1、Designation: A902 13aStandard TerminologyRelating to Metallic Coated Steel Products1This standard is issued under the fixed designation A902; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in pa
2、rentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This standard is a compilation of terminology related tometallic coatings used in the steel industry, and to the steel onwhich the coatings are ap
3、plied. Terms that are generallyunderstood or adequately defined in other readily availablesources are not included.1.2 When a term is used in an ASTM document for whichCommittee A05 is responsible it is included herein only whenjudged, after review by Subcommittee A05.18, to be a gener-ally usable t
4、erm.1.3 Definitions that are identical to those published by otherASTM committees or other standards organizations are iden-tified with the ASTM standard designation (for example,Terminology B374) or with the abbreviation of the name of theorganization.1.4 A definition is a single sentence with addi
5、tional infor-mation included in notes. The year the definition was adopted,or the year of latest revision, is appended. The responsiblesubcommittee reviews the definition for each term at five-yearintervals, and prepares revisions as needed.2. Referenced Documents2.1 ASTM Standards:2A641/A641M Speci
6、fication for ZincCoated (Galvanized)Carbon Steel WireA924/A924M Specification for General Requirements forSteel Sheet, Metallic-Coated by the Hot-Dip ProcessB374 Terminology Relating to ElectroplatingD6386 Practice for Preparation of Zinc (Hot-Dip Galva-nized) Coated Iron and Steel Product and Hardw
7、areSurfaces for PaintingD7396 Guide for Preparation of New, Continuous Zinc-Coated (Galvanized) Steel Surfaces for Painting3. Terminology3.1 Definitions:aluminized coating, na coating on steel consisting of eithercommercially-pure aluminum (Type 2) or aluminum-siliconalloy (Type 1), applied by the h
8、ot-dip process. (2005)barb, nas related to barbed wire, a short length of wire, withexposed ends cut on a bias to produce sharp points. (1995)barbed wire, na fabricated wire product consisting of twoline wires twisted to form a two-wire strand, into which2-point or 4-point barbs are tightly wrapped
9、and locked intoplace at specified intervals. (1995)base metal, nas related to metallic-coated steel, the steel towhich the coating is applied, as distinguished from thecoating metal. (1990)batch coating, nof metallic coated steel products, theprocess of discontinuous-sequential passage of steel arti
10、clesthrough the various steps of the coating process, such as,cleaning, pickling, fluxing, and coating. (1995)breaking strength, nas related to wire, the maximum forcedeveloped prior to fracture during tension testing of wire andwire products.DISCUSSIONIn testing of stranded wire products, the maxim
11、umforce may be developed after fracture of one or more individual wires.(1993)carbon steel, nsteel having a maximum carbon content of2.0 % and a composition conforming to the following: (1)nominimum content is specified for chromium, cobalt, colum-bium (niobium), molybdenum, nickel, titanium, tungst
12、en,vanadium, zirconium, or any other element added to obtaina desired alloying effect; (2) the specified minimum andmaximum values for copper do not exceed 0.35 % and0.60 %, respectively; (3) the specified maximum for any ofthe following elements does not exceed these percentages:manganese 1.65 %, s
13、ilicon 0.60 %, columbium (niobium)0.015 %, vanadium 0.008 %, boron 0.0008 %, or titanium0.025 %; and (4) the incidental content of the followingelements does not exceed these percentages: nickel, 0.20 %;chromium, 0.15 %; and molybdenum, 0.06 %.DISCUSSIONCarbon steels typically contain small quantiti
14、es ofcertain residual elements from the feed materials. When the quantity ofsuch retained elements exceeds the values listed in (4) above, the1This terminology is under the jurisdiction of ASTM Committee A05 onMetallic-Coated Iron and Steel Products and is the direct responsibility ofSubcommittee A0
15、5.18 on Editorial and Terminology.Current edition approved June 1, 2013. Published June 2013. Originallyapproved in 1990. Last previous edition approved in 2013 as A902 - 13. DOI:10.1520/A0902-13A.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service a
16、t serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959.
17、 United States1characteristics of the steel may differ from that of carbon steel withoutthose elements to a degree that the steel may be unsatisfactory for theintended use. The composition limits stated in this definition shall notapply to stabilized steel. (2005)chemical treatment, na passivating s
18、urface protectant nor-mally applied to metallic coatings to retard the formation ofcorrosion products during shipment and storage (storagestain).DISCUSSIONThe corrosion-inhibiting characteristics of chemicaltreatments are limited. If chemically-treated material becomes wet inshipment or storage, the
19、 product should be used or dried immediately.Some types of chemical treatments may be inappropriate in certainapplications because of possible undesirable effects on furtherprocessing, such as phosphatizing, spot welding, or painting. (2007)commercial steel, CS, na metallic-coated steel sheet desig-
20、nation which includes carbon steel products intended forgeneral fabrication applications involving little or no bend-ing or forming. (2013)DISCUSSIONThe chemical composition requirements for this desig-nation can be found in the appropriate sheet product specification.continuous coating, nof metalli
21、c coated steel products, theprocess of uninterrupted passage of long lengths of steelproducts, usually steel sheet, tube, pipe, or wire, through thevarious processing steps such as cleaning, annealing, andcoating.DISCUSSIONContinuous coating involves the use of equipment thatis capable of joining lo
22、ng lengths of product without stoppage of thecoating process. Continuous coating of preformed tube or pipe islimited to the outer surface, since the coating material cannot besupplied to the inner surface. (2006)delamination, nas related to metallic coated steel, theseparation of a coating (either f
23、ull or partial thickness) fromunderlying layers; the separation can occur in small localizedareas or large areas of surface.DISCUSSIONFlaking, peeling, and spalling are colloquial termssometimes used to describe the separation. (1997)differentially coated sheet, nmetallic coated sheet withunequal sp
24、ecifications for the weight (mass) of metalliccoating on each of the two surfaces. (2012)electrolytic process, nthe application of a metallic coatingon a steel product by passing an electric current through achemical solution in which the product is immersed; thecoating may be applied in a continuou
25、s process or a batchprocess. (1995)extra deep drawing steel, EDDS, na metallic-coated steelsheet designation, which requires the use of non-aging,chemically-stabilized carbon steel intended for applicationsrequiring maximum formability. (2013)DISCUSSIONThe chemical composition requirements for this
26、desig-nation can be found in the appropriate sheet product specification.extra smooth sheet, nproduct produced by cold rolling themetallic coated sheet with a small reduction in thickness toimpart both the desired surface texture and resistance tostretcher strains and fluting. (Syn. skin passed shee
27、t)DISCUSSIONExtra smooth is frequently specified when fluting orstretcher strains may be a hazard. Extra smooth may not be available inall coating types or weights (masses). (2012)fabricator, nas related to corrugated metal pipe,(1) theorganization that produces the finished pipe, or (2 ) forstructu
28、ral plate pipe, the organization that processes flatsheets and other items needed for the field assembly of thefinished products. (1990)flakingSee delamination. (1994)forming steel, FS, na metallic-coated steel sheet designationwhich includes carbon steel products intended for applica-tions involvin
29、g moderate forming or mild drawing whichmight not be achieved by commercial steel. (2013)DISCUSSIONThe chemical composition requirements for this desig-nation can be found in the appropriate sheet product specification.galvanized coating, na coating of virtually pure zinc onsteel, applied by various
30、 methods or processes includinghot-dip processes and electrodeposition (electrolytic pro-cesses).DISCUSSIONFor hot-dipped galvanized coatings, the molten bath istypically at least 99 % zinc; as applied to the steel, the coating typicallycontains intermetallic layers of zinc-iron alloys adjacent to t
31、he steelsurface. Other methods of applying the zinc coating include metalspraying (metallizing), sherardizing, vacuum deposition, and mechani-cal deposition, but there is not general agreement that all produce a“galvanized coating.” There is general agreement that the coatingproduced by application
32、of zinc-rich paint is not a “galvanizedcoating.” (1999)galvannealed coating, na coating on steel of zinc-basedalloy, containing about 6 to 15 % iron, produced by hot-dipimmersion in a high-zinc content coating bath, followed byheating the steel to induce diffusion alloying between themolten zinc coa
33、ting and the steel. (1994)heat, na specific lot of material representing a single melt ofsteel produced to a specified chemical analysis. (1991)heat analysis, nthe chemical composition of a specificproduction lot of liquid steel. (2003)DISCUSSIONThe sample on which the analysis is performed isusuall
34、y taken from the molten steel.hot-dip process, nthe application of a metallic coating on asteel product by immersion of the product in the moltenmetal which forms the coating; the coating is applied ineither a continuous process or a batch process. (2006)DISCUSSIONMetallic coatings applied by the ho
35、t-dip process arecharacterized by the presence of an intermediate alloy layer whichforms as a result of a metallurgical reaction between the steel surfaceand the molten metal.inclusion control, nthe process of reducing the volumefraction of inclusions or modifying the shape of inclusions toimprove f
36、ormability, weldability, and machinability.DISCUSSIONInclusions, especially those elongated during the rollingprocess, create the conditions for initiating, and/or propagating crackswhen the material is stretched or bent during the manufacture of a part.The adverse effects of inclusions are minimize
37、d by reducing the contentof inclusions in the steel and/or by altering the shape of inclusionsthrough the use of additions during the steelmaking process that changethe elongated shape of the inclusions to less harmful, small, well-dispersed globular inclusions. (2008)lot, na finite quantity of a gi
38、ven product, produced underconditions that are considered uniform for sampling pur-poses.A902 13a2DISCUSSIONIn the case of metallic-coated iron or steel products, theconditions which may be considered necessary for a single lot aresimilar units, coating at approximately the same time, in the sameman
39、ner, in a single coating bath. Consideration must also be given tothe uniformity of the iron or steel product to which the coating isapplied, such as being from a single heat. For material sampled aftershipment from the manufacturers or coaters facility (where the heat orprocessing identification ma
40、y have been lost), a lot would consist of allsimilar material in a given shipment. (2006)manufacturer, nas related to corrugated metal pipe, theorganization that produces the metal sheet from which pipeis made. (1990)mechanical polishing, nof metallic coatings, the looseningand detachment of superfi
41、cial, small particles of coatingmetal during processing or testing, due to mechanicalabrasion. (1994)minimum thickness, nof metallic-coated steel sheet,anordering designation which indicates that the applicabletolerance for thickness is all plus from the ordered thickness.(2013)nominal thickness, no
42、f metallic coated steel sheet,anordering designation which indicates that the applicabletolerance for thickness is divided equally, plus and minusfrom the ordered thickness. (2012)oiled, adjdescribing a coating applied to metallic coated steelsheet alone or in addition to chemical treatment for furt
43、herprotection against the onset of storage corrosion; the oilcoating is intended as a corrosion inhibitor only and not as arolling or drawing lubricant. (2001)peelingSee delamination. (1994)phosphatized, adjpertains to the treatment, in a phosphatesolution, of uncoated and metallic coated sheet to p
44、repare thesurface for painting without further treatment except normalcleaning. (Syn. phosphated, phosphate coated)DISCUSSIONThis is a surface treatment only and other characteris-tics of the metallic coating remain unchanged on phosphatized sheet.Additional information about this and other types of
45、 available surfacetreatments is presented in Appendix X2 of Specification A924/A924M.Cleaning procedures are described in Guides D6386 and D7396. (2009)powdering, nas related to metallic coatings, microcrackingand fine particle separation of generally brittle coatings whenthe coating is severely str
46、essed. (2005)product analysis, na chemical analysis of the semifinishedor finished steel. (1993)purchaser, nas related to corrugated metal pipe, the entitythat contracts to buy the finished pipe. (2009)sample, na portion of the material in a lot, selected accordingto a specific sampling plan, intend
47、ed to represent the lot.DISCUSSIONThe sample may consist of one or more discrete units,or may be one or more portions selected from one or more large units(such as from a coil of wire or steel sheet). (1994)seam, nin wire, a longitudinal discontinuity that extendsradially into the wire from its surf
48、ace.DISCUSSIONThe discontinuity may appear as a crack. The discon-tinuity can develop during solidification, rolling, or the wire drawingoperation as a result of dynamic strain aging.Aseam originating in wiredrawing is also known as a split. (1992)skin passed sheet, nSynonym for extra smooth sheet.(
49、1991)spallingSee delamination. (1997)spangle, nin hot-dip coatings, the crystalline structure thatdevelops on a metallic-coated surface when the moltencoating metal solidifies, especially on steel sheet and articlescoated after fabrication.DISCUSSIONThe crystalline structure can range from large, veryvisible dendritic grains to small, equiaxed grains that are difficult todiscern with the unaided eye. Variables that affect the crystal size andvisibility include: steel substrate composition and prior treatment,coating bath com
