Designation:G15–07StandardTerminologyRelatingtoCorrosionandCorrosionTesting1ThisstandardisissuedunderthefixeddesignationG15;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(e)indicatesaneditorialchangesincethelastrevisionorreapproval.ThisstandardhasbeenapprovedforusebyagenciesoftheDepartmentofDefense.1.Scope1.1Thisterminologycoverscommonlyusedtermsinthefieldofcorrosion.RelatedtermsmaybefoundinTerminolo-giesD16,D4538,G40,orotherASTMterminologystan-dards.AlltermsdefinedbyASTMcommitteesmaybefoundintheASTMDictionaryofEngineering&Technology.2.ReferencedDocuments2.1ASTMStandards:D16TerminologyforPaint,RelatedCoatings,Materials,andApplicationsD4538TerminologyRelatingtoProtectiveCoatingandLiningWorkforPowerGenerationFacilitiesG40TerminologyRelatingtoWearandErosion3.TerminologyACimpedance—Seeelectrochemicalimpedance.active—negativedirectionofelectrodepotential.(Alsousedtodescribecorrosionanditsassociatedpotentialrangewhenanelectrodepotentialismorenegativethananadjacentde-pressedcorrosionrate[passive]range.)anion—negativelychargedion.anode—electrodeofanelectrolyticcellatwhichoxidationistheprincipalreaction.(Electronsflowawayfromtheanodeintheexternalcircuit.Itisusuallytheelectrodewherecorrosionoccursandmetalionsentersolution.)anodecorrosionefficiency—ratiooftheactualcorrosion(weightloss)ofananodetothetheoreticalcorrosion(weightloss)calculatedbyFaraday’slawfromthequantityofelectricitythathaspassed.anodicinhibitor—corrosioninhibitorwhoseprimaryactionistoslowthekineticsoftheanodicreaction,producingapositiveshiftincorrosionpotential.anodicpolarization—changeoftheelectrodepotentialinthenoble(positive)directionduetocurrentflow.(Seepolar-ization.)anodicprotection—techniquetoreducethecorrosionrateofametalbypolarizingitintoitspassiveregionwheredissolu-tionratesarelow.anolyte—electrolyteadjacenttotheanodeofanelectrolyticcell.auxi...
