Self‐healing of TiSiN/Ag coatings induced by Ag

Abstract

Ceramic coatings often suffer from the formation and expansion of microcracks, which leads to a failure of the protective function. In this work, we observed self‐healing of the microcracks in the TiSiN/Ag multilayer coating upon heating. This behavior can be attributed to diffusion of the Ag atoms to the cracks in the multilayer coating, while similar cracks in the TiSiN monolayer coating remain unchanged after the same treatment. Furthermore, the TiSiN/Ag coating with healed cracks possesses similar electrochemical corrosion and biofouling properties to the as‐deposited one, suggesting that TiSiN/Ag is a promising system in marine engineering applications. The mechanism of self‐healing was explained by kinetic simulations based on ab initio molecular dynamics and the diffusion activation energies of Ag in irregular ceramic structures have been calculated. The here adopted theoretical method also provides a new pathway for exploring new coating systems with a potential self‐healing function.

Development of robust surfaces for harsh service environments from the perspective of phase formation and transformation

“…Another benefit originating from the Ag diffusion could be the self-healing effect on the cracks generated in the coating system. Zhu et al [72] further studied the self-healing behavior of TiSiN/Ag multilayered coatings upon oxidation using first-principles calculations, molecular dynamics simulations and key experiments. The results suggest that the presence of O 2 induces the oxidation of TiN and Si 3 N 4 phases in the top surface layer and Ag atoms readily diffuse outwards along the phase boundaries between the TiN nanocrystals and the Si 3 N 4 amorphous phase simultaneously [Figure 10A-D], both of which contribute to the self-healing of surface and internal cracks, as well as the maintenance of anti-corrosion and anti-fouling properties.…”

“…The concepts of the materials genome and materials informatics have highlighted that the highly efficient optimization of critical engineering materials (and coatings) requires explicit relationships established between processing, structure and properties. Phase diagrams that can precisely describe the phase [72] with permission from John Wiley & Sons.…”

“…Diffusional behavior of Ag atoms simulated using molecular dynamics for (A) 0, (B) 100, (C) 250 and (D) 400 fs. Figure reproduced from Ref [72]. with permission from John Wiley & Sons.…”

Toward Ceramic Anticorrosion Coatings: A Review

“…(e) the relationship between diffusion coefficient and 1/T; and (f) schematic diagram of the cracks healing. Reprinted with permission from Zhu, et al 184…”