Review: Research progress on the impact protection effect of shear thickening materials under dynamic loading

With the continuous advancement of impact protection technology, the development of protective equipment increasingly aims to achieve both high performance and lightweight design. Shear thickening materials possess advantageous properties, including low density, excellent adaptive response, and superior energy absorption capacity, and have been successfully applied in civilian protective gear and military body armor. Consequently, research on the application of these materials in the field of impact protection continues to expand. The two most prevalent types of these materials are shear thickening fluids and shear stiffening gels. Although extensive research exists on both, a comprehensive review that integrates their material mechanisms, mechanical properties, and applications in impact protection remains notably absent. To promote further research on shear thickening materials, this paper presents a systematic and critical review of prior studies. This review first introduces shear thickening fluids and shear stiffening gels—the two mainstream classes of shear thickening materials—and elucidates their respective thickening mechanisms. Subsequently, it summarizes the mechanical properties and influencing factors for both material types under intermediate and high strain rates and presents a consolidated analysis of relevant numerical constitutive models. Building on a thorough understanding of their mechanisms and mechanical performance, this paper then focuses on reviewing the current state of applications for both materials in low-velocity impact protection, ballistic penetration, and blast mitigation. Finally, it concludes by summarizing the limitations of existing research and proposes directions for future research.

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