The thermo-mechanical breakdown of ferroelectric ceramics

It is demonstrated that brittle fracture plays an important role in the breakdown process of ferroelectric ceramics. Mechanical fracture and dielectric failure are recognized to be microstructure sensitive, and both of these have been shown to depend upon intrinsic-extrinsic microstructure parameters and the heat diffusion condition. The toughening-strengthening effect of dispersed ZrO₂ particles caused by t→m martensitic transformation, which leads to crack branching and crack closing in the breakdown process, is a reasonable compromise for improving fractural strength and modified electronic properties. A thermomechanical breakdown is proposed which can replace the typical thermal breakdown mechanism of brittle electrical ceramics with lower thermal conductivity