Microstructure and mechanical properties of AISI 321 steel irradiated with high-intensity nitrogen ion beams with submillisecond duration and high-power density

Abstract

It has been shown, for the first time, that the impact of a repetitively pulsed nitrogen ion beam with a high-power density of 4–11.2 kW/cm2 on the surface of AISI 321 steel can significantly change the morphology, elemental and phase composition, microstructure, and operational properties of samples. Numerical modeling was used to demonstrate the dynamics of variations in the surface temperature of AISI 321 steel under the impact of a nitrogen ion beam with submillisecond duration. High-intensity implantation with nitrogen ion beams leads to the formation of ion-doped layers with a depth up to 25 μm in 60 min. The article provides the results of x-ray phase analysis of surface ion-doped layers of modified samples and transmission electron microscopy. Steel modification led to an increase in wear resistance up to 3585 times and an increase in hardness up to five times. Tribological studies showed a decrease in the friction coefficient by 30%.