Conventional piezoelectric ceramics lose their piezoelectric properties near the Curie temperature (Tc), which limits their application at high temperatures. One approach to resolving this issue is to design flexoelectric piezoelectric composites or piezoelectric metamaterials by exploiting the flexoelectric effect of the ferroelectric materials. In this work, an experimental study on two designs of flexoelectric metamaterials is demonstrated. When a ferroelectric ceramic wafer is placed on a metal ring or has a domed shape, which is produced through the diffusion between two pieces of ferroelectric ceramic of different compositions at high temperatures, an apparent piezoelectric response originating from the flexoelectric effect can be measured under a stress. The apparent piezoelectric response of the materials based on the designs can be sustained well above Tc. This study provides an approach to designing materials for high-temperature electromechanical applications.

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Summary The two‐way hollow core precast panel (TWHCPP) exhibits good seismic performance. In this study, the shear behavior of the TWHCPP shear wall with vertical connections was investigated. Specifically, five shear wall specimens, which comprised one cast‐in‐place shear wall, one TWHCPP shear wall without vertical connections, and three TWHCPP shear walls with vertical connections, were investigated experimentally. The TWHCPP shear walls were also modeled through numerical simulation. The experimental and numerical results indicate that the TWHCPP shear wall specimens with vertical connections exhibit monolithic load‐bearing mechanisms before the peak point, which is similar to the cast‐in‐place shear wall specimen. When the peak point of the TWHCPP shear wall specimen was attained, vertical slits were formed in the vertical connection and major vertical crack regions, which divided the shear wall panel into multiple vertical concrete straps. Subsequently, the load‐bearing mechanism of the TWHCPP shear wall transformed to multiple vertical concrete straps working cooperatively with transverse reinforcements. Therefore, the brittle diagonal tension failure mode could be avoided, and a good hysteretic performance could be achieved. The outcomes of this study are expected to provide a useful reference for the application of the TWHCPP shear wall.