Relation between Structure, Mechanical and Piezoelectric Properties in Cellular Ceramic Auxetic and Honeycomb Structures

Abstract

Optimizing renewable energy harvesting is of major importance in the following decades. In order to increase performance and efficiency, an ideal balance of mechanical and piezoelectric properties must be targeted. For this purpose, the approach of ceramic auxetic and honeycomb structures made of (Ba,Ca)(Zr,Ti)O3 (BCZT) which is produced via injection molding is considered. The main design parameter is the structural angle θ which is varied between −35° and 35°. Its effect on compressive strength, Young's modulus, and Poisson's ratio are determined via uniaxial compression tests and digital image correlation (DIC). Maximum compressive strength of 95 MPa at 0° (porosity of 59%) is found, which is superior to conventional porous ceramics of the same porosity. The piezoelectric constants d33 (max. 296 pC N−1) and g33 (max. 0.068 Vm N−1) are measured via the Berlincourt method and also exceed expectations, regardless of the structure. The theoretical models of Gibson and Ashby (mechanical) and Okazaki (piezoelectrical), as well as finite element method simulations, strengthen and explain the experimental results.

Towards advanced piezoelectric metamaterial design via combined topology and shape optimization

“…The selected samples were fabricated experimentally by ceramic injection moulding of barium titanate (BTO). The basic process for fabricating complex geometric structures has been described in detail in previous work (Biggemann et al, 2018;Köllner et al, 2023;Hoffmann et al, 2023). However, an adaptation of the process flow for complex structures was required.…”

“…Auxetic cellular honeycomb (HC) structures are the most popular auxetic metamaterials, widely studied in the literature due to their relatively simple geometry (Iyer and Venkatesh, 2011;Iyer et al, 2015;Khan et al, 2019). Stress build-up within auxetic HC was verified numerically and experimentally (Whitty et al, 2003) and various configurations of auxetic HC were compared for their superior electromechanical properties towards energy harvesting applications (Köllner et al, 2023). In the last two decades, the role of structural optimization methods, density-based and level set topology optimization in particular (Bendsoe and Sigmund, 2003;Wang et al, 2003), has immensely increased in engineering design.…”

Energy-Reduced Fabrication of Light-Frame Ceramic Honeycombs by Replication of Additive Manufactured Templates

“…With further periodization and homogenization of the cell structure, it has even already been shown that, despite porosities of up to 60%, only a slight reduction in d 33 can occur [25]. We are particularly interested in honeycombs because even increased values could be obtained compared to dense material [12,26]. For this reason, the light-frame honeycombs fabricated here can help to better understand how cellular structures can affect piezoelectric properties, as they are a mixture of different cellular types.…”

Magnetic Control of Vibrational Behavior of Smart FG Sandwich Plates with Honeycomb Core via a Quasi‐3D Plate Theory

“…Other recent published works considering the behavior of FGPMs structures are available in the literature such as refs. [16][17][18][19][20][21][22][23].…”