This paper combines experimental and modelling studies to provide a detailed examination of the influence of porosity volume fraction and morphology on the polarisation-electric field response of ferroelectric materials. The broadening of the electric field distribution and a decrease in the electric field experienced by the ferroelectric ceramic medium due to the presence of low-permittivity pores is examined and its implications on the shape of the hysteresis loop, remnant polarisation and coercive field is discussed. The variation of coercive field with porosity level is seen to be complex and is attributed to two competing mechanisms where at high porosity levels the influence of the broadening of the electric field distribution dominates, while at low porosity levels an increase in the compliance of the matrix is more important. This new approach to understanding these materials enables the seemingly conflicting observations in the existing literature to be clarified and provides an effective approach to interpret the influence of pore fraction and morphology on the polarisation behaviour of ferroelectrics. Such information provides new insights in the interpretation of the physical properties of porous ferroelectric materials to inform future effort in the design of ferroelectric materials for piezoelectric sensor, actuator, energy harvesting, and transducer applications.

本文结合了实验研究和模型研究，详细研究了孔隙率和形态对铁电材料极化电场响应的影响。研究了由于低介电常数孔的存在而使铁电陶瓷介质的电场分布变宽和电场降低，并讨论了其对磁滞回线形状，剩余极化和矫顽场的影响。矫顽场随孔隙率水平的变化被认为是复杂的，并且归因于两种竞争机制，其中在高孔隙率水平下，电场分布展宽的影响占主导地位，而在低孔隙率水平下，基质顺应性增加。更重要。这种理解这些材料的新方法可以澄清现有文献中看似矛盾的观察结果，并提供一种有效的方法来解释孔分数和形态对铁电体极化行为的影响。这些信息为解释多孔铁电材料的物理特性提供了新的见识，为将来在压电传感器，执行器，能量收集和换能器应用的铁电材料设计中的工作提供了信息。