PIEZOELECTRIC COMPOSITES WITH SOFT ELASTOMER INCLUSIONS FOR BIOMEDICAL IMAGING APPLICATIONS
Christian Della1, Kasem Chaisieng1, Dong Wei Shu2
1University of Glasgow Singapore, Singapore;
2Nanyang Technological University, Singapore
1-3 piezoelectric composites or “piezocomposites” have been widely studied due to their practical applications in biomedical imaging and ultrasound therapy. The piezocomposite consists of a piezoelectric fibre and a polymer matrix. The long and thin fibres that are made of piezoelectric ceramics and are embedded in the piezoelectric or non-piezoelectric polymer matrix, which gives piezocomposites the flexibility to conform to curved surfaces. A major advantage of using piezocomposite materials over the conventional monolithic piezoelectric ceramic is its ability to be tailored for specific applications, particularly its electromechanical properties and figures of merit.
Previous analytical studies showed that the performance of the piezocomposite can be enhanced for biomedical imaging applications by adding porosity in the matrix of the piezocomposite. However, it can be a challenge to manufacture the piezocomposite with the suggested porosity orientation. In this research work, a soft inclusion is used as a substitute for the porosity. By using a two-step micromechanics model, the results of the study showed that the performance of the piezocomposite with soft inclusions in the matrix is comparable to that of the piezocomposite with porosity in the matrix. The performances of various piezocomposites with new relaxor ferroelectric materials, such as PMN-PT and PZN-PT, as fibre materials in the composite are also studied.