SAE 5160 steel, classified as high-strength, low-alloy steel, is widely used in the automotive sector due to its excellent mechanical strength and ductility. However, its inherently low corrosion resistance limits its broader application. This study explores the application of the cathodic cage plasma deposition (CCPD) technique to enhance the corrosion resistance of SAE 5160 steel. The treatment was performed using a Hastelloy cathodic cage under two atmospheric conditions: hydrogen-rich (75%H₂/25%N₂) and nitrogen-rich (25%H₂/75%N₂). Comprehensive analyses revealed significant improvements in surface properties and corrosion resistance. The hydrogen-rich condition (H25N) facilitated the formation of Cr_0.4Ni_0.6 and CrN phases, associated with a nanocrystalline structure (37.6 nm) and a thicker coating (45.5 μm), resulting in polarization resistance over 290 times greater than that of untreated steel. Conversely, nitrogen-rich treatment (H75N) promoted the formation of Fe₃N and Fe₄N phases, achieving a dense but thinner layer (19.6 μm) with polarization resistance approximately 20 times higher than that of untreated steel. These findings underscore the effectiveness of CCPD as a versatile and scalable surface engineering technique capable of tailoring the properties of SAE 5160 steel for use in highly corrosive environments. This study highlights the critical role of optimizing gas compositions and treatment parameters, offering a foundation for advancing plasma-assisted technologies and alloying strategies. The results provide a valuable framework for developing next-generation corrosion-resistant materials, promoting the longevity and reliability of high-strength steels in demanding industrial applications.

This study investigated the wear resistance of AA1050 aluminum alloy coated using plasma deposition with a vanadium cathode cage and evaluated the effect of subsequently applying a plasma nitriding process to the coated sample. The treatments were carried out at 400°C for 3 hours. To evaluate the composition, thickness and wear resistance of the layers formed, X-ray fluorescence (XRF), scanning electron microscopy (SEM) and fixed ball micro-abrasive wear tests were applied. The treatments altered the wear mechanisms, with the treated samples also showing the two- and three-body wear modes, compared to the aluminium alloy, which only showed the two-body wear mode. The sample coated using only the cathodic cage deposition technique obtained a greater layer thickness (7.6 μm) and better wear resistance, with a reduction of around 83% in the worn volume compared to the 1050 aluminum alloy. However, the subsequent plasma nitriding process proved to be detrimental to the tribological properties of the coating formed, reducing the layer thickness (3.2 μm) and decreasing wear resistance.