ABSTRACT
Abstract ................................................................................................. 170 14.1 Introduction ................................................................................ 170 14.2 Experimental Part ....................................................................... 171 14.3 Results and Discussion .............................................................. 174 14.4 Conclusions ................................................................................ 183 Keywords .............................................................................................. 184 References ............................................................................................. 184
ABSTRACT
The degree of modification of the surface layer of Armco iron by sulfur, produced by sliding friction of the metal sample against: ebonite, sulfur vulcanizate of styrene-butadiene rubber (SBR), polysulphone or polysulfide rubber, was studied. Time of Flight Secondary Ion Mass Spectroscopy (TOF-SIMS) and confocal Raman microscopy techniques, both confirmed on the presence of iron sulfide (FeS) in the surface layer of metal counterface after tribological contact with SBR or polysulfide rubber. For the friction couple iron-ebonite, the presence of FeS was confirmed only by TOF-SIMS spectra. FT-Raman analysis indicated only on some oxides and unidentified hydrocarbon fragments being present. Any sulfur containing species were not found in the surface layer of iron counterface due to friction of the metal against polysulphone. The degree of iron modification is determined by the loading of friction couple, but also depends on the way sulfur is bonded in polymer material. Possibility for modification is limited only to materials, which contain sulfur either in a form of ionic sulfide crosslinks (SBR and ebonite) or side chains (polysulfide rubber). Degradation of polymer macromolecules during friction (polysulphone and ebonite – in this case under high loading) does not lead to the formation of FeS. Chemical reaction between sulfur and iron takes place only in the case of ionic products of polymer destruction containing sulfur.
14.1 INTRODUCTION
