NACE G193 REV D-2012 Standard Terminology and Acronyms Relating to Corrosion (Item No 21137).pdf

1、Designation: NACE/ASTM G193 12dStandard Terminology and Acronyms Relating toCorrosion1This standard is issued under the fixed designation; the number immediately following the designation indicates the year of originaladoption or, in the case of revision, the year of last revision. A number in paren

2、theses indicates the year of last reapproval.1. Scope1.1 This terminology and acronyms standard covers anddefines commonly used terms and acronyms in the field ofcorrosion. Related terms may be found in Terminologies D16,D4538, G40, or other ASTM terminology standards.1.2 This terminology and acrony

3、ms standard is a result of anagreement between NACE International and ASTM Interna-tional Committee G01 on Corrosion of Metals and may notreflect the opinions of other ASTM committees.1.3 In this terminology and acronyms standard, brackets areused for directives that follow a definition and are obvi

4、ouslynot part of it, such as, “see XXX” and “also known asXXX.” Brackets can also indicate the field of application orcontext of the definition or acronym.2. Referenced Documents2.1 ASTM Standards:2D16 Terminology for Paint, Related Coatings, Materials,and ApplicationsD2583 Test Method for Indentati

5、on Hardness of RigidPlastics by Means of a Barcol ImpressorD4538 Terminology Relating to Protective Coating andLining Work for Power Generation FacilitiesE10 Test Method for Brinell Hardness of Metallic MaterialsE18 Test Methods for Rockwell Hardness of Metallic Ma-terialsE92 Test Method for Vickers

6、 Hardness of Metallic Materi-als3G40 Terminology Relating to Wear and Erosion2.2 NACE Standards:2NACE No. 1/SSPC-SP 5 White Metal Blast CleaningNACE No. 2/SSPC-SP10 Near-White Metal Blast CleaningNACE No. 3/SSPC-SP 6 Commercial Blast CleaningNACE No. 4/SSPC-SP 7 Brush-Off Blast Cleaning2.3 SSPC Surf

7、ace Preparation Standards:4SSPC-SP 1 Solvent CleaningSSPC-SP 2 Hand Tool CleaningSSPC-SP 3 Power Tool CleaningSSPC-SP 8 Pickling2.4 ISO Standards:5ISO 6506-1 Metallic materials - Brinell hardness test -Part 1: Test methodISO 6507-1 Metallic materials - Vickers hardness test -Part 1: Test methodISO 6

8、508-1 Metallic materials - Rockwell hardness test -Part 1: Test method (scales A, B, C, D, E, F, G, H, K, N,T)3. Terminology3.1 Definitions:abrasion resistancethe ability of a material to resist beingworn away and to maintain its original appearance andstructure when subjected to rubbing, scraping,

9、or wear.abrasivea solid substance that, owing to its hardness,toughness, size, shape, consistency, or other properties, issuitable for grinding, cutting, roughening, polishing, orcleaning a surface by friction or high-velocity impact.abrasive blast cleaningcleaning and roughening of a sur-face produ

10、ced by the high-velocity impact of an abrasive thatis propelled by the discharge of pressurized fluid from a blastnozzle or by a mechanical device such as a centrifugalblasting wheel. also referred to as abrasive blastingabrasive blastingsee abrasive blast cleaning.acceleratora chemical substance th

11、at increases the rate atwhich a chemical reaction (e.g., curing) would otherwiseoccur.AC impedancesee electrochemical impedance.acrylictype of resin polymerized from acrylic acid, meth-acrylic acid, esters of these acids, or acrylonitrile.activatora chemical substance that initiates a chemicalreacti

12、on (e.g., curing). Heat and radiation may also serve asactivators for some chemical reactions.active(1) a state of a metal surface that is corroding withoutsignificant influence of reaction product. (2) the negativedirection of electrode potential.active-passive cellan electrochemical cell in which

13、the1This terminology and acronyms standard is under the jurisdiction of NACE/ASTM Committee J01, Joint Committee on Corrosion, and is the direct responsi-bility of Subcommittee J01.02, Working Group on Terminology.Current edition approved Dec. 1, 2012. Published February 2013. Originallyapproved in

14、2009. Last previous edition approved in 2012 as G19312c. DOI:10.1520/G0193-12D.2For referenced ASTM standards, visit the ASTM Web site, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page

15、onthe ASTM Web site. For NACE standards, visit the NACE Web site, www.nace.org,or contact NACE FirstService at firstservicenace.org.3Withdrawn. The last approved version of this historical standard is referencedon www.astm.org.4Available from The Society for Protective Coatings (SSPC), 40 24th St.,

16、6thFloor, Pittsburgh, PA 15222-4656, http:/www.sspc.org.5Available from International Organization for Standardization (ISO), 1, ch. dela Voie-Creuse, Case postale 56, CH-1211, Geneva 20, Switzerland, http:/www.iso.org.1 NACE International/ASTM International 2012 All rights reserved anode is a metal

17、 in the active state and the cathode is thesame metal in the passive state.adduct curing agenta material that is formed by prereactingthe curing agent with a portion of the resin component of thecoating.adhesionthe state in which two surfaces are held together bychemical interfacial forces, mechanic

18、al interlocking forces,or both.aeration cellsee differential aeration cell.aging(1) the process of exposing materials to an environ-ment for an interval of time. (2) change in metallurgicalproperties that generally occurs slowly at room temperature(natural aging) and more rapidly at higher temperatu

19、re(artificial aging).air dryingprocess by which an applied wet coat converts toa dry coating film by evaporation of solvent or reaction withoxygen as a result of simple exposure to air withoutintentional addition of heat or a curing agent.airless sprayingprocess of spraying coating liquids usinghydr

20、aulic pressure, not air pressure, to atomize.alkydtype of resin formed by the reaction of polyhydricalcohols and polybasic acids, part of which is derived fromsaturated or unsaturated oils or fats.alligatoringpronounced wide cracking over the surface of acoating, which has the appearance of alligato

21、r hide.alloy steelan iron-based alloy containing carbon (usuallyless than 2.5 mass percent), manganese (usually greater than0.25 mass percent), and specified minimum quantities of oneor more alloying elements other than manganese, silicon,and copper, but does not contain 10.5 mass percent or greater

22、chromium.alternate immersionexposure to environmental cycles,each involving immersion in a fluid for a period of timefollowed by removal from that fluid for another period oftime.amphoteric metala metal that is susceptible to corrosion inboth acidic and alkaline environments.anaerobicabsence of air

23、or free (molecular) oxygen.anchor patternsee surface profile.aniona negatively charged ion.annealheat to and hold at a temperature appropriate for thespecific material and then cool at a suitable rate, for suchpurposes as reducing hardness, improving machinability, orobtaining desired properties.ano

24、dethe electrode of an electrochemical cell at whichoxidation occurs. (Electrons flow away from the anode in theexternal circuit. It is usually the electrode where corrosionoccurs and metal ions enter solution.)anode capan electrical insulating material placed over theend of the anode at the lead wir

25、e connection.anode corrosion efficiencythe ratio of the actual corrosion(mass loss) of an anode to the theoretical corrosion (massloss) calculated from the quantity of electricity that haspassed between the anode and cathode using Faradays law.anodic inhibitora corrosion inhibitor whose primary acti

26、onis to reduce the rate of the anodic reaction, producing apositive shift in corrosion potential.anodic polarization(1) the change of electrode potentialcaused by an anodic current flowing across the electrode/electrolyte interface. (2) a forced noble (positive) shift inelectrode potential. See pola

27、rization.anodic protectiona technique to reduce the corrosion rate ofa metal surface by polarizing that surface to a more oxidizingpotential.anodizingan electrochemical oxidation process that con-verts the surface of a metal (such as aluminum or titanium)to an oxide coating.anolytethe electrolyte ad

28、jacent to the anode of an electro-chemical cell.antifoulingpreventing fouling. See fouling.atmospheric zonethe portion of a marine structure thatextends upward from the splash zone and is exposed to sun,wind, water spray, and rain.attenuationelectrical losses in a conductor caused by cur-rent flow i

29、n the conductor.Auger electron spectroscopyanalytical technique in whichthe sample surface is irradiated with low-energy electronsand the energy spectrum of electrons emitted from thesurface is measured.austenitethe face-centered cubic crystalline phase of iron oriron-based alloys.austenitic/ferriti

30、c stainless steelsee duplex stainless steel.austenitizingforming austenite by heating iron or iron-basedalloys to a temperature in the transformation range (partialaustenitizing) or above the transformation range (completeaustenitizing).auxiliary electrodesee counter electrode.backfillmaterial place

31、d in a hole to fill the space around theanodes, vent pipe, and buried components of a cathodicprotection system.Barcol hardnessa hardness value obtained by measuring theresistance of rubbers, plastics, or coatings to indentation bya steel impressor under spring load in accordance with TestMethod D25

32、83.barrier coating(1) a coating that has a high resistance topermeation of liquids and/or gases. (2) a coating that isapplied over a previously coated surface to prevent damageto the underlying coating during subsequent handling.barrier pigmenta pigment that impedes permeation throughan organic coat

33、ing solely by its physical presence contrastwith corrosion-inhibitive pigment and sacrificial pig-ment.beach marksthe characteristic markings on the fracturesurfaces produced by fatigue crack propagation. also knownas arrest marks, clamshell marks, and conchoidal marksbeta curvea plot of dynamic (fl

34、uctuating) interferencecurrent or related proportional voltage (ordinate) versus thecorresponding structure-to-electrolyte potentials at a se-lected location on the affected structure (abscissa).binderthe nonvolatile portion of the vehicle of a formulatedcoating material.bituminous coatingan asphalt

35、 or coal-tar compound used toprovide a protective coating for a surface.blast angle(1) the angle of the blast nozzle with reference toNACE/ASTM G193 12d2 NACE International/ASTM International 2012 All rights reserved the surface during abrasive blast cleaning. (2) the angle ofthe abrasive particles

36、propelled from a centrifugal blastingwheel with reference to the surface being abrasive blastcleaned.blistera dome-shaped projection on the surface of a coatingresulting from the local loss of adhesion and lifting of thefilm from an underlying coat or from the base substrate.bloomingsee blushing.blo

37、wdown(1) the injection of air or water under highpressure through a tube to the anode area for the purpose ofpurging the annular space and possibly correcting highresistance caused by gas blockage. cathodic protection use(2) the process of discharging a significant portion of theaqueous solution in

38、order to remove accumulated salts,deposits, and other impurities. boiler or cooling water toweruseblushingwhitening and loss of gloss of a coating, usuallyorganic, caused by moisture. also known as bloomingbracelet anodea galvanic anode with geometry suitable fordirect attachment around the circumfe

39、rence of a pipeline.This may be a half-shell bracelet consisting of two semicir-cular sections or a segmented bracelet consisting of a largenumber of individual sections.braze(1) a bond produced as the result of heating anassembly to the brazing temperature greater than 450 C840 F and less than the

40、solidus temperature of the basemetal using a brazing filler metal distributed and retainedbetween the closely fitted faying surfaces of the joint bycapillary action. (2) the act of creating a braze.breakdown potentialthe least noble potential at whichpitting or crevice corrosion, or both, will initi

41、ate andpropagate in a specific environment.Brinell hardnesshardness value, measured in accordancewith ISO 6506-1 or Test Method E10, usinga1to10mmdiameter tungsten carbide ball and a force of approximately9.807 to 29.420 N (1 to 3000 kgf).brittle fracturefracture that occurs with little or no plasti

42、cdeformation of the material. contrast with ductile fracturebrush-off blast cleaned surfacean abrasive blast cleanedsteel surface that is free of all visible contaminants andforeign matter but may have some tightly adherent millscale, rust, or coating. See NACE No. 4/SSPC-SP 7 fordetailed specificat

43、ion.burnishprocess of smoothing surfaces using frictional con-tact between the material and some other hard pieces of hardmaterial (e.g., hardened steel balls).calcareous coatinga layer consisting of calcium carbonateand other salts deposited on the surface. When the surface iscathodically polarized

44、 as in cathodic protection, this layer isthe result of the increased pH adjacent to the protectedsurface.calcareous depositsee calcareous coating.carbon steelalloy of carbon and iron containing up to 2 masspercent carbon and up to 1.65 mass percent manganese andresidual quantities of other elements,

45、 except those intention-ally added in specific quantities for deoxidation (usuallysilicon and/or aluminum).carburizingthe absorption and diffusion of carbon in iron oran iron-based alloy in contact with a suitable carbonaceousenvironment at elevated temperature.case hardeninghardening a ferrous allo

46、y so that the outerportion, or case, is made substantially harder than the innerportion, or core. Typical processes are carburizing, cyanid-ing, carbonitriding, nitriding, induction hardening, and flamehardening.casein paintwater-thinned paint with vehicle derived frommilk.cast irona generic term fo

47、r a large family of cast ferrousalloys in which the carbon content exceeds the solubility ofcarbon in austenite at the eutectic temperature, or about 2mass percent. Most cast irons also contain silicon, and maycontain other alloying elements and impurities.casting(1) a component formed at or near it

48、s finished shapeby the solidification of liquid material in a mold; (2) thecreation of such a component.catalysta chemical substance, usually present in smallamounts relative to the reactants, that increases the rate atwhich a chemical reaction (e.g., curing) would otherwiseoccur, but is not consume

49、d in the reaction.cathodethe electrode of an electrochemical cell at whichreduction is the principal reaction. (Electrons flow towardthe cathode in the external circuit.)cathodic corrosioncorrosion of a metal when it is a cathode,usually caused by the reaction of an amphoteric metal withthe alkaline products of electr