Synergism between abrasion and corrosion

The first objective of this research was to develop methodology for investigating and monitoring the three-body tribocorrosion of engineering alloys. A novel tribometer was designed that allowed for testing a concurrent action of three-body abrasion and corrosion using electrochemical techniques. The capabilities of the tribometer were examined by investigating 316L stainless steel tribocorrosion in a neutral environment. The influence of parameters such as load, sliding distance and rotation effect on threebody abrasion-corrosion was analysed and the rig performance was compared against other tribometers described in the literature (Chapter 2). The application of conventional and in-situ electrochemical methods for testing materials having different passivating ability and pitting tendency was studied (Chapter 3). The second objective of the research was to focus on applying the new methodology in the study of three-body tribocorrosion of wear resistant alloys, such as high-chromium cast irons (HCCI) and tungsten carbide claddings. Corrosion-only and corrosive wear behaviour of HCCIs in different pH conditions and in the presence of aggressive ions was thoroughly researched (Chapter 4 and 5). The structure of the HCCIs passive layer was investigated using NanoSIMS and Electron Microprobe and a corrosion mechanism of these alloys was proposed (Chapter 6). Then, round and angular tungsten carbide composites were studied in a neutral environment and their corrosion-only and tribocorrosion mechanisms were addressed (Chapter 7).