A significant imperfection of parts made from linear blockpolyurethanes under conditions of friction contact in the presence of water medium is an intensification of hydrolysis processes and reduction of bulk strength. In order to slow down the hydrolysis process, samples of the polyurethanes were subjected to three types of thermal impacts: thermal processing during some time, infrared and laser irradiations. It has been established that processing in thermal fields of different intensity allows 5-10 times increase of wear resistance of these materials during friction in water medium.