Production of Al-Ti master alloy by aluminothermic reduction technique

Aluminum-titanium master alloys were prepared with an aluminothermic reduction of titanium dioxide dissolved in cryolite (NaF/AIF(3) = 2.5 molar ratio)-alumina melts in the presence of aluminum. The effects of time, the concentration of the titanium dioxide and temperature were investigated by spectrophotometer, scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques. Al-Ti alloys containing about 7.8 wt% Ti were prepared at T = 1120 degrees C after 10-15 minutes reduction time. The results showed that the reduction reaction occurred very quickly, i.e., within a few minutes. It was found that the reduction product at room temperature was a master alloy composed of an aluminum matrix and a TiAl3 intermediate phase with needle shape. The reduction product was in fact a composite.