During their applications, ferroelectric devices are subjected not only to electromechanical loading but also to thermal fields, inducing additional stresses and impairing their functionality. Additionally, internal heat generation can occur by the dissipation of the inelastic work resulting from ferroelectric hysteresis. Moreover, at extreme electromechanical field concentrations like cracks, ferroelectric devices may fail by brittle fracture or fatigue. In the present study, the thermal effects on the fracture behavior of ferroelectric ceramics are investigated. The well-established micromechanical material model for ferroelectric domain switching is enhanced to represent the fully coupled thermo-electro-mechanical behavior. The coupling considers the pyroelectric and thermal strains effects. The internal heat production, which leads to transient temperature fields, is taken into account, as well as the temperature dependency of material parameters. The thermo-electro-mechanical fields at the crack tip are analyzed using a boundary layer approach for small-scale switching conditions. A fully transient heat conduction problem is considered, emphasizing the effect of the driving frequencies on heat generation. The configurational forces concept combined with the thermo-electro-mechanical extension of the J-integral are used to analyze the impact of the different factors on the crack driving energy.

在应用过程中，铁电器件不仅要承受机电负载，还要承受热场，从而产生额外的应力并损害其功能。此外，铁电磁滞引起的非弹性功的耗散会导致内部发热。此外，在裂纹等极端机电场集中情况下，铁电设备可能会因脆性断裂或疲劳而失效。在本研究中，研究了热对铁电陶瓷断裂行为的影响。用于铁电畴切换的完善的微机械材料模型得到增强，以表示完全耦合的热机电行为。耦合考虑了热电和热应变效应。内部产热，这会导致瞬态温度场，以及材料参数的温度依赖性。裂纹尖端的热机电场使用边界层方法在小尺度切换条件下进行分析。考虑了一个完全瞬态的热传导问题，强调了驱动频率对发热的影响。构型力概念与热机电扩展相结合J-积分用于分析不同因素对裂纹驱动能的影响。