Tribological systems in hydraulic pumps, motors and cylinders are considerably stressed by friction and wear. Working life of components in hydraulic circuits might be extended by the use of wear resistant materials. Modern processes like Thermal Spray Technology, Physical Vapour Deposition and Plasma Nitration enable the application of wear resistant coatings with excellent friction characteristics. A wide variety of diffe-rent coating materials is available with various proper-ties concerning surface hardness, surface structure and coefficient of friction. Thus, an adaptation of surface properties and loads can be achieved. This paper presents results from investigations of coated simplified specimen and from tests with coated fluid power components.