PT Journal AU Dobrocky, D Pokorny, Z Studeny, Z Doan, T TI Analyse of Tribological Properties of Layers Created by Plasma Nitriding + DLC SO Manufacturing Technology Journal PY 2018 BP 379 EP 386 VL 18 IS 3 DI 10.21062/ujep/109.2018/a/1213-2489/MT/18/3/379 DE Plasma Nitriding; Layer; DLC; Pin-On-Disc; Friction AB Plasma technology of deposition of thin layers is currently the commonly used technology serving to influence the surface properties of various materials (metals, polymers, ceramics, etc.). The great advantage of applied thin layers is that although they can significantly change the surface properties of coated materials, their advantageous volumetric properties are preserved. The experimental part of work describes the evaluation of the properties of duplex system of the plasma nitrided layer with DLC coating and confronts them with the properties of plasma nitrided layers and polished surfaces. 42CrMo4 and 17Ni4CrMo steels were chosen for experiment. Experimental part deals with the practical analysis of the determination of tribological properties of thin film-substrate (specifically nitrided layer-DLC coating). The tribological properties of selected steels were evaluated using the "Pin on Disc" method. Modified layer formed by duplex system PN+DLC showed up to 8x lower coefficient of friction than nitrided or only polished surface. ER