GB434400A - Producing niobium alloys - Google Patents

Abstract

Materials containing niobium oxides are reduced with silicon or silicon alloys, such as ferrosilicon, chromium - silicon, ferrochromium-silicon, niobium-silicon, or alloys with other metals unobjectionable in the final product. The amount of silicon in the charge is preferably adjusted to yield an alloy with a niobium to silicon ratio of between about 6 : 1 and 12 : 1, in particular between 7 : 1 and 9 : 1, whereby upwards of 75 per cent of the metal may be recovered and the niobium oxide is selectively reduced in preference to the oxides of tantalum and titanium present. Iron, nickel, chromium or other metals may be added to the product either by reducing in the presence of a metal bath or making the addition during or after the reduction. Slags obtained containing substantial amounts of niobium, tantalum, and titanium may be smelted with enough silicon to yield a niobium-silicon alloy of a less ratio than 6 : 1, this product then being used as reducing agent for niobium oxide-containing material to form the lower silicon alloy.