Properties of PMN-PT Fibre/Epoxy 1-3 Composites for High-Frequency Transducer Applications

摘要

Lead magnesium niobate - lead titanate (PMN-PT) ceramic fibres with a nominal composition of 0.65Pb(Mg_(1/3)Nb_(2/3))O_3-0.35PbTiO_3 were prepared by a modified sol-gel method. The crack-free sintered fibres with 100 μm diameter were embedded in epoxy to form PMN-PT fibre / epoxy 1-3 composites. Composites with 0.13 to 0.33 volume fractions of PMN-PT fibres were fabricated. It was found that the fibre composites have better performance than that of bulk PMN-PT ceramics. The value of k_t is 0.63 for the composite with a fibre volume fraction of 0.2. These composites will be used to fabricate transducers for high-frequency medical ultrasound.