ASTM_D_2293_-_96_2008.pdf

Designation:D229396(Reapproved 2008)Standard Test Method forCreep Properties of Adhesives in Shear by CompressionLoading(Metal-to-Metal)1This standard is issued under the fixed designation D2293;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 test method covers the determination of the creepproperties of adhesives for bonding metals when tested on astandard specimen and subjected to certain conditions oftemperature and compressive stress in a spring-loaded testingapparatus.1.2 The values stated in SI units are to be regarded asstandard.The inch-pound units in parentheses are for informa-tion only.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:2D907 Terminology of AdhesivesD1002 Test Method for Apparent Shear Strength of Single-Lap-Joint Adhesively Bonded Metal Specimens by Ten-sion Loading(Metal-to-Metal)3.Terminology3.1 DefinitionsMany terms in this test method are definedin Terminology D907.4.Significance and Use4.1 This test method is useful in research and developmentfor comparison of creep properties of adhesives,particularly asthose properties are affected by changes in adhesive formula-tion or expected service conditions,including temperature,moisture level,and duration of loading.4.2 The relative size and simplicity of design of the spring-loaded apparatus permits easy portability and transfer from oneenvironment to the next without disturbing static loads.4.3 The relative simplicity of design with inexpensivematerials permits replication of creep tests at relatively lowcosts.5.Apparatus5.1 Compression Creep Test Apparatus,as shown in Fig.1and Fig.2.5.2 Microscope,calibrated,with Filar microeyepiece and10 objective lens.6.Test Specimens6.1 Test specimens shall conform to the form and dimen-sions shown in Fig.3.These specimens are similar to thetension lap shear specimens described in Test Method D1002,except that the length of either side of the shear area shall be6.35 mm(14in.)rather than 88.9-mm(312-in.)minimum.6.2 A complete description of these specimens and themethod of preparation is given in Sections 6,7,and 8 of TestMethod D1002.6.3 For creep measurements,polish the edges of the bondedarea of each test specimen,and scribe with three fine linesacross the bondline.7.Procedure7.1 To conduct a creep test,center the specimen within theslot between the washer and bushing of the apparatus as shownin Fig.1.Compress the spring between the two bushings to thedesired load by tightening the nut.The correct load can beapplied by deflecting the spring a given measured amount asdetermined from a calibration curve.7.2 To measure total deflection,observe the average dis-placement of fine razor scratches across the centers of bothsides of the lap joints with a calibrated microscope having aFilar microeyepiece and a 10 objective lens.7.3 If the spring load is allowed to continue to compress thespecimen,the observed initial deflection will be followed by acontinued increasing deflection with time.To provide a com-plete history of creep behavior,measure these deflections1This test method is under the jurisdiction of ASTM Committee D14 onAdhesives and is the direct responsibility of Subcommittee D14.80 on MetalBonding Adhesives.Current edition approved April 1,2008.Published April 2008.Originallyapproved in 1964.Last previous edition approved in 2002 as D2293 96(2002).DOI:10.1520/D2293-96R08.2For 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 periodically with the calibrated microscope for as long as thetest is allowed to continue or until the adhesive joint fails.7.4 If a creep curve at other than room temperature isrequired,perform both the specimen loading and its subsequentexposure while holding the specimen to the desired tempera-ture.A suitable oven or cold box may be used for this purpose.Under these conditions,the actual creep measurements aremore difficult to obtain.This can be done,however,in one oftwo ways.The microscopic measurements can be madequickly and the specimen and its apparatus returned to itstemperature box before its test temperature has changedappreciably.Or,periodically,additional fine scribe lines can beadded adjacent to the original scratches across the centers ofboth sides