Effect of plasma nitriding temperature on tribological performance and surface integrity of AISI 1045 steel

Abstract

AISI 1045 steel is widely used in mechanical components subjected to wear, where surface performance is critical for service life. This study investigates the effect of plasma nitriding temperature on the tribological behavior and surface integrity of AISI 1045 steel. Samples were nitrided at 400°C and 450°C and characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), Vickers microhardness testing, and micro-abrasive wear tests. The results show that plasma nitriding promotes the formation of Fe 3 N and Fe 4 N phases, leading to a significant increase in surface microhardness compared to the untreated material. Both treatment conditions improved wear resistance, with reduced wear volume and modified wear mechanisms dominated by abrasion and adhesion. Although the sample treated at 450°C exhibited slightly higher hardness, both temperatures resulted in comparable tribological performance. These findings indicate that plasma nitriding at 400°C provides an effective balance between enhanced wear resistance and reduced thermal impact, making it a suitable option for engineering applications where dimensional stability and cost efficiency are required.