Characterization of lead-based relaxor ferroelectric ceramics sintered in a 2.45 GHz microwave radiation

Microwave processing of xPb(Mg1/3Nb2/3)O-3-yPb(Zn1/3Nb2/3)O-3-zPbTiO(3) relaxor ferroelectric ceramics was investigated in a 2.45 GHz multimode cavity. The microwave-sintered samples were densified more rapidly and in a shorter time than the conventional sintered sample. A much smaller grain size and more uniform microstructure was developed in microwave heating. Dielectric measurement showed microwave sintered samples could obtain comparable dielectric properties (high pemittivity of 20,000) to the conventional. It was found that a high breakdown strength of 10 kV/mm and mechanical strength of 90 MPa can be achieved by the microwave method. It shows the potential to improve the figure of merit for the materials. The results reveal that microwave processing is a promising method for sintering the high dielectric ceramics. (C) 2000 Kluwer Academic Publishers.