INTERPRETATION OF WASTAGE MECHANISMS OF MATERIALS EXPOSED TO ELEVATED-TEMPERATURE EROSION-CORROSION USING EROSION-CORROSION MAPS AND COMPUTER-GRAPHICS

One of the most significant advances in the study of erosion-oxidation and wear in recent years has been the development of theoretical meth ods to construct maps where the change in erosion or wear mechanism is given as a function of typically two parameters. This approach has im portant implications for optimization of process parameters in wear an d in erosion-corrosion. The direct application of such work is in proc ess engineering where guidelines on the control of parameters to minim ize erosion-corrosion are practically non-existent. Although there hav e been a range of excellent approaches towards the development of eros ion-oxidation maps there have been some areas which have not been addr essed. Firstly, because erosion-corrosion involves a wide range of par ameters, the maps which have been developed to date have only consider ed the effects of temperature and velocity. In addition, there has bee n no significant attempt to combine variables on the maps, or incorpor ate a materials selection parameter on the maps. Finally, there have b een few attempts to demonstrate the physical significance of the regim es on the maps, in order to clarify the mechanism of damage on the sur face. The object of this research is to address the above areas in the development work on the maps to date. It is shown how the maps can be used to show metal recession as opposed to erosion rates by modifying the regime definitions proposed to date. The relative advantages and limitations of the models developed to date will be discussed.