Lead magnesium niobate-lead titanate fibres by a modified sol-gel method

Lead magnesium niobate-lead titanate (PMN-PT) ceramic fibres with the nominal composition of 0.65Pb(Mg_1/3Nb_2/3)O₃-0.35PbTiO₃ have been fabricated by a modified sol-gel method. Due to the difficulty of dissolving the magnesium component, the mixed oxide method was used together with the traditional sol-gel method. To obtain crack-free fibres, pyrolysis was carried out at a very slow heating rate under specific atmosphere to control the organic burnout. The thermal and microstructural properties were investigated using thermogravimetric analysis, scanning electron microscopy and X-ray diffraction. The optimum sintering temperature is 1200 °C and yields a fibre with a final diameter of around 100 μm. A single PMN-PT fibre has been poled and its electrical properties were measured. The properties of the fibre are found to be better than that of a ceramic disc.