Mechanical and Tribological Properties of LDX2101 Duplex Stainless Steel Submitted to Glow Discharge Ion Nitriding

In this paper, the mechanical and tribological properties of LDX2101 duplex stainless steel submitted to glow discharge (GD) nitriding and conventional ion beam nitrogen implantation (II) are reported. Different combinations of rich and poor nitrogen/hydrogen atmospheres and working GD temperatures are employed. Nitrogen II at room temperature and 350°C was performed at different energies and fluences in order to obtain a plateau distribution around 27 at.% until a depth of 400 nm. X-ray diffraction investigation indicated that the poor nitrogen atmosphere in GD processes is more efficient to produce expanded austenite and nitride precipitates at all temperatures. Nitrogen II, even at high temperature, produced only expanded austenite. The hardness of the nitrided surface region is about 18 GPa compared to ~ 3.3 GPa of the pristine condition. Wear resistance can be improved by one order of magnitude, independent of the GD nitrogen/hydrogen atmosphere, even at 300°C, where only expanded austenite is present.