AES-XPS study of chromium carbides and chromium iron carbides

The nature of chromium rich carbides which precipitate at grain boundaries in steels is still not perfectly understood. We performed a multitechnique approach on model chromium carbide and chromium-iron carbide samples: Auger Electron Spectroscopy (AES), X-ray Photoelectron Spectroscopy (XPS), X-ray Diffraction (XRD), and High Energy Electron Diffraction (HEED) were used t o characterise the samples. Significant chemical shifts were observed for t he Cr, Fe and C XPS peaks in the M7C3 compound (M stands for metal), indica ting unambiguously that the compound formed is a mixed iron-chromium carbid e. (C) 1999 Elsevier Science B.V. All rights reserved.