ASTM_F_2832_-_11.pdf

Designation:F283211Standard Guide forAccelerated Corrosion Testing for Mechanical Fasteners1This standard is issued under the fixed designation F2832;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 parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This guide covers test procedures for performing accel-erated tests to evaluate relative corrosion resistance of variouscoatings applied to mechanical fasteners.Corrosion mecha-nisms such as general and crevice corrosion may be evaluatedwith this method.Test duration may be selected to achieve anydesired level of corrosion exposure and provides a frame ofreference to determine relative coating resistance to corrosion.Fasteners tightened to a desired tension and subjected to thistest procedure may be evaluated to simulate a variety of serviceconditions.Without large amounts of accumulated field results,it is difficult to relate test duration or the number of test cyclesto actual service life for a given application.1.2 This standard is not intended to cover tests of drivenfasteners such as nails,staples,screws and lag bolts.1.3 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 limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2A480/A480M Specification for General Requirements forFlat-Rolled Stainless and Heat-Resisting Steel Plate,Sheet,and StripB117 Practice for Operating Salt Spray(Fog)ApparatusB605 Specification for Electrodeposited Coatings of Tin-Nickel AlloyD1193 Specification for Reagent WaterF1470 Practice for Fastener Sampling for Specified Me-chanical Properties and Performance InspectionF1789 Terminology for F16 Mechanical FastenersG1 Practice for Preparing,Cleaning,and Evaluating Corro-sion Test Specimens2.2 ASME Standard:3ASME B18.12 Glossary of Terms for Mechanical Fasten-ers2.3IFI Standards4IFI-170 Accelerated Corrosion Test for Mechanical Fasten-ers3.Terminology3.1 Definitions for many of the terms used in this standardare included in Terminology F1789 and ASME B18.12.3.2 Definitions of Terms Specific to This Standard:3.2.1 cyclea series of events scheduled over a 24-hourperiod3.2.2 phasea test period which has elapsed for 8 cycles.3.2.3 test durationa series of cycles as defined inSection 4.4.Test Duration4.1 Test duration is specified as A,B,C,D or E inaccordance with Table 1.4.2 A typical cycle is shown in Table 2.5.Apparatus and Materials5.1 Coupons 25.4 mm wide and 50.8 mm long having athickness selected from Table 3 shall be used.Dimensionaltolerances of Specification A480/A480M shall apply.Couponsshall have a plain finish and be manufactured from AISI1008steel grade.Coupons shall be included with fasteners to betested to verify that uniform amounts of corrosion have beenproduced by tests.Refer to Fig.1,Fig.1(a)and Fig.1(b)andTable 3.Inclusion of a metal loss coupon assists in makingcomparisons from one test to another and allows one toquantify a repeatable test.5.2 A fog humidity cabinet shall be used in which salt mistapplications are coupled with high humidity and moderatelyhigh temperature.Water fog or visible water droplets on parts1This guide is under the jurisdiction of ASTM Committee F16 on Fasteners andis the direct responsibility of Subcommittee F16.01 on Test Methods.Current edition approved Feb.1,2011.Published February 2011.DOI:10.1520/F283211.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Available from American Society of Mechanical Engineers(ASME),ASMEInternational Headquarters,Three Park Ave.,New York,NY 10016-5990,http:/www.asme.org.4Available from Industrial Fasteners Institute(IFI),6363 Oak Tree Blvd.Independence,OH 44131 http:/www.indfast.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 being tested shall be continuous after equilibrium is reached.Dry-off may be sequenced manually or automatically.5.3 Racks suitable for supporting bolt or screw assembliesshall be agreed upon between supplier and purchaser.Testresults shall always state materials used for racks duringtesting.Nylon or other suitable nonmetallic washers shall beinstalled to prevent bolt or screw heads or test coupons fromcontact with test racks.See Fig.1 and 7.8.6.Salt Mist Application and Dry-off6.1 Salt solution shall conform to requirements of Table 4.Solutions shall be sprayed by nozzles to provide a mist suchthat test fasteners and coupons are thoroughly wet and drippingwhen examined visua