Interface phase transitions and degradation of Pb-free ferroelectric ceramics

Overview

The aging and fatigue (degradation) of oxide ferroelectric materials in service is not understood at a fundamental defect level. In these materials, the thermodynamic state of interfaces such as grain boundaries has not been explored to the extent that it has in non-polar materials. In part, this is because of the multi-physics coupling, and herein lies the key to the richness of the physics.

In this project, we will build on previous work on interfaces in functional oxides and on bulk ferroelectric phase coexistence to develop new multi-physics models. Thermodynamics of bulk phases, interfaces and point defects will be coupled in order to develop understanding of bulk and interface phase transition behaviour in barium titanate and other Pb-free chemistries. This knowledge will enable identification of the origin of ferroelectric degradation and strategies to mitigate this problem.

Eligibility

An ideal candidate would have previous experience in materials modelling, particularly mesoscale modelling, and oxide ceramics. An excellent background in mathematics is required. The student is likely to have an Honours or Masters degree in a discipline such as materials science and engineering, physics or related field. This is part of an international collaboration funded by a the New Zealand Marsden Fund, and excellent communication skills are required. Candidates should satisfy the requirements for admission as a PhD candidate at University of Canterbury.