Designation:C455−07(Reapproved2013)StandardClassificationofChrome,Chrome-Magnesia,Magnesia-Chrome,andMagnesiaBrick1ThisstandardisissuedunderthefixeddesignationC455;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thisclassificationcategorizesmachine-maderefractorybrickdefinedaschrome,chrome-magnesia,magnesia-chrome,andmagnesiabrick(see3.1).Itdoesnotcoverproductsmadefromelectricallyfusedmagnesiumoxideortoproductsmadebyfusioncasting.Itspurposeistodescribeclassesdistin-guishedbyobviousdifferencesinmagnesiumoxide(MgO)contentexceptforchromebrick.1.2Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:C71TerminologyRelatingtoRefractories2NOTE1—Chemicalanalysisofrefractoryproductisdeterminedbyacombinationofx-rayfluorscence(XRF)andinductivelycoupledplasma(ICP)usingstandardreferencematerials(SRM),includingvarioustypesofmineralsandrefractorymaterialswhichareavailablefromtheNationalInstituteofStandardsandTechnologyandotherappropriatesources.3.Terminology3.1Fordefinitionsoftermsusedinthisclassification,seeTerminologyC71.4.SignificanceandUse4.1Thisclassificationcategorizesthedefinedtypesofrefractorybrick,withtheexceptionofchromebrick,intodistinctclassesbasedonanominalandminimalvalueformagnesiumoxidecontent.Chromebrickaretreatedasaseparateclasswithoutreferencetomagnesiumoxidecontent.Suchclasseshavehistoricallybeengenerallyusefulinrelatingthedefinedtypestospecificindustrialapplicationsandindevelopingproductorpurchasingspecifications.5.BasisofClassification5.1Chrome-magnesia,magnesia-chrome,andmagnesiabrickareclassifiedbyMgOcontentasshowninTab...
