ASTM G33-1999(2015) Standard Practice for Recording Data from Atmospheric Corrosion Tests of Metallic-Coated Steel Specimens《金属涂覆钢试样的大气腐蚀试验数据记录的标准实施规程》.pdf

1、Designation: G33 99 (Reapproved 2015)Standard Practice forRecording Data from Atmospheric Corrosion Tests ofMetallic-Coated Steel Specimens1This standard is issued under the fixed designation G33; the number immediately following the designation indicates the year of originaladoption or, in the case

2、 of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscriptepsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice covers a procedure for recording data ofatmospheric corrosion tests of metalli

3、c-coated steel specimens.Its objective is the assurance of (1) complete identification ofmaterials before testing, (2) objective reporting of materialappearance during visual inspections, and (3) adequatephotographic, micrographic, and chemical laboratory examina-tions at specific stages of deterior

4、ation, and at the end of thetests.1.2 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limita

5、tions prior to use.2. Referenced Documents2.1 ASTM Standards:2A90/A90M Test Method for Weight Mass of Coating onIron and Steel Articles with Zinc or Zinc-Alloy CoatingsA428/A428M Test Method for Weight Mass of Coating onAluminum-Coated Iron or Steel ArticlesE376 Practice for Measuring Coating Thickn

6、ess byMagnetic-Field or Eddy-Current (Electromagnetic) Test-ing MethodsG46 Guide for Examination and Evaluation of Pitting Cor-rosion3. Significance and Use3.1 Use of this practice will maximize the benefits to begained from atmospheric testing of metallic-coated steel. It willalso aid in comparing

7、results from one location to anotherwhere similar tests have been conducted.4. Data to be Recorded Before Testing4.1 Material Characteristics:4.1.1 Coating and Basis Metal:4.1.1.1 Type of coating (zinc, aluminum, nickel-chromium,and so forth).4.1.1.2 Method of application (hot-dip, electroplated,ele

8、ctroless, mechanical plated, and so forth),(1) Area coated (if not 100 % of surface),(2) Pre-treatment (basis metal: flux, sand-blast, and soforth), and(3) Post-treatment (heating, sealing, and so forth),4.1.1.3 Coating composition,4.1.1.4 Basis metal product.(1) Basis metal composition, and(2) Meta

9、llurgical history prior to coating (if any).4.1.1.5 Chemical treatment of coating.4.1.1.6 Black and white photograph of typical surface areaillustrating texture (1:1 magnification ratio).4.1.1.7 Micrograph of typical coating cross section (magni-fication and etchant to be specified).4.1.2 Coating We

10、ight and Thickness:4.1.2.1 Weight by stripping. (See Test Method A90/A90Mor A428/A428M.)(1) Method.4.1.2.2 Measured Thickness.(1) Method (for example, eddy current, back scattering,magnetic),NOTE 1If a magnetic type instrument is used, refer to Practice E376.(2) Number of determinations,(3) Mean,(4)

11、 Standard deviation, and(5) Range (spread of determinations).4.2 Specimen Identification and Exposure Location:4.2.1 Marking (method to be specified).4.2.2 Specimen position in test area.4.2.3 Angle of exposure from horizontal.4.2.4 Direction of specimen faces.4.2.5 Location of test area.4.2.6 Descr

12、iption of test area (location of nearby industry,ocean, and so forth, and recorded data on specific contaminantswhere possible).1This practice is under the jurisdiction of ASTM Committee G01 on Corrosionof Metals and is the direct responsibility of Subcommittee G01.04 on AtmosphericCorrosion.Current

13、 edition approved Nov. 1, 2015. Published November 2015. Originallyapproved in 1972. Last previous edition approved in 2010 as G3399(2010). DOI:10.1520/G0033-99R15.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Boo

14、k of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14.2.7 Exposure starting date:4.2.7.1 Weather conditions (for example, bright, cloud

15、y,sunshine, rain, and so forth),4.3 Specimen Characteristics:4.3.1 Description (sheet, wire, hardware, and so forth).4.3.2 Specimen size:4.3.2.1 Specimen surface dimensions.4.3.2.2 Gage or thickness.4.3.3 Specimen weight (when applicable).4.3.4 Edge condition (to be specified).4.3.5 Specimen prepara

16、tion (method of cleaning).4.3.6 Surface appearance (verbal description, color, texture,and so forth) (see 5.3).5. Data to be Recorded During Field Inspections5.1 Specimen Identification:5.1.1 Marking.5.1.2 Position in test area.5.2 Exposure Period and Location:5.2.1 Location.5.2.2 Inspection date.5.

17、2.2.1 Weather conditions (for example, bright, cloudy,sunshine, rain, and so forth).5.3 Specimen Appearance (Top and Bottom Sides Should beRated Separately):5.3.1 Color:5.3.1.1 Hueshould be described by the following terms:red, orange, yellow, green, blue, violet, white, brown, gray, andblack. Combi

18、nation colors should be described by combiningterms, for example, yellow-brown.5.3.1.2 Brillianceshould be described by light or dark.5.3.1.3 Saturationshould be described by pale or vivid.5.3.1.4 Areaof the specimen affected should be expressedin percent.5.3.2 Surface Texture:5.3.2.1 The following

19、terms should be used to describe thesurface texture:(1) LustrousHaving a high degree of specularreflectivity,(2) Semi-lustrousHaving a slight degree of reflectivity,(3) MatteWithout gloss or luster but having a smoothsurface to touch,(4) ChalkyHaving a matte surface with a powderysurface layer that

20、can be wiped off with a finger touch,(5) GrainyHaving a uniformly roughened surface detect-able by touch, and(6) PebblyHaving a rough and irregularly indented sur-face.5.3.2.2 The area of the specimen affected should be ex-pressed in percent.5.3.3 Local Surface Irregularities:5.3.3.1 The following t

21、erms should be used to describesurface irregularities:(1) BlisteringAny separation of the coating from thesubstrate not accompanied by peeling,(2) PeelingSeparation of the coating from the substrateinitiating at an edge of or cut in the coating and causing anexposure of the substrate,(3) CrackingAny

22、 fissure in the coating other than amechanical cut,(4) CheckingCracking in a cross-hatch manner resem-bling mud cracking,(5) RustCorrosion products of iron characterized byrough, reddish brown particles. Rust is always rough to thetouch,(6) TuberclesKnob-like protrusions of corrosionproducts,(7) Nod

23、ulesLittle lumps, and(8) PitsCavities or holes in the metal surface.5.3.3.2 Blisters, cracks, nodules, tubercles, and pits shouldbe reported by number and size. Peeling, checking, and rustshould be reported by percent area affected.6. Data to Be Recorded When Samples Are Removed atthe Conclusion of

24、the Test6.1 Specimen Identification:6.1.1 Marking.6.1.2 Position in test area.6.2 Exposure Period and Location:6.2.1 Location.6.2.2 Weather conditions (for example, bright, cloudy,sunshine, rain, and so forth).6.2.3 Removal date.6.2.4 Exposure time in years (fractions as decimals tonearest tenth).6.

25、3 Specimen Appearance (Top and Bottom Sides Should beRated Separately) (See 5.3):6.3.1 Color.6.3.2 Surface texture.6.3.3 Local surface irregularities.6.4 Specimen Characteristics:6.4.1 Black and white photographs to illustrate typicalfeatures (magnification ratio 1:1).6.4.2 Microsections of coating

26、on panel to be specified atbeginning of tests to record any inter-granular corrosion,penetration to base metal, penetration along base metal-coatinginterface, nature of attack at the heaviest corrosion site on thespecimen, and other significant details (magnification andetchant to be specified).6.5

27、Coating Mass Loss and Thickness Determination:6.5.1 Coating mass determined by stripping (mass loss).6.5.1.1 Removal of corrosion product-method.6.5.1.2 Weight before stripping.6.5.1.3 Stripping of coating-method.6.5.1.4 Weight after stripping.6.5.1.5 Mass loss of control (unexposed panel(s) usingab

28、ove procedure (6.5.1).6.5.1.6 Net mass loss due to exposure after applying controlpanel correction (mass loss exposed panel(s) minus mass losscontrol panel(s).6.5.2 Measured coating thickness after cleaning.6.5.2.1 Method.G33 99 (2015)26.5.2.2 Number of determinations.6.5.2.3 Mean.6.5.2.4 Standard d

29、eviation.6.5.2.5 Observed range.6.5.2.6 Average thickness loss due to exposure.6.5.3 In the event residual coating mass determinations aredesired on partially rusted specimens, the determination shouldbe made by analyzing the stripping solution for the coatingmetal.7. Exceptions to Practice7.1 In sp

30、ecific instances there will undoubtedly be caseswhere the procedure should be expanded in certain areas. Forexample:7.1.1 Depth of deepest pit, if pitting is present.7.1.2 Average depth of ten deepest pits, if pitting is present.(See Guide G46.)7.1.3 Coating mass on each surface.7.1.4 Coating mass l

31、oss on each surface.7.2 In certain instances, lack of information or other factorsmay make it impossible or impractical to obtain data for eachpoint in the practice. Any deletions or omissions from thepractice should be noted by the experimenters with a briefexplanation of why the omission was made.

32、8. Keywords8.1 atmospheric corrosion; mass loss; metallic coatings;pittingASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity

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35、eceived a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies

36、) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 99 (2015)3