- Ferrochrome
Ferrochrome aka. FeCr is a corrosion-resistant alloy of chrome and iron containing between 50% and 65% chrome. It is a finishing material which contains about 50-70% (depending on ore used a the producer)
chromium alloyed withiron . Most of the world's ferrochrome is produced in South Africa, Kazakhstan and India, which have large domestic Cr Ore resources. Increasing amounts coming from Russia and China.Over 80% of the world's ferrochrome is utilised in the production of
stainless steel . Stainless steel depends on chrome for its appearance and its resistance to corrosion. The average chrome content in stainless steel is approximately 18%. It is also used when it is desired to add chromium tocarbon steel . FeCr from Southern Africa know as 'charge chrome' produced from a Cr containing ore with a low Cr content is most commonly used in stainless steel production, where as High Carbon FeCr produced from high grade ore found in Kazakhstan is more commonly used in specialist applications such as engineering steels where a high Cr to Fe ratio and minimum levels of other elements such asSulfur ,Phosphorus andTitanium are important and production of finished metals takes place in small electric arc furnaces compared to large scale blast furnaces.Ferrochrome production is essentially a carbothermic reduction operation taking place at high temperatures. Cr Ore (an oxide of chromium and iron) is reduced by coal and coke to form the iron-chromium alloy. The heat for this reaction can come from several forms, but typically from the electric arc formed between the tips of the electrodes in the bottom of the furnace and the furnace hearth. This arc creates temperatures of about 2800°C. In the process of smelting, huge amounts of electricity are consumed making production in countries with high power charges very costly.
Tapping of the material from the furnace takes place intermittently. When enough smelted ferrochrome has accumulated in the hearth of the furnace, the tap hole is drilled open and a stream of molten metal and slag rushes down a trough into a chill or ladle. The ferrochrome solidifies in large castings, which is crushed for sale or further processed.
Ferrochrome is often classified by the amount of carbon and chrome it contains. The vast majority of FeCr produced is charge chrome from Southern Africa. With high carbon being the second largest segment followed by the smaller sectors of low carbon and intermediate carbon material.
External links
* [http://www.samancorcr.com/ Samancor Chrome]
* [http://www.xstrata.com/ Xstrata]
* [http://www.enrc.com/ ENRC/KazChrome]
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