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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.
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Spray Pyrolysis‐Aerosol Deposition for the Production of Thick Yttria‐Stabilized Zirconia Coatings
Aerosol deposition (AD) is a coating technique wherein particles are impacted onto a target substrate at reduced pressures, and supersonic particle impact velocities lead to coating consolidation. The limiting step in AD application is often not supersonic deposition operation, but aerosolization of powder particles with the proper size distribution; the translational impact velocity is strongly size‐dependent. It is demonstrated that by directly synthesizing particles in the gas phase, size‐controlled ceramic particles can be injected into AD systems. This in situ formation step obviates the need for particle aerosolization. Ultrasonic spray pyrolysis (USP) is applied to produce yttria‐stabilized zirconia (YSZ), and USP is directly coupled with AD to produce consolidated, thick, YSZ coatings on metal substrates. USP‐AD yields YSZ coatings on stainless steel and aluminum substrates with porosities <0.20, which grow to thicknesses beyond 100 μm. Aerodynamic particle spectrometry and electron microscopy reveal that the depositing particles are 200 nm–1.2 μm in diameter, though each particle is composed of nanocrystalline YSZ. Supporting computational fluid dynamics calculations demonstrate that the YSZ particle impact speeds are above 300 m s−1. Thermal conductivity measurements demonstrate that USP‐AD coatings have conductivities consistent with those produced from high‐temperature processes.
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- Award ID(s):
- 1420013
- PAR ID:
- 10225954
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Engineering Materials
- Volume:
- 23
- Issue:
- 8
- ISSN:
- 1438-1656
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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