On the Crystallization of Terbium Aluminium Garnet

Attempts to grow terbium aluminium garnet (Tb₃Al₅O₁₂, TAG) by the CZOCHRALSKI method lead to crystals of millimeter scale. Larger crystals could not be obtained. DTA measurements within the binary system showed that TAG melts incongruently at 1840°C. The perovskite (TbAlO₃, TAP) with a congruent melting point of 1930°C is the most stable phase in this system. The region for primary crystallization of TAP covers the chemical composition of TAG and suppresses the primary crystallization of the terbium aluminium garnet.