1、Designation: D3528 96 (Reapproved 2016)Standard Test Method forStrength Properties of Double Lap Shear Adhesive Joints byTension Loading1This standard is issued under the fixed designation D3528; the number immediately following the designation indicates the year oforiginal adoption or, in the case
2、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.INTRODUCTIONThe accuracy of the results of strength tests of adhesive bonds will depend on the conditions
3、 underwhich the bonding process is carried out. Unless otherwise agreed upon between the manufacturer andthe purchaser, the bonding conditions should be prescribed by the manufacturer of the adhesive. Inorder to ensure that complete information is available to the individual conducting the tests, th
4、emanufacturer of the adhesive should furnish numerical values and other specific information for eachof the following variables:(1) Surface preparation(2) Mixing directions(3) Adhesive application(4) Assembly conditions(5) Curing conditions(6) Testing conditionsArange may be prescribed for any varia
5、ble by the manufacturer of the adhesive if it can be assumedby the test operator that any arbitrarily chosen value within such a range or any combination of suchvalues for several variables will be acceptable to both the manufacturer and the purchaser of theadhesive.1. Scope1.1 This test method cove
6、rs the determination of the tensileshear strengths of adhesives for bonding metals when tested inan essentially peel-free standard specimen that develops adhe-sive stress distribution representative of that developed in atypical low-peel production-type structural joint. The repro-ducibility of the
7、strengths achieved are directly related toconformance with specified conditions of preparation andtesting.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.3 This standard does not purport to address all of thesafety concer
8、ns, 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:2A167 Specification for Stainless and Heat
9、-ResistingChromium-Nickel Steel Plate, Sheet, and Strip (With-drawn 2014)3B36/B36M Specification for Brass Plate, Sheet, Strip, AndRolled BarB152/B152M Specification for Copper Sheet, Strip, Plate,and Rolled BarB209 Specification for Aluminum and Aluminum-AlloySheet and PlateB265 Specification for T
10、itanium and Titanium Alloy Strip,Sheet, and PlateD618 Practice for Conditioning Plastics for TestingD907 Terminology of AdhesivesE4 Practices for Force Verification of Testing MachinesE122 Practice for Calculating Sample Size to Estimate, With1This test method is under the jurisdiction of ASTM Commi
11、ttee D14 onAdhesives and is the direct responsibility of Subcommittee D14.80 on MetalBonding AdhesivesCurrent edition approved May 1, 2016. Published May 2016. Originallyapproved in 1976. Last previous edition approved in 2008 as D3528 96 (2008).DOI: 10.1520/D3528-96R16.2For referenced ASTM standard
12、s, 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.3The last approved version of this historical standard is referenced onwww.astm.org.Copyri
13、ght ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1Specified Precision, the Average for a Characteristic of aLot or ProcessE171 Practice for Conditioning and Testing Flexible BarrierPackaging3. Terminology3.1 DefinitionsMany terms in this test
14、 method are definedin Terminology D907.4. Significance and Use4.1 This test method is designed to produce shear propertydata for the process control and specification of adhesives. Thistest method may also be useful for research and developmentof adhesives.4.2 Lap shear properties vary with specimen
15、 configurationpreparation, speed, and environment of testing. Consequently,where precise comparative results are desired, these factorsmust be carefully controlled and reported.5. Apparatus5.1 Testing Machine, conforming to the requirements ofPractices E4. The testing machine should be so selected t
16、hat thebreaking load of the specimens falls between 15 and 85 % ofthe full-scale capacity. The machine should be capable ofmaintaining a rate of loading of 8.27 to 9.65 MPa (1200 to1400 psi)/min, or if the rate is dependent on crosshead motion,the machine should be set to approach the rate of loadin
17、g. Itshould be provided with a suitable pair of self-aligning grips tohold the specimen. The grips and attachments should be soconstructed that they will move into alignment with the testspecimen as soon as the load is applied, so that the long axis ofthe test specimen will coincide with the directi
18、on of the appliedpull through the center line of the grip assembly.6. Test Specimen6.1 The test specimens should conform to one of thealternative types as dimensioned and shown in Fig. 1 or Fig. 2.Cut the specimens from the appropriate test panels that havebeen prepared as prescribed in Section 7. F
19、or aluminum-alloyspecimens the recommended thickness of the sheet is 3.24 60.125 mm (0.125 6 0.005 in.). The recommended test overlaplength (L) for most metals, with adherends of the prescribedmetal thickness and arranged as shown in Figs. 1 and 2, is 12.76 0.25 mm (0.5 6 0.01 in.).NOTE 1Since it is
20、 undesirable to exceed the yield point of the metalin tension during test, the permissible length of overlap in the specimenwill vary with the thickness and type of metal and on the general level ofstrength of the adhesive being investigated. The maximum permissiblelength may be computed from the fo
21、llowing relationship:L 5Fty t1and L 5Fty t22where:L = length of overlap, in., (Figs. 1 and 2),t1= thickness of doubler, in., (Figs. 1 and 2),t2= thickness of adherend in., (Figs. 1 and 2),Fty = yield point of adherend (or stress at proportional limit), psi, and = 150 % of the estimated average shear
22、 strength of the adhesivebond, psi.NOTE 2Variations in adherend thickness, and of the length of theoverlap, normally influence the test values and make direct comparison oftest data questionable. Therefore, it is preferable for the comparative orspecification tests, to standardize on the typical spe
23、cimen configurationshown with appropriate adherend gages as computed in accordance withNote 1. When specimens incorporating special lap lengths are developedfor specific studies, the adherend gage and geometry, once established,should not be altered.6.2 The following grades of metals are recommended
24、 forthe test specimens:Brass Specification B36/B36M, CDA 268Copper Specification B152/B152M, CDA 110Aluminum Specification B209, Alloy 2024, T3 TemperCorrosion-resisting steel Specification A167, Type 302, 2B FinishTitanium Specification B265, Grade 36.3 The minimum sample size necessary to develop
25、typicalor design values for a given joint geometry should be specifiedon the test request in accordance with the principles presentedT1=1.6mmT2=3.2mmA = Test GluelinesB = Spacer = T2C = Area in Test GripsD Shear AreaFIG. 1 Form and Dimensions of Type A SpecimensT1=1.6mmT2=3.2mmA = Test GluelinesB =
26、Area in Test GripsC = Shear areasFIG. 2 Form and Dimensions of Type B SpecimenD3528 96 (2016)2in Practice E122. Because of inherent variations in adhesiveproperties, due to process variables, specimens should beselected from a minimum of four different test panels.7. Test Specimens7.1 It is recommen
27、ded that the test panels be of a widthsufficient to be cut into at least five test specimens unaffectedby panel joint edge variables. Do the cutting operation in amanner that will not overheat, damage by exposure to unsat-isfactory coolants, or mechanically damage the bonded joints.Panels of two alt
28、ernative configurations are shown in Figs. 3and 4 from which the test specimens (Fig. 1 or Fig. 2) may becut. Vary the adherend sheet length to accommodate changes inbond lap length. Cut sheets of the prescribed adherend metalsto suitable size. The edges of the metal panels which will bewithin (or b
29、ound) the lap joints should be free of burrs,deformation, and bevels. The bond faying surfaces should besmooth (rms 160 max) before the panels are surface treated andbonded. Prepare the bond faying surfaces carefully in accor-dance with the procedure prescribed by the adhesive manufac-turer or the g
30、overning approved process specification andassemble with adequate spacer sheets to prevent bondlinedeformation in the lap area. Prepare and apply the adhesive inaccordance with the prescribed process specification. Theprime coat, if used, apply to a bond area faying surface insufficient width to ext
31、end beyond the lap bond area byapproximately 6 mm (0.125 in.). The adhesive, liquid or film,apply or position in the bond area limiting its extension beyondthe adherends to 1.62 6 0.25 mm (0.064 6 0.001 in.) toprevent excessive filleting. Cure the adhesive in conformancewith the prescribed process s
32、pecification.NOTE 3Bonding specimens in multiple-width panels is believed toproduce the most representative individual test specimens. Die-punchedpanels or individual specimens may be used for special studies; however,fabrication problems will be increased due to inadvertent slippage of theindividua
33、l adherends.8. Procedure8.1 Precondition the finished specimens as specified in thetest request. Conduct room temperature tests under controlledtemperature and relative humidity conditions in accordancewith Specification E171 (23 6 2C (73.4 6 3.6F) and 50 65 % relative humidity.8.2 Conduct depressed
34、 or elevated temperature tests in acontrolled chamber. The chamber should be of sufficient size toaccommodate the test grips for preconditioning and thermalstability during the test. After the test chamber and grips havebeen brought to equilibrium, place an instrumented dummyspecimen in the grips an
35、d calibrate the bondline temperaturefor each desired test condition.NOTE 4It is recommended that the dummy specimen be calibrated bythe following procedure. Instrument the specimen with two thermo-couples. Position one in the geometric center of the bondline and securethe second to the external surf
36、ace, in the geometric center of the metal laparea. Position and secure the dummy specimen in the test grips within thethermally stabilized test chamber. Record the time required for thebondline to reach the test temperature. Monitor and simultaneously recordthe temperature of the surface thermocoupl
37、e.8.3 Measure the width of the specimen and the overlaplengths of the nearest 0.25 mm (0.01 in.) to determine the shearareas.A=Predrilled Pinholes(4 required; 2.4-mm diameter)FIG. 3 Form and Dimensions of Standard Test Panel for Type ASpecimensA =Predrilled Pinholes(4 required; 2.4-mm diameter)B =Su
38、ggest TFE-fluorocarbon Filler for Adhesive Flash ControlFIG. 4 Form and Dimensions of Standard Test Panel for Type BSpecimensD3528 96 (2016)38.4 Place the specimens in the grips of the test machine sothat the terminal 31.8-mm (1.25-in.) ends are engaged firmlyand so that the long axis of the test sp
39、ecimen coincides with thedirection of the pull.8.4.1 There should be no slack in the test linkage just priorto applying a load; a preload, if used, shall not exceed 350 kPa(50 psi) during final stabilization and soak.8.4.2 Control the temperature exposure, where applicable,by the cycle determined wi
40、th the calibration. A periodic checkof the cycle may be made by attaching a thermocouple to theexternal surface of a test specimen in a manner similar to thecalibration test.8.5 The test temperature tolerance shall be in accordancewith Practice D618.8.6 Unless otherwise specified, load the test spec
41、imen tofailure at a rate of 8.27 to 9.65 MPa (1200 to 1400 psi)/min.This rate of loading will be approximated by a free crossheadspeed of 1.27 mm (0.05 in.)/min.8.7 Record the load at failure, the test temperature and soaktime, the nature and amount of failure (cohesion in theadhesive, adhesion betw
42、een adhesive and metal or metal).Failing stresses shall be expressed in kilograms per squarecentimetre (or pounds-force per square inch) of total shear area(both bond lines) calculated to the nearest 0.06 cm.2(0.01 in.2),and to the third significant figure.9. Report9.1 The report should include the
43、following:9.1.1 Complete identification of the adhesive tested, includ-ing type, form, source, manufacturers code numbers, procure-ment specification number (where applicable), weight persquare foot (square metre) at application and cured gluelinethickness,9.1.2 Complete identification of the adhere
44、nd material, theindividual adherend thicknesses and the heat treat condition(where applicable),9.1.3 Adherend preparation for bonding,9.1.4 Adhesive application and bonding conditions used inpreparation of the specimens (specification number, whereapplicable),9.1.5 Final width of specimen and length
45、 of bond overlapmeasured to the nearest 0.25 mm (0.01 in.),9.1.6 Conditioning procedures for specimens prior totesting,9.1.7 Test temperature and soak time,9.1.8 Number of specimens tested, coded for positions intest panels,9.1.9 Type of specimen and number of test panelsrepresented,9.1.10 Maximum,
46、minimum, average, and coefficient ofvariation for the stress at failure, and9.1.11 Nature of failure, including the estimated percentageof failure in cohesion and adhesion or metal failure.10. Precision and Bias10.1 A precision and bias statement does not exist for thistest method because resources
47、necessary for round-robin test-ing have not been forthcoming.11. Keywords11.1 metals; shear; tension; testingASTM 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
48、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 reviewed every five years andif not revised, either reap
49、proved 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 theresponsible 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 Conshohocken, PA 19428-2959,Un
