The interfacial phenomena between carbonaceousmaterials such as graphite, coke ,and char and Fe一C一S meltsare important due to the extensive use of these materials in ironprocessing furnaces. However, the understanding of theinterfacial phenomena between these kinds of carbomaceorsmaterials and molten iron alloys is far from complete. In thisstudy ,graphite was selected as the solid carbonaceous materialbecause its atomic structure has been well established. Thesesslie drop method was adopted in this investigation to measurethe contact angle between solid graphite and molten iron and tostudy the interfacial phenomena. The influence of carbon andsulfur content in Fe一C一S melts on the wettability of solidgraphite has been investigated at 1600℃.The melt carboncontent was in the range of 0.13 to 2.24 wt pct, andthe melt sulfur content was in the range of 0.05 to 0.37wt pct .X-ray energy-dispersive spectrometer(EDS)analysis was conducted on an HITACHIS-4500scanning electron microscope to detect compositiondistribution at the interfacial region. It was foundthat contact of solid graphite with Fe一C一S melts willresult in a nonequilibrium reactive wetting. It involved xarbontransfer from the solid to the liquid and iron transfer from theliquid to the solid. The Fe一C一S melts exhibited relativelypoor wetting when the reactions were absent. The mass transferbetween solid graphite and Fe一C一S melts was observed tostrongly enhance the wetting phenomena. It is proposed that thedecrease of system free energy corresponding to the masstransfer reactions strongly influences the formation of theinterface region and results in the progressive spreading of thewetting line. The composition and thickness of the graphite/ironinterfacial layer was dependent on the intensity of mass transferacross the interface. The resulting change in the interfacialenergyγls is a strong function of mass transfer, and it varies inaccordance with time of contact. The influence of carboncontent on the wetting phenomena could only be seen at in theinitial stages, whereas the influence of sulfur on the wettabilitywas found when the system approached equilibrium.Therefore ,the interfacial tension in its equilibrium condition atthe graphite/ Fe一C一S melt interface was determined only bythe extent of sulfur adsorption at this interface.
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