TheeffectoftemperatureandoxygencontentontheflowingliquidmetalcorrosionofstructuralsteelsinthePb–BieutecticOriginalResearchArticle

Weperformedcorrosiontestsof1000heachonapproximately20typesofstructuralsteels(austenitic,ferriticandmartensitic)inconvectionloopswithflowingPb–Biat500,450and400°Candatemperaturegradientof100°C.TheseexperimentswereperformedinliquidPb–Biwithdifferentoxygenconcentrations(fromapproximately1×10−6to2×10−5wt.%)toascertainatwhatoxygenconcentrationanduptowhattemperaturetheoxygentechnologycancreateprotectiveoxideorspinellayerstoreduceorpreventcorrosion.TheresultsshowedthatthestructuralmaterialscontemplatedforbuildinganADSsystem,including9%Cr–1%Mo(W)martensiticsteelsandsimilarsteelswithahigherSicontent(2–3%),canbeusedwiththeirsurfaceunpassivatedatupto450°Candsufferonlyminimalcorrosion(upto5μm/year).Athighertemperatures,theirsurfacemustbepassivatedpriortoandregularlyduringtheoperation;however,notechnologytoperformsuchpassivationinthepresenceofPb–Biisknownthatthistime.Inaddition,wemeasuredtheimpactofvariousalloyingelements,suchasFe,Cr,Ni,Mn,Si,AlandMo,onthecorrosionofsuchsteelsandsearchedforpotentialwaystopassivatetheirsurfaceorcreateprotectiveoxideorspinellayersduringoperationbyvaryingtheamountofoxygeninliquidPb–Bi.