Converse Transduction in the Presence of Strong Electrical Field Gradients in Ferroelectrics (ConTraGrad)

• Applicants: Professor Dr.-Ing. Marc Kamlah; Professor Dr.-Ing. Norbert Schwesinger
• Subject Area: Microsystems ; Electronic Semiconductors, Components and Circuits, Integrated Systems, Sensor Technology, Theoretical Electrical Engineering ; Synthesis and Properties of Functional Materials
• Term: from 2018 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 391065131

• Final Report Year: 2024

Final Report Abstract

The overall objective of this project is gaining a deeper insight into the behavior of the ferroelectric class of piezoelectric materials when subjected to high electric fields and strong electrical gradients covering both, the piezoelectric and flexoelectric effects. The scientific goal of the modelling activities in this project was to simulate the influence of the flexoelectric effect on the deformation behaviour of actuators with single-sided interdigital electrode (IDE) structures and possibly other technical systems where flexoelectricity can play a crucial role in the system response. As a first step, a phenomenological macroscopic material model covering all relevant coupled electromechanical hysteresis properties of ferroelectric ceramics has to be implemented in an efficient finite element code. By simulating IDE model systems with purely piezoelectric and ferroelectric responses, neglecting the flexoelectric properties, a starting point for quantifying the influence of flexoelectricity is established. In this step, particular focus is directed on understanding and optimizing the deformation of the actuator after poling and investigating its potential for actuation. An essential work package is the development of a macroscopic continuum model including for the first time flexoelectricity in addition to ferroelectric large-signal hysteresis behavior. With this model, the ability is created to simulate the interplay of flexoelectricity and poling induced piezoelectricity in ferroelectric materials. The view inside the device allows a deeper understanding of this expected complex coupling of these effects and the influence on the macroscopic behaviour of microelectromechanical systems (MEMS). With respect to the IDE systems, the goal is to understand the relevance of the inverse flexoelectric effect and its contribution to a possible material actuation.

Publications

• An isogeometric approach to flexoelectric effect in ferroelectric materials. International Journal of Solids and Structures, 162, 198-210.
  Liu, Chang; Wang, Jie; Xu, Gang; Kamlah, Marc & Zhang, Tong-Yi
  
• Stroboscopic Video Microscopy for In-Plane Motion Measurements Up to 2 MHz with Picometer Resolution. 2021 IEEE 34th International Conference on Micro Electro Mechanical Systems (MEMS), 1040-1043. IEEE.
  Voss, Andrej; Seyfert, Lars & Hemmert, Werner
  
• “Ferroelectric Ceramics for Actuator and Sensor Applications: Finite-Element-Modeling of Lead- Free Composites and Electrode ConFigureations.”, MSE/P3T1 seminar series Functionality by Information-guided Design, Karlsruhe Institute of Technology (December 2021)
  F. Streich, F. Sutter, K.G. Webber, A. Martin, N. Schwesinger, L. Seyfert & M. Kamlah
  
• A variational framework for microscopically motivated modeling of ferroelectric materials.”, 5th African Conference on Computational Mechanics, Cape Town, South Africa (November 2022)
  F. Sutter & M. Kamlah
  
• Contribution of converse flexoelectric effect in PZT ceramics in presence of strong electrical fields. Active and Passive Smart Structures and Integrated Systems XVI, 42. SPIE.
  Seyfert, Lars; Schwesinger, Norbert; Voss, Andrej & Hemmert, Werner
  
• Stroboscopic video microscopy with sub-nanometer accuracy for characterizing and monitoring MEMS. Nondestructive Characterization and Monitoring of Advanced Materials, Aerospace, Civil Infrastructure, and Transportation XVI, 49. SPIE.
  Voss, Andrej; Seyfert, Lars; Schwesinger, Norbert & Hemmert, Werner
  
• “Finite Element Analysis of the Nonlinear Material Behavior of Ferroelectrics Under Complex Load Scenarios.”, ASME Conference on Smart Materials, Adaptive Structures, and Intelligent Systems, Dearborn, Michigan, USA (September 2022)
  F. Sutter & M. Kamlah
  
• “Thermodynamically consistent and microscopically motivated modeling of ferroelectric materials within a variational framework.”, 11th European Solid Mechanics Conference, Galway, Ireland (July 2022)
  F. Sutter & M. Kamlah
  
• “Variational modeling of ferroelectric materials in a microscopically motivated framework.”, 9th GACM Colloquium on Computational Mechanics, Essen, Germany (September 2022)
  F. Sutter & M. Kamlah
  
• Variational free energy based macroscopical modeling of ferroelectroelasticity. Journal of the Mechanics and Physics of Solids, 178, 105341.
  Sutter, Felix & Kamlah, Marc
  
• “Materiell nichtlineare Kontinuumsmodellierung ferroelektrischer Funktionskera miken mit piezoelektrischen und flexoelektrischen Eigenschaften.”, Dissertation, Karlsruhe Institute of Technology (KIT), 2023,
  F. Sutter
  
• “Microscopically motivated continuum modeling of domain switching effects in ferroelectrics.”, 2023 Spring Meeting of the European Materials Research Society (E-MRS), Strasbourg, France (May 2023)
  F. Sutter & M. Kamlah
  
• “On the continuum modeling of flexoelectricity in ferroelectric materials.”, 10th GACM Colloquium on Computational Mechanics, Vienna, Austria (September 2023)
  F. Sutter & M. Kamlah