cast iron (white cast iron) used in the manufacture of grinding machine components, completeness crushers, kitchen components heaters (furnaces) and others.
White cast iron is not listed on the british standard. white cast iron (white cast iron) can be given heat treatment (heat treatment) to reduce the number of hardness through the softening process (anealing), ie by heating at a temperature of 8500C to elaborate free-carbon formed by rapid cooling after casting (casting). This process is done only in an emergency. While controlling properties of white cast iron is fixed by cooling control method with “iron chill” as well as the elemental composition of molten material that has been mentioned.
2 Gray Iron Castings
Gray cast iron (gray cast iron) contain elements that shaped graphite flakes that have properties capable machine (machinability) and entered the ranks of British Standards, which distinguish types of gray cast iron is the value of the voltage levels of violence of this cast iron is between 155 HB to HB 320 depending on its level. gray cast iron (gray cast iron) used in the manufacture of crankcases, machine tool bed, brake drums, cylinder head and others.
Gray cast iron (gray cast iron) can be given a heat treatment (heat treatment) to eliminate the voltage after the casting process with “stress reliefing” (see heat treatment process) by heating it slowly between 500oC to 5750C, with a holding time of about 3 hours followed by cooling slowly.
Another process in heat treatment (heat treatment) which allow to do on this gray cast iron is softening (anealing), with this process will be improvement in the structure so that it is possible for rapid machining process, for anealing process is done by heating it at a temperature anealing the 7000c with heating time (holding time) and a half to two hours, which will be formed in a unitary structure enclosed ferrite pearlite matrix, however, the level of violence will be reduced by 240 HB to 180 HB.
3 Iron Castings “Able Wrought”
Able wrought cast iron (cast Malleable Iron) is a type of cast iron that has a white structure, which has a very fine graphite element so carbon element distribution becomes more evenly and easily formed. Able wrought cast iron (cast Malleable Iron) contained in 3 form types, namely: Whitehearth, Blackhearth, and Pearlitic these names are in accordance with the terms microstruktur shape of the cast iron.