5824.4:
Search for Characteristic Dimension of Roughness (CDR)
Abstract
This study shall discover the limits of existing physico-chemical laws for adhesion and wetting phenomena by a systematic tailoring and throughout characterization of nano-structured and specifically coated surfaces. Wetting and friction are strongly influenced by the chemical composition of the top layer and by the roughness of the substrate. The project aims to determine theoretically and experimentally the influence of a dominating parameter, the characteristic dimension of roughness (CDR), influencing wetting and friction properties. The CDR includes the roughness of a surface containing the autocorrelation function of the topology, the absolute size of the obstacles, and its geometry.
The proposed comprehensive study clarifies the function of chemical composition and topology with respect to adhesion properties of real surfaces. Self-cleaning and liquid repellent surface finishing processes of inorganic oxides and polymers are developed resulting from the determination of the characteristic dimension of the surface. The long term objectives of the project are:
· decrease of energy consumption,
· decrease of pollution,
· decrease of costs of health care.