Compacted graphite iron
Encyclopedia
Compacted graphite iron (CGI), also known as vermicular graphite iron (GJV, VG, JV or GGV from the ) especially in non-English speaking countries, is a metal
which is gaining popularity in applications that require either greater strength, or lower weight than cast iron
.
R.D. Schelleng obtained a patent for the production of Compacted graphite iron in 1965.
in compacted graphite iron differs in structure from that in gray iron
because the graphite particles are shorter and thicker. This results in stronger adhesion between the graphite and the iron giving the material a greater tensile strength
.
s.
More recently compacted graphite iron has been used for diesel engine
blocks. It has proven to be useful in the manufacture of V topology diesel engines where the loading on the block is very high between the cylinder banks, and for heavy goods vehicles which use diesel engines with high combustion pressures.
It is also used for turbo housings and exhaust manifolds. In the latter case to reduce corrosion.
Metal
A metal , is an element, compound, or alloy that is a good conductor of both electricity and heat. Metals are usually malleable and shiny, that is they reflect most of incident light...
which is gaining popularity in applications that require either greater strength, or lower weight than cast iron
Cast iron
Cast iron is derived from pig iron, and while it usually refers to gray iron, it also identifies a large group of ferrous alloys which solidify with a eutectic. The color of a fractured surface can be used to identify an alloy. White cast iron is named after its white surface when fractured, due...
.
R.D. Schelleng obtained a patent for the production of Compacted graphite iron in 1965.
Metallurgy
The graphiteGraphite
The mineral graphite is one of the allotropes of carbon. It was named by Abraham Gottlob Werner in 1789 from the Ancient Greek γράφω , "to draw/write", for its use in pencils, where it is commonly called lead . Unlike diamond , graphite is an electrical conductor, a semimetal...
in compacted graphite iron differs in structure from that in gray iron
Gray iron
Gray iron, or grey iron, is a type of cast iron that has a graphitic microstructure. It is named after the gray color of the fracture it forms, which is due to the presence of graphite...
because the graphite particles are shorter and thicker. This results in stronger adhesion between the graphite and the iron giving the material a greater tensile strength
Tensile strength
Ultimate tensile strength , often shortened to tensile strength or ultimate strength, is the maximum stress that a material can withstand while being stretched or pulled before necking, which is when the specimen's cross-section starts to significantly contract...
.
Applications
The first commercial application for compacted graphite iron was for the brake discs for high speed rail trainTrain
A train is a connected series of vehicles for rail transport that move along a track to transport cargo or passengers from one place to another place. The track usually consists of two rails, but might also be a monorail or maglev guideway.Propulsion for the train is provided by a separate...
s.
More recently compacted graphite iron has been used for diesel engine
Diesel engine
A diesel engine is an internal combustion engine that uses the heat of compression to initiate ignition to burn the fuel, which is injected into the combustion chamber...
blocks. It has proven to be useful in the manufacture of V topology diesel engines where the loading on the block is very high between the cylinder banks, and for heavy goods vehicles which use diesel engines with high combustion pressures.
It is also used for turbo housings and exhaust manifolds. In the latter case to reduce corrosion.