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The polarisation characteristics of the electropolishing process in a magnetic field (MEP – magnetoelectropolishing), in comparison with those obtained under standard/conventional process (EP) conditions, have been obtained. The occurrence of an EP plateau has been observed in view of the optimization of MEP process. Up-to-date stainless steel surface studies always indicated some amount of free-metal atoms apart from the detected oxides and hydroxides. Such a morphology of the surface film usually affects the thermodynamic stability and corrosion resistance of surface oxide layer and is one of the most important features of stainless steels. With this new MEP process we can improve metal surface properties by making the stainless steel more resistant to halides encountered in a variety of environments. Furthermore, in this paper the stainless steel surface film study results have been presented. The results of the corrosion research carried out by the authors on the behaviour of the most commonly used material − medical grade AISI 316L stainless steel both in Ringer’s body fluid and in aqueous 3% NaCl solution have been investigated and presented earlier elsewhere, though some of these results, concerning the EIS Nyquist plots and polarization curves are also revealed herein. In this paper an attempt to explain this peculiar performance of 316L stainless steel has been undertaken. The SEM studies, Auger electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS) were performed on 316L samples after three treatments: MP – abrasive polishing (800 grit size), EP – conventional electrolytic polishing, and MEP – magnetoelectropolishing. It has been found that the proposed magnetoelectropolishing (MEP) process considerably modifies the morphology and the composition of the surface film, thus leading to improved corrosion resistance of the studied 316L SS.

A mixed quantum mechanical and Monte Carlo method for calculating Auger spectra from nanoclusters is presented. The approach, based on a cluster method, consists of two steps. Ab initio quantum mechanical calculations are first performed to obtain accurate energy and probability distributions of the generated Auger electrons. In a second step, using the calculated line shape as electron source, the Monte Carlo method is used to simulate the effect of inelastic losses on the original Auger line shape. The resulting spectrum can be directly compared to "as-acquired" experimental spectra, thus avoiding background subtraction or deconvolution procedures. As a case study, the O K-LL spectrum from solid SiO 2 is considered. Spectra computed before or after the electron has traveled through the solid, i.e., unaffected or affected by extrinsic energy losses, are compared to the pertinent experimental spectra measured within our group. Both transition energies and relative intensities are well reproduced.

Quasi-elastic scattering of 1-2 keV electrons is considered with respect to measuring the H content in hydrogenated amorphous carbon (a-C : H) materials. Interest in the technique lies in the fact that H cannot be typically detected by electron spectroscopic means (AES or XPS for instance). The feasibility of the approach is demonstrated and a quantification procedure is proposed. At the same time however, limitations of the technique (electron stimulated H desorption, low intensity of the H related signal and its spectral interference with the π -plasmon peak) are discussed.

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