Elastic modulus, indentation pressure and fracture toughness of hybrid coatings on glass

The indentation load-displacement behavior of an organic-inorganic hybrid coating was tested using a Berkovich indenter in an attempt to offer a simple and fast method to analyze the mechanical properties of a coating. The coatings were deposited using a spin-coating technique. The elastic modulus and the indentation pressure as a measure of the hardness were determined on the basis of the load-displacement curve. The effects of the coating thickness and the coating preparation conditions were investigated. Cracks, delamination and chipping were observed and were used to assess the fracture toughness of the coating and the interface. Elastic modulus, indentation pressure and the fracture toughness were dependent on the time elapsed before application of the coating fluid and on the curing temperature.