Optimization of 1-3 relaxor-PT single-crystal/polymer composites

PZN-PT single crystals exhibit an ultra-large longitudinal bar mode coupling coefficient (k33) of approximately 0.94. The thickness mode coupling coefficient (kt), however, is just comparable to soft PZT ceramics. In order to utilize the advantages of single crystals, it is desirable to incorporate them into a 1 - 3 composite structure. The single crystals possess a very large effective radial mode-coupling coefficient (kp) and are elastically soft compared with PZT ceramics. As a result, 1 - 3 single crystal polymer composites exhibit a very large kp of approximately 0.7 and only moderately enhanced kt (approximately 0.8) when typical epoxies are used as the matrix material.