The erosive and hydroabrasive wear are very intensive degradation processes of the surface layers of the metallic materials. The wear resistance is influenced by the working conditions and the material parameters like hardness and microstructure. These parameters of the hardfacings are determined by the technology of building-up and the chemical composition of the overlay. The present knowledge of material parameters and their influence on the wear by particles does not allow to predict lifetime of machine parts. Therefore, it is necessary to test candidate materials experimentally. The laboratory tests will enable the optimum selection of the chemical composition of weld deposits and the technology of hard surfacing. The hard deposits containing borides and carbides have improved erosive and hydroabrasive wear resistance. Tribological behaviour of this hard layers have been tested by sand-hydroblast apparatus EO-2 and centrifugal erosion tester CUK-3. The determination of the conditions of optimum application these materials in industry for improving performance and longer service life of various machine parts is the technological aim of our project in the frame of research programme COST 516.