Investigations on the liquid phase in barium titanate ceramics with CuO additives

CuO is a very interesting material in the field of microwave sintering beca use it can act as an internal susceptor in BaTiO3 ceramics. We examined pow der tips of CuO in contact with BaTiO3 green bodies by heating microscopy. The results show that the formed liquid phase cannot dissolve BaTiO3, at le ast in the examined temperature range up to 1140 degreesC. This melt is cre ated at about 1130 degreesC. Additional differential thermo analysis/thermo gravimetry investigations revealed that at first all the CuO is converted t o Cu2O. Then only a part of the created CuO is retransformed into CuO. A li quid phase is formed from CuO and Cu2O, but not with the eutectic compositi on.