| 摘要 |
<p>Titanium-rich alloys free from iron are produced from raw materials such as bauxite, rutile or ilmenite by calcining the raw material in a rotary kiln, multiple hearth furnace or the like with or without the addition of carbon, melting the resulting material with cryolite at a temperature of about 1000 DEG C. whereby titanium is dissolved in the cryolite and separated from iron, then reducing the titanic acid contained in the cryolite in another furnace at about 1000 DEG C. with excess aluminium which is added in the form of chips, scrap, or waste, the metallic titanium collecting with the excess aluminium as an alloy at the bottom of the furnace. The reduction is preferably carried out in an induction furnace utilizing the electromagnetic stirring effect of the furnace. Where the raw material contains silica the silica remains dissolved in the cryolite during the reduction. The titanium-aluminium alloy may be further enriched by subjecting it to a liquation at about 1000 DEG C. to recover titanium in the form of Al3Ti containing 37.2 per cent of titanium. Aluminium may be recovered from the cryolite bath by electrolysis.</p> |
