ПРОГРЕССИВНЫЕ ТЕХНОЛОГИИ В МАШИНОСТРОЕНИИ THE ADVANCED TECHNOLOGIES IN MECHANICAL ENGINEERING P. Wach, J. Tacikowski, J. Michalski, M. Betiuk, K. Burdyński, L.Kwiatkowski CORROSION RESISTANCE AND TRIBOLOGICAL PROPERTIES OF DUPLEX LAYER The paper presents results of research on gas nitriding and PA PVD-Arc technologies to form duplex layer on constructional and hot work tool steels. <...> As a result a two layer structure of nitrided layer and CrN coating was obtained. <...> Authors shown results of investigations of duplex layer: hardness, microstructures, wear and corrosion resistance. <...> The steel after nitriding consists of a white layer of about 2-15 µm or without it (only diffusion layer about 150-400 µm). <...> In the case of anticorrosion nitrided layer, oxidation and impregnation can be replaced by using CrN coats Key words: duplex layer, PVD, nitriding, corrosion and wear resistance 1. <...> INTRODUCTION A wear resistant layer produced by PAPVD method case when the surface does not contain nitrides as a deposit of these compounds, there is only a diffusion layer, Fe(N). <...> Many authors claim that the formation a Fe(N) phase is necessary to obtain a good adhesion of PVD coat to nitride surface, while the white layer is undesirable [1, 2 and 4]. <...> In this paper formation of a complex (nitrided layer/PVD coat) onto X38CrMoV5-1 and 4140 steel is presented. <...> It is described in the professional literature that properties of a deposit are determined by the properties of a structure obtained by gas nitriding process. <...> A nitride layers contain a mixture of iron nitrides such ε-Fe2-3 and γ`-Fe4 N N, so-called white layer (WL) [3]. <...> In the PVD-arc method onto X38CrMoV5-1, 4140 steels after gas nitriding process (controlled gas nitriding – Nitrex) – duplex process. <...> The influence of diffusion nitrided layer structure (controlled gas nitriding) and influence of application a thin coat from Cr-N diagram (PVD-Arc) on corrosion and wear resistance of deposited system are presented in this paper. <...> EXPERIMENTAL Duplex layer were produced on hot work tool steel – and constructional steel 4140. <...> The chemical composition of X38CrMoV5-1 and 4140 steel is given in Table 1. <...> The wear <...>