310 S Stainless Steel In High Temperature Slag Corrosion Mechanism Research

Study on the corrosion of constructional engineering material in molten slag at high-temperature is of considerable industrial importance.310S stainless steel (310SSS) is one of the most utilized heat-resistant configuration steel used in high-temperature oxidizing environments. In this dissertation, corrosion mechanism of310SSS in melted slag at1150℃and1400℃by X-ray diffraction analysis, megalographic analysis, scanning electron microscope observation and energy spectrum analysis in order to improve the working life of310SSS in molten slag.Corrosion mechanism of310SSS in molten slag was expounded through discussing corrosion form, corrosion type, corrosion process, and the corrosion result.Corrosion form, of310SSS in molten lead-rich slag, was the high-temperature oxidation (HTO), corrosion type were intergranular corrosion (IGC) and pitting, the results revealed that the corrosion process was controlled by the redox reactions of PbO in the lead-rich slag with composition of310SSS.Corrosion form, of310SSS in molten copper slag, was the high-temperature vulcanization-oxidation (HTVO), corrosion type were IGC and pitting, the results revealed that the corrosion process was the reactions of S in the copper slag with composition of310SSS. Sulfides were deposited along the grain boundary.Corrosion form, of310SSS in molten nickel slag, was HTVO, corrosion types were IGC, the results revealed that the corrosion process was the reactions of S in the copper slag with composition of310SSS or impurity elements of310SSS were deposited on the grain boundary lead to brittle intercristal fracture.Corrosion form, of310SSS in molten tin slag, was HTO, corrosion type was IGC; the results showed that long strip structure was a separated chromium carbon, which accelerated corrosion at poor chromic area around chromium carbon. Chromium depletion of310SSS was attributed to the precipitation of (Fe, Cr)23C6along the grain boundary which results in the susceptibility to IGC.At the same temperatures, compared with copper slag, the lead-rich had stronger corrosion was attributed to it contained high content and strong oxidation PbO. Compared with tin slag, the nickel slag had stronger corrosion was attributed to it contained high content S. There were HTO and IGC the corrosion process of310SSS in molten slag.