From 1906 to 1940, F.M. Becket and his collaborators carried out the process of producing low-carbon ferrochrome from silicon-reduced chromium ore. Tested and produced in 500kW single-phase two-electrode electric furnace (furnace output 400kg) to 12000kW three-phase electric furnace (furnace output 10t) to meet the needs of producing stainless steel. Around 1920, the Swedish Tellur Hertan Ferroalloy Plant developed a three-step process for producing low-carbon ferrochromium. Electric silicon thermal method, also known as Swedish method. In 1939, R. Perrin obtained a patent for the production of low-carbon ferrochromium by using liquid ferrosilicon alloy and chromite-lime melt reaction. Commonly known as the Polun method, also known as the heat exchange method. After continuous improvement, this method has become the main method for producing low-carbon ferrochromium. In 1949 H. Erasmus (H.Erasmus) obtained a vacuum solid-state decarburization method to produce C 0.01% low-carbon ferrochrome patent. Sim-plex Ferrochrome, a low-carbon (low-sulfur) ferrochrome called Simprex, is produced at the Ma-rietta plant of United Carbide Corporation.
