Analysis of mode III cracks in a piezoelectric solid

• Main Author: Wong, Kong Len
• Other Authors: ANG Whye-Teong
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2021
• Subjects: Engineering::Mechanical engineering
• Online Access: https://hdl.handle.net/10356/150202
• Institution: Nanyang Technological University

The usage of piezoelectric materials in our day-to-day applications have been increasingly popular due to technological advancement in our world today. An example would be wearable technologies such as apple watch which uses piezoelectric sensors to track sleeping patterns as well as heart rate. The piezoelectric effect in the piezoelectric material is explained simply where mechanical stress will be produced when the material is subjected to electric current and inversely, electric current will be produced when the material is subjected to mechanical stress. Piezoelectric materials have also been used on applications like transducers, actuators, sensors, generators, motors as well as acoustic devices due to the mechanism behind piezoelectric effect. Therefore, it is important that we study the topic of fracture mechanics in piezoelectric materials to better optimize the designing process of piezoelectric devices to improve the reliability and durability. There has been a surge in the research studies on the topic of cracks in piezoelectric materials over the years. The scope of this project will be geared towards researching about piezoelectric strip embedded with cracks which are assumed to be either electrically permeable or impermeable. To simplify the research of our work, only anti-plane shear stress and in-plane electric static loads will be considered on the piezoelectric strip. By solving the hypersingular integral equations formulated with regards to the problem of interest, we can determine the value of crack opening displacements and jump in electric potential which allows the crack tip stress intensity factor as well as the electric displacement intensity factor to be computed. The project will focus on two mode III collinear cracks and the results will be discussed in the paper.