1、Designation: F2833 11Standard Specification forCorrosion Protective Fastener Coatings with Zinc Rich BaseCoat and Aluminum Organic/Inorganic Type1This standard is issued under the fixed designation F2833; the number immediately following the designation indicates the year oforiginal adoption or, in
2、the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification covers the basic requirements forchromium-free fastener coatings
3、that combine an inorganiczinc-rich basecoat with an aluminum-rich topcoat that containsan integrated lubricant.1.2 These coatings are applied by conventional dip-spin,dip-drain, or spray methods to ferrous parts which can behandled through a cleaning, or phosphate, coating, and bakingoperation. Phos
4、phating or shot blast is required to clean andprepare the surface of the steel. These coatings are bake curedat temperatures up to 500F.NOTE 1If used, phosphate to be used in accordance with SpecificationF1137, grade 0.1.3 UnitsThe values stated in inch-pound units are to beregarded as standard. No
5、other units of measurement areincluded in this standard.1.4 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-bilit
6、y of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2B117 Practice for Operating Salt Spray (Fog) ApparatusD610 Practice for Evaluating Degree of Rusting on PaintedSteel SurfacesD3359 Test Methods for Measuring Adhesion by Tape TestF606 Test Methods for Determining the
7、 Mechanical Prop-erties of Externally and Internally Threaded Fasteners,Washers, Direct Tension Indicators, and RivetsF606M Test Methods for Determining the MechanicalProperties of Externally and Internally Threaded Fasteners,Washers, and Rivets (Metric)F1137 Specification for Phosphate/Oil and Phos
8、phate/Organic Corrosion Protective Coatings for FastenersF1470 Practice for Fastener Sampling for Specified Me-chanical Properties and Performance InspectionF1624 Test Method for Measurement of Hydrogen Em-brittlement Threshold in Steel by the Incremental StepLoading TechniqueF1789 Terminology for F
9、16 Mechanical FastenersF1940 Test Method for Process Control Verification toPrevent Hydrogen Embrittlement in Plated or CoatedFasteners3. Classification3.1 When the zinc phosphate option is used, its coatingweight shall be in the range of 8-20 g/square meter. If used,phosphate to be used in accordan
10、ce to Specification F1137grade 0.3.2 These coatings are classified into 5 different types:3.2.1 Grade 1requires a minimum basecoat thickness of0.27 mils applied in one coat. An organic topcoat with anintegrated lubricant is applied at a minimum thickness of 0.20mils in one coat and; with no addition
11、al layers.3.2.2 Grade 2requires a minimum basecoat thickness of0.27 mils applied in two coats bulk or one coat sprayed. Anorganic topcoat with an integrated lubricant is applied at aminimum thickness of 0.20 mils in one coat; with no additionallayers.3.2.3 Grade 3requires a minimum basecoat thicknes
12、s of0.27 mils applied in one coat. This basecoat is dark gray incolor. A black organic topcoat with an integrated lubricant isapplied at a minimum thickness of 0.20 mils in two coats bulkor one coat sprayed; with no additional layers.3.2.4 Grade 4 requires a minimum basecoat thickness of0.27 mils ap
13、plied in one coat. An inorganic topcoat with anintegrated lubricant is applied at a minimum thickness of 0.20mils and an integrated lubricant in one coat; with no additionallayers.1This specification is under the jurisdiction of ASTM Committee F16 onFasteners and is the direct responsibility of Subc
14、ommittee F16.03 on Coatings onFasteners.Current edition approved Feb. 1, 2011. Published February 2011. DOI: 10.1520/F283311.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information,
15、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, United States.3.2.5 Grade 5requires a minimum basecoat thickness of0.27 mils applied in one coat. An organic pigmented topcoatwith an i
16、ntegrated lubricant is applied at a minimum thicknessof 0.20 mils in one coat for additional corrosion protection withno additional layers.4. Ordering Information4.1 Orders for material in accordance with this specificationshall include the following information:4.1.1 Quantity of parts,4.1.2 Color o
17、f coating,4.1.3 Grade of coating (see Table 1),4.1.4 Any additions to specifications as agreed upon by thepurchaser and the supplier, and4.1.5 Certification and test report requirements.5. Performance Requirements5.1 AppearanceThe coating shall have a uniform appear-ance free from tears and other di
18、scontinuities which may affectthe appearance or performance, or both, of the coating.5.2 AdhesionWhen practical, the coating shall show lessthan 5 % removal following the tape adhesion test in 6.3. Dueto the nature of the coating, some removal is expected, butremoval of the coating that exposes the
19、substrate indicates pooradhesion and is cause for rejection.5.3 Corrosion ResistanceThe coating shall be capable ofwithstanding exposure to salt spray test (SST) for the minimumhours (h) specified in Table 1. Unless otherwise defined,acceptable corrosion resistance shall be Rust Grade 6 or higher(se
20、e Test Method D610 for definition) on significant surfaces(see Terminology F1789 for definition).5.4 BlistersThere shall be no signs of blisters after testingin accordance with 6.1.5.5 Thread FitThe coating shall not have an adverseeffect on normal installation and removal practices as deter-mined b
21、y the proper GO thread gauge.5.5.1 The thickness of the coating is limited by the basicthread size (3A GO gauge for external threads 6h for metricproduct, 2B GO gauge for internal threads, 6H for metricproduct). Where greater thickness is necessary, the internalthreads may be produced oversized (bef
22、ore coating) providingthe finished product (after coating) meets all the specifiedmechanical properties. Where mechanical properties are notspecified, oversizing is subject to the approval of the purchaser.6. Test Methods6.1 CorrosionCorrosion resistance shall be tested in ac-cordance with Practice
23、B117 followed by Test Method D610 torate the amount of corrosion.6.2 Coating ThicknessThe coating thickness shall bedetermined by magnetic induction, X-ray fluorescence spec-troscopy, microscopic examination of a cross-section takenperpendicular to the significant surfaces, or weigh-strip-weighmetho
24、d. When using magnetic induction, or X-ray fluores-cence, an average of ten measurements on the flat surface ofone part shall be used.NOTE 2The weigh-strip-weigh method involves weighing the testspecimen before and after the coating is stripped. The method requires areagent that does not attack the
25、base metal (for example, 20 % NaOH).6.3 AdhesionWhere practical, adhesion of the coatingshall be tested in accordance with Test Methods D3359Scribe-Grid Test. Determination if base material is exposedmay be done by visually inspecting the part, or exposing thepart to salt spray test (see Practice B1
26、17) for 96 h andobserving if red rust occurs.6.4 Hydrogen EmbrittlementWhen specified in the pur-chase order, testing shall be conducted in accordance with TestMethods F606,orF1940. (See also, Test Methods F606M.)6.4.1 In the event that hardness reductions occur in testspecimens due to coating curin
27、g times and temperatures,testing per shall be conducted alternatively in accordance withF1624.7. Sampling7.1 Sampling for testing shall be conducted based on lot sizein accordance with Practice F1470.8. Rejection and Rehearing8.1 Materials that fail to conform to the requirements of thisspecificatio
28、n shall be rejected.9. Keywords9.1 aluminum; chromium; coating; corrosion; dip spin;fasteners; protection; resistance; rust; sealer; zincTABLE 1 Coating PropertiesGrade TopcoattypeTotal number ofcoating layersAverage CoatingThickness (mil)Average CoatingWeight (g/m3)Minimum SSThrs1 Organic 2 0.470.5
29、9 3240 8402 Organic 3 0.470.71 3251 12003 Organic/black 3 0.470.71 3741 8404 Inorganic 2 0.470.59 3441 10005 Organic/various colors 2 0.470.59 3239 840F2833 112ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this stan
30、dard. Users of this standard are expressly advised that determination of the validity 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 revie
31、wed every five years andif not revised, either reapproved or withdrawn. Your comments 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 theresponsibl
32、e technical committee, which you may attend. If you feel that your comments have 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 Con
33、shohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) 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/).F2833 113
