FERROTITANIUMA master alloy of titanium with iron used as a purifying agent for irons and steel owing to the great affinity of titanium for oxygen and nitrogen at temperatures above 1472°F (800°C). The value of the alloy is as a cleanser, and little or no titanium remains in the steel unless the percentage is gaged to leave a residue. The ferrocarbon titanium is made from ilmenite in the electric furnace, and the carbon-free alloy is made by reduction of the ore with aluminum. Ferrotitanium comes in lumps, crushed, or screened. High-carbon ferrotitanium has 17% titanium and 7 carbon. It is used for ladle additions for cleansing steel. Low-carbon ferrotitanium has 20 to 25% titanium, 0.10 carbon, 4 silicon, and 3.5 aluminum. It is used as a deoxidizer and as a carbide stabilizer in high-chromium steels. Graphidox has 10% titanium, 50 silicon, and 6 calcium. It improves the fluidity of steel, increases machinability, and adds a small amount of titanium to increase the yield strength. The Grainal alloys, for controlling alloy steels, have various compositions. Grade No. 6 has 20% titanium, 13 vanadium, 12 aluminum, and 0.20 boron. Tam alloy No. 78 contains 15 to 18% titanium, 7 to 8 carbon, with low silicon and aluminum. It is used in cast iron and steels. Tam alloy No. 35 has 18 to 21% titanium and only 3.5 to 4.5 carbon. Its melting point is 2750°F (1510°C). Ferrotitaniums with 18 to 22% titanium are used for making fine-grained forging steels. Carbotam contains 16 to 17% titanium, 2.5 to 3 silicon, 6.5 to 7.5 carbon, 1.5 to 2 boron, and less than 1 calcium. It is used for
cast steels to contain boron for high hardness. Manganese titanium is used as a deoxidizer for high-grade steels and for nonfer-rous alloys. A common grade contains 38% manganese, 29 titanium, 8 aluminum, 3 silicon, 22 iron, and no carbon. Nickel titanium is used for hard nonferrous alloys. The low-iron grade contains 15% titanium, 5 aluminum, 4 silicon, 1 iron, and 75 nickel. Thermocol is a ferrocolumbium for adding columbium to steel. It contains 53% columbium and 0.15 maximum carbon. It has an exothermic reaction which prevents chilling of the molten metal.
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