1、Designation: D 3528 96 (Reapproved 2002)Standard Test Method forStrength Properties of Double Lap Shear Adhesive Joints byTension Loading1This standard is issued under the fixed designation D 3528; the number immediately following the designation indicates the year oforiginal adoption or, in the cas
2、e of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) 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 conditi
3、ons 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,
4、 themanufacturer 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 conditionsA range may be prescribed for any v
5、ariable 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
6、covers 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
7、the 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 co
8、ncerns, 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:A 167 Specification for Stainless and
9、Heat-ResistingChromium-Nickel Steel Plate, Sheet, and Strip2B 36 Specification for Brass Plate, Sheet, Strip, and RolledBar3B 152 Specification for Copper Sheet, Strip, Plate, andRolled Bar3B 209 Specification for Aluminum and Aluminum-AlloySheet and Plate4B 265 Specification for Titanium and Titani
10、um Alloy Strip,Sheet, and Plate5D 618 Practice for Conditioning Plastics for Testing6D 907 Terminology of Adhesives7E 4 Practices for Force Verification of Testing Machines81This test method is under the jurisdiction of ASTM Committee D14 onAdhesives and is the direct responsibility of Subcommittee
11、D14.80 on MetalBonding Adhesives.Current edition approved Sept. 10, 1996. Published November 1996. Originallypublished as D 3528 76. Last previous edition D 3528 92.2Annual Book of ASTM Standards, Vol 01.03.3Annual Book of ASTM Standards, Vol 02.01.4Annual Book of ASTM Standards, Vol 02.02.5Annual B
12、ook of ASTM Standards, Vol 02.04.6Annual Book of ASTM Standards, Vol 08.01.7Annual Book of ASTM Standards, Vol 15.06.8Annual Book of ASTM Standards, Vol 03.01.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.E 122 Practice for Calcula
13、ting Sample Size, With a Speci-fied Tolerable Error, the Average for a Characteristic of aLot or Process9E 171 Specification for Standard Atmospheres for Condi-tioning and Testing Flexible Barrier Materials103. Terminology3.1 DefinitionsMany terms in this test method are definedin Terminology D 907.
14、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 configurationpreparation, speed, and e
15、nvironment 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 E 4. The testing machine should be so selected thatthe breaking load of the specimens
16、falls between 15 and 85 %of the 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 loading. Itshould be provided with a suitabl
17、e 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 direction of the appliedpull through the cent
18、er 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. For aluminum-alloyspecimens the recomme
19、nded 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 undesirable to exceed the yield point
20、 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 following relationship:L 5Fty t1tand L 5
21、Fty 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,andt = 150 % of the estimated average shear strength of the adhesivebond, psi.NO
22、TE 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 specimen configurationshown with appropr
23、iate 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 forthe test specimens:9Annual Book o
24、f ASTM Standards, Vol 14.02.10Annual Book of ASTM Standards, Vol 15.09.T1= 1.6 mmT2= 3.2 mmA = Test GluelinesB = Spacer = T2C = Area in Test GripsD Shear AreaFIG. 1 Form and Dimensions of Type A SpecimensT1= 1.6 mmT2= 3.2 mmA = Test GluelinesB = Area in Test GripsC = Shear areasFIG. 2 Form and Dimen
25、sions of Type B SpecimenD 3528 96 (2002)2Brass Specification B 36, CDA 268Copper Specification B 152, CDA 110Aluminum Specification B 209, Alloy 2024, T3 TemperCorrosion-resisting steel Specification A 167, Type 302, 2B FinishTitanium Specification B 265, Grade 36.3 The minimum sample size necessary
26、 to develop typicalor design values for a given joint geometry should be specifiedon the test request in accordance with the principles presentedin Practice E 122. Because of inherent variations in adhesiveproperties, due to process variables, specimens should beselected from a minimum of four diffe
27、rent test panels.7. Test Specimens7.1 It is recommended 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 mec
28、hanically damage the bonded joints.Panels of two alternative 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
29、 edges of the metal panels which will bewithin (or bound) 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 procedu
30、re prescribed by the adhesive manufac-turer or the governing 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
31、a bond area faying surface insufficient width to extend 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
32、adhesive in conformancewith the prescribed process specification.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 i
33、ncreased due to inadvertent slippage of theindividual 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 E 171 (23 6 2C (73.4 6 3.6F
34、) and 50 65 % relative humidity.8.2 Conduct depressed 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
35、, place an instrumented dummyspecimen in the grips and 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 t
36、he bondline and securethe second to the external surface, 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 simultaneo
37、usly recordthe temperature of the surface thermocouple.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 =Suggest TFE-fluorocarbon Filler for Adhesive Flash ControlFIG. 4 Form
38、and Dimensions of Standard Test Panel for Type BSpecimensD 3528 96 (2002)38.3 Measure the width of the specimen and the overlaplengths of the nearest 0.25 mm (0.01 in.) to determine the shearareas.8.4 Place the specimens in the grips of the test machine sothat the terminal 31.8-mm (1.25-in.) ends ar
39、e engaged firmlyand so that the long axis of the test specimen 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 temperatu
40、re exposure, where applicable,by the cycle determined with 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
41、 D 618.8.6 Unless otherwise specified, load the test specimen 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
42、amount of failure (cohesion in theadhesive, adhesion between 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 signi
43、ficant figure.9. Report9.1 The report should include the 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 glue
44、linethickness,9.1.2 Complete identification of the adherend 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,
45、whereapplicable),9.1.5 Final width of specimen and length of bond overlapmeasured to the nearest 0.25 mm (0.01 in.),9.1.6 Conditioning procedures for specimens prior to test-ing,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 spe
46、cimen and number of test panels repre-sented,9.1.10 Maximum, 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 st
47、atement does not exist for thistest method because resources 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
48、 this standard. 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 mus
49、t be reviewed 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 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 Harb
