Alloys ferro-titanium

Ferro-alloys Master alloys containing a significant amount of bon and a few elements more or less soluble in molten bon which improve properties of bon and steels. As additives they give bon and steel better characteristics (increased tensile sbength, wear resistance, corrosion resistance, etc.). For master alloy production carbothermic processes are used for large-scale ferro-sihcon, ferro-chromium, ferro-tungsten, ferro-manganese, ferro-nickel and metallothermic processes (mainly alumino and sihco-thermic) for ferro-titanium, ferro-vanadium, ferro-molybdenum, ferro-boron. 

Stable oxides, such as those of chromium, vanadium and titanium cannot be reduced to the metal by carbon and the production of these metals, which have melting points above 2000 K, would lead to a refractory solid containing carbon. The co-reduction of the oxides with iron oxide leads to the formation of lower melting products, the ferro-alloys, and this process is successfully used in industrial production. Since these metals form such stable oxides and carbides, the process based on carbon reduction in a blast furnace would appear to be unsatisfactory, unless a product saturated with carbon is acceptable. This could not be decarburized by oxygen blowing without significant re-oxidation of the refractory metal. 

The route shown in Fig. 9.12 is one which has been operated commercially in the U.K. on a fairly small scale, quite successfully. As in the case of niobium, it is convenient to use the crude ferro alloy as feed to the chlorination stage. The chloride purification stages lead to pure vanadium trichloride, which is reduced with magnesium in a manner similar to that employed for titanium, zirconium or hafnium. Some of the complexities, applicable in the latter processes owing to the volatile nature of the chlorides, are absent with vanadium. The vanadium metal sponge has some properties in common with the other metal sponges. 

Ferro-Tic, Titanium carbide metal matrix composites, Alloy Technology International, Inc. 

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