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The expanded graphite can be used to make graphite foil or used directly as a "hot top" compound to insulate molten metal in a ladle or red-hot steel ingots and decrease heat loss, or as firestops fitted around a fire door or in sheet metal collars surrounding plastic pipe (during a fire, the graphite expands and chars to resist fire ...
Graphite is characterized by two main groups: natural and synthetic. Synthetic graphite is a high temperature sintered product and is characterized by its high purity of carbon (99.5−99.9%). Primary grade synthetic graphite can approach the good lubricity of quality natural graphite. Natural graphite is derived from mining.
To produce expandable graphite, natural graphite flakes are treated in a bath of acid and oxidizing agent.Usually used oxidizing agents are hydrogen peroxide, potassium permanganate or chromic acid. Concentrated sulphuric acid or nitric acid are usually used as the compound to be incorporated, with the reaction taking place at temperatures of ...
China has unveiled plans to restrict exports of graphite, a mineral used to make steel and batteries for electric vehicles, on national security grounds, the the Ministry of Commerce and the ...
Graphite, named by Abraham Gottlob Werner in 1789, from the Greek γράφειν (graphein, "to draw/write", for its use in pencils) is one of the most common allotropes of carbon. Unlike diamond, graphite is an electrical conductor. Thus, it can be used in, for instance, electrical arc lamp electrodes.
Nuclear graphite is any grade of graphite, usually synthetic graphite, manufactured for use as a moderator or reflector within a nuclear reactor.Graphite is an important material for the construction of both historical and modern nuclear reactors because of its extreme purity and ability to withstand extremely high temperatures.
Graphite may occupy 6 to 10% of the volume of grey iron. Silicon is important for making grey iron as opposed to white cast iron , because silicon is a graphite stabilizing element in cast iron, which means it helps the alloy produce graphite instead of iron carbides ; at 3% silicon almost no carbon is held in chemical form as iron carbide.
GJV at a magnification of 100:1. Compacted graphite iron (CGI), also known as vermicular graphite iron (GJV, VG, [1] JV [2] or GGV from the German: "Gusseisen mit Vermiculargraphit" [3]) especially in non-English speaking countries, [4] is a metal which is gaining popularity in applications that require either greater strength, or lower weight than cast iron.