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This research concerns the development and the characterization of new materials with low friction, high compressive strength and improved wear resistance for application in civil engineering (e.g. sliding elements in structural bearings and isolation systems), in bioengineering (e.g. articular surfaces in joint prostheses), mechanical engineering (e.g. sliding bearings and guides), and so on. The two main aims are: (a) the development of processes for manufacturing new sliding materials with improved tribological and endurance properties, and (b) the determination of the friction–pressure– velocity and wear–sliding path characteristics of the new materials in order to create consistent databases that could be used for the design of better performing sliding devices and components. In the continuation of the research program, computer simulations are planned of the mechanical response of structural elements made of these innovative materials. The research project was partly funded by contracts with companies operating in the field of bridge bearings and isolation devices. (a) Development of new sliding materials Polymers with low friction characteristics are already known and widely used in many engineering applications (e.g. PTFE, UHMWPE, PA, etc.); however these polymers usually exhibit poor or moderate resistance to wear and/or degradation of properties with ageing and oxidation. A new process, consisting of irradiation with electron beam and subsequent thermal stabilization, has been designed and developed within the present research. The process allows the properties of the base polymers to be enhanced, the resulting materials exhibit the same low friction as the parents, but higher compressive strength and increased resistance to wear and to viscous flow. (b) Characterisation of tribological properties The mechanical and frictional properties of the new materials have been investigated in order to determine their suitability to applications in sliding bearings for civil engineering works and in articular joint prostheses. The resistance to chemical agents and to oxidation is assessed by means of tests of chemical compatibility and accelerated ageing. The compressive strength is evaluated by means of creep tests at different temperatures and both the maximum load bearing capacity and the cold flow properties are assessed. The friction properties are evaluated by means of two sets of experiments: the first set includes short term tests performed at ambient temperature under different combinations of contact pressure and sliding velocity, and the second set includes constant velocity tests run at different temperatures, down to – 50°C and up to +40°C, to determine the friction performance of the sliding materials at normal, low and very low temperature. An analytical model of the pressure-friction-velocity characteristics has been also developed. Finally the wear performance is assessed by means of a long term test up to 50,000 m sliding distance. At present new materials developed within the research are in use as sliding polymers in bridge bearings and in isolation devices (friction pendulum) (about 100 tons of materials already installed), and application of an enhanced crosslinked UHMWPE for knee prostheses is in progress.