<p>The objective of this experimental study is to investigate the mechanical, tribological, and electrochemical behavior of chromium nitridelayers deposited on 42CD4 and XC42 steels surfaces using the DC reactive magnetron sputtering method. Prior to the coating process, all samples annealed have been quenched and tempered. The chromium nitride thin films were deposited using a nitrogen/argon gas mixture. A comparative analysis was carried out to assess the influence of the chemical composition of steels, in particular chromium and molybdenum, on the properties of chromium nitride coatings. Various experimental techniques were employed, including x-ray diffraction, scanning electron microscopy, atomic force microscopy, nanoindentation, scratch testing, and electrochemical testing. x-ray diffraction results revealed that the coatings are composed of Cr, CrN and Cr₂N phases. Hardnesses were improved for 42CD4 steel, from 3.24 GPa in the quenched and tempered condition to 11 GPa in the coated condition, and from 3.17 GPa after quenching and tempering to 9 GPa for coated XC42 steel.Scratch testing demonstrated that a progressively applied normal load of 50 N provided better adhesion on 42CD4 steel (39N) compared to XC42 steel (21.8 N). Tribological tests indicated that the 42CD4/CrN system exhibited a lower friction coefficient (<i>µ</i> = 0.48) compared to the XC42/CrN system (<i>µ</i> = 0.55). Corrosion resistance is improved by 89.21% for coated 42CD4 steel, and 87.57% for coated XC42 steel.</p>