Simulation of nacre with TiN/Pt multilayers and a study of their hardness

TiN/Pt multilayers with individual thicknesses between 1 and 8 nm were prepared by ion beam sputtering deposition to simulate the micro-laminated architecture of nacre. Multilayer hardness and the laminated structure were investigated. It was found that sharp but incoherent interfaces were formed between individual layers. The multilayer hardness had strong dependence on layer arrangement. The range of layer thickness appropriate for high hardness was experimentally determined. Hardness enhancement of 30–70% was generally observed. With the layer thickness properly adjusted, the multilayer can even be harder than the hard component (TiN). Annealing experiments indicated that the hardness enhancement was an intrinsic property of the TiN/Pt multilayers.