The Rising of Flexible and Elastic Ceramic Fiber Materials: Fundamental Concept, Design Principle, and Toughening Mechanism

Abstract Traditional ceramic materials are suboptimal for use in complex environments because of their brittleness and sensitivity to flaws. As such, developing flexible and elastic ceramic materials is extremely urgent in frontier domains where high‐frequency vibration or high‐intensity bending environments are inevitable. Fibrillation of ceramic materials is an effective way for the transition of brittleness to flexibility and elasticity, due to its ability to absorb and dissipate stresses through large axial deformations. Here, a comprehensive review of the newly emerging flexible and elastic ceramic fiber materials is presented, starting from an introduction to the fundamental concept, followed by an in‐depth analysis of the relationship between their microstructures and mechanical behaviors, laying emphasis on the toughening mechanism of both individual fibers and fiber assemblies. Finally, current challenges and future development are demonstrated. It is expected that this review may provide meaningful guidance for the advancement of ceramic fiber materials toward better performance and brighter prospects.