THE GROWTH AND CHARACTERIZATION OF AL AND AL-LI SINGLE-CRYSTALS

Single crystals of pure aluminium (more than 99.8 wt.%) and Al-Li binary alloys containing up to 2.31 wt.% Li were grown using a modified vertical Bridgman method. A technique of making graphite moulds for single-crystal growth of aluminium and Al-Li alloy is reported. By using the graphite mould with a spiral crystal selector, single crystals of aluminium and Al-Li alloy in the form of rods 15 mm in diameter were grown successfully. The lithium loss and dislocation density of these single crystals were much lower than those of crystals grown with an Al2O3 or ZrSiO4 mould.