Wear Behavior of Hardfacing Coatings Applied on Glass Processing Tools



Wear is major life limiting factor of the glass processing tools. A complex interaction of hot viscous glass and oxide layers at tool surface, damages tool by cyclic contact. Hardfacing is one of the most useful and economical ways to improve the performance of components submitted to severe wear conditions. The specific wear behavior of a hardfacing coating depends on its chemical composition, the microstructure obtained after hardfacing process, and finally the harfacing technology used to apply them. The main objective of this study was to evaluate wear behavior for coatings applied by various hardfacing techniques consist of gas tungsten arc (TIG) welding, plasma transferred arc (PTA) welding, and chromizing. Two different commercial cobalt based hardfacing electrodes (Stellite 12 and Tribaloy T-401) were employed to investigate the effect of the hardfacing alloys. In order to simulate real field conditions on a lab scale, tests were performed with a specially designed system and actual process parameters. The qualitative evaluation of wear behavior was supported by microstructural investigations using optical microscopy and scanning electron microscopy (SEM + EDS). The quantitative investigations were performed using profilometry and hardness tests. The results showed the superiority of PTA welding in comparison with other hardfacing techniques. The best wear resistance was obtained in PTA welding hardfacing with Stellite 12 alloy.