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Abstract Routine high strain rate impacts from the surrounding environment can cause surface erosion, abrasion, and even catastrophic failure to many structural materials. It is thus highly desirable to develop lightweight, thin, and tough impact resistant coatings. Here, inspired by the structurally robust impact surface of the dactyl club of the peacock mantis shrimp, a silicon carbide and chitosan nanocomposite coating is developed to evaluate its impact resistance as a function of particle loading. High strain rate impact tests demonstrate that coatings with 50% and 60% SiC have optimal performance with the greatest reduction in penetration depth and damage area to the substrate. Post‐impact analysis confirms that these concentrations achieve a balance between stiffness and matrix phase continuity, efficiently dissipating impact energy while maintaining coating integrity. The addition of SiC particles helps dissipate impact energy via interphase effects, particle percolation, and frictional losses due to particle jamming. The formation of these stress paths is also modeled to better understand how the addition of particles improves coating stiffness and the stress distribution as a function of particle loading. These findings highlight the potential of bioinspired materials and their promise to promote innovation and breakthroughs in the development of resilient multifunctional materials. 

The rising interest in 3D-printing of concrete structures for use in marine environments requires development of concrete mixtures with adequate mechanical and durability characteristics. The incorporation of alternative cementitious materials, combined with careful selection of printing parameters has emerged as an effective way of controlling not only the fresh properties and printability of mixtures, but also their mechanical and durability properties. This paper presents the results of various durability related tests performed on 3D-printed mortars, including density, porosity, rate of water absorption and resistance to chloride penetration. Results of these tests indicate that the performance of mortar elements 3D-printed using controlled overlap process was similar to the performance of conventionally cast mortar elements with the same composition. Moreover, the results of the chloride transport related tests obtained from all specimens evaluated during the course of the study indicate low chloride ion penetrability, thus re-affirming that combination of the proposed material and 3D-printing method of fabrication have a potential for producing structural elements for applications in marine environments.