1、Designation: G33 99 (Reapproved 2010)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) adequate photo-graphic, micrographic, and chemical laboratory examinationsat specific stages of deterior
4、ation, and at the end of the tests.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 limit
5、ations 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 Thick
6、ness byMagnetic-Field or Eddy-Current (Electromagnetic) Exami-nation MethodsG46 Guide for Examination and Evaluation of PittingCorrosion3. 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 compari
7、ng 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,
8、 elec-troless, 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)
9、 Metallurgical 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 Coati
10、ng Weight 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) Mea
11、n,(4) 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.1This practice is under the jurisdiction of ASTM Committee G01 on Co
12、rrosionof Metals and is the direct responsibility of Subcommittee G01.04 on AtmosphericCorrosion.Current edition approved May 1, 2010. Published May 2010. Originallyapproved in 1972. Last previous edition approved in 2004 as G3399(2004). DOI:10.1520/G0033-99R10.2For referenced ASTM standards, visit
13、the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959
14、, United States.4.2.4 Direction of specimen faces.4.2.5 Location of test area.4.2.6 Description of test area (location of nearby industry,ocean, and so forth, and recorded data on specific contaminantswhere possible).4.2.7 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 specular reflectivity,(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 powdery surfacelayer 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
21、terms 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) CrackingAn
22、y 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 corrosion prod-ucts,(7)
23、NodulesLittle 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
24、of 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, sun-shine, rain, and so forth).6.2.3 Removal date.6.2.4 Exposure time in years (fractions as decimals tonearest tent
25、h).6.3 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 coa
26、ting 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)
27、.6.5 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) us
28、ingabove 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.6.5.2.2 Number of determinations.6.5.2.3 Mean.G33 99 (2010)26.5.2.4 Stand
29、ard deviation.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
30、In specific 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 m
31、ass loss 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
32、made.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 vali
33、dity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comm
34、ents are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have
35、not received 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 c
36、opies) 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 ASTM website (www.astm.org/COPYRIGHT/).G33 99 (2010)3
