SIMULATION OF NACRE WITH TIN PT MULTILAYERS AND A STUDY OF THEIR MECHANICAL-PROPERTIES/

TiN/Pt multilayers with individual layer thickness between 1 and 8 nm have been prepared by ion beam sputtering deposition to simulate the n acreous structure in natural nacre. Both the hardness and toughness we re systematically investigated together with a study of structures of the multilayer. It was found that [111] texture developed during the a lternative deposition of TiN and Pt. The multilayer toughness was high er than that of pure TiN. The hardness was greater than the volume wei ghted mean of the hardness of two components (i.e. TIN and Pt). Both t he multilayer hardness and toughness showed a strong dependence on the individual layer thickness arrangement. When the individual thickness was properly adjusted, the multilayer can even be harder than its har d component (TiN) while the toughness was also greatly improved. Annea ling experiment indicated that such an enhancement was an intrinsic pr operty of the multilayers. Some suggestions for microdesigning of mate rials are thus proposed. (C) 1997 Elsevier Science S.A.