Performance evaluation of AlB12 and AlB2 for the boron treatment of molten aluminium

Aluminium has been used as an alternative to copper for power transmission. However, the presence of impurities especially transition metals deteriorate the electrical conductivity of smelter grade aluminium [1]. Transition metal impurities such as titanium (Ti), zirconium (Zr), vanadium (V) and chromium (Cr) are removed from molten aluminium by the addition of Al-B master alloys, called boron treatment[2-6]. Al-B master alloys contain AlB12/AlB2 phases that provide boron to form transition metal borides during the boron treatment process. Transition metal borides formed are heavy that settled at the bottom of the furnace during holding of molten aluminium. Thereafter, relatively pure aluminium is decanted from the top of the holding furnace. The boron treated aluminium is used for the manufacturing of electrical conductors.