Features of Surface Nitriding Revealed by Mössbauer Spectroscopy

抄録

Two different nitriding surface treatments of austenitic stainless steel have been studied: gaseous nitriding in a NH₃-H₂ mixture performed at temperatures between 700 and 900°C and nitrogen ion implantation with different dose rates between 5×10¹⁶ to 1.5×10¹⁷ N₂⁺ ions cm^–2 and different current densities between 1 to 5 μA cm^–2. The microstructure of the coating was studied by X-ray diffraction and Mössbauer spectroscopy. The discussion emphasizes the role of thermodynamical equilibrium conditions at high temperatures and of the process parameters at low temperatures on the phases which constitute the layer.