Withpricesformetalresourcessuchasnickelandmolybdenumsoaring,thereisaheightenedsenseofcrisisconcerningresourcescarcity.WhileType304,themostcommonstainlesssteel,offersexcellentcorrosionresistance,itspriceisaffectedsignificantlybythecostofnickelbecauseofits8%nickelcontent.ThestainlesssteelthathasthesamecorrosionresistanceasthatofType304anddoesnotcontainnickelandmolybdenumhasbeenrequired.JFESteelCorporationhasdevelopedanew21%Cr-0.4%Custainlesssteel,theworld’sfirstferriticstainlesssteel,whichoffersequivalentcorrosionresistancetoType304whilecontainingabsolutelynonickelormolybdenum,tworaremetals.Thenewlydevelopedsteelcontains21%chromiumwiththeadditionof0.4%copper.Thedevelopmentofthesteelisbasedonanewdiscoverythatthepassivefilmsofstainlesssteelscouldbestrengthenedbythesynergyeffectofhighchromiumcontentandcopperaddition.Copperadditionenrichesthechromiumcontentinpassivefilmsafterfieldexposure.Newlydeveloped21%Cr-0.4%CustainlesssteelisadoptedformanyapplicationsasasubstitutionforType304,includingcommercialkitchenware,buildingmaterialsandindustrialmachinery.ThesteelisexpectedtobeanewstandardofaferriticstainlesssteelasasubstitutionforType304.
