Grazing incidence X-ray diffraction spectra analysis of expanded austenite for implanted stainless steel

This work proposed to investigate the structure of the modified austenite fcc phase due to ion implantation and called “expanded austenite” using grazing incidence angle X-ray diffraction (GIXRD) measurements combined with the application of a model for simulating X-ray diffraction peaks. Ion implantation of different atomic elements (N, Cr, Mo, Ag, Xe and Ar) have been carried in the near surface region of an austenitic 316LVM stainless steel (the implanted layer thickness did not exceed 60 nm). Mild ion implantation conditions were chosen to avoid the structural transformation of the steel: no ferrite and no amorphous phase were formed. The structure of the implanted layers was investigated by GIXRD at different incidence angles. A original model was proposed to simulate the X-Ray diffraction peaks. This model took into account the incidence angle, the ion implantation conditions (fluence and energy) through the concentration depth profile and finally the nature of the implanted ion through a k coefficient. All the recorded X-ray diffraction peaks were simulated with this model.