Study of the mechanical properties of hybrid coating as a function of their structures using nanoindentation

This paper is dedicated to the study of mechanical properties of various organic inorganic coatings in order to investigate the effect of a structural modification. The hybrid material is composed by a mixture of colloidal silica and an organo-silicate precursor whose organic part is a hydride, methyl or phenyl group to obtain simple structural change. These films were prepared by sol-gel process and set down by spin-coating. Mechanical properties such as elastic modulus, hardness, coating fracture energy, interfacial toughness and residual stresses are studied using nanoindentation technique. Relation between structural changes and mechanical properties are studied using solid Si-29 NMR spectroscopy. Three-functional species (T) and tetra-functional species (Q) quantity in the final solid state are discussed in relation to the mechanical properties. (C) 2007 Elsevier B.V. All rights reserved.