1、Designation: D 5041 98 (Reapproved 2004)Standard Test Method forFracture Strength in Cleavage of Adhesives in BondedJoints1This standard is issued under the fixed designation D 5041; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision,
2、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.1. Scope1.1 This test method covers the determination of fracturestrength in cleavage of adhesive bonds when tested o
3、n standardreinforced plastic specimens and under specified conditions ofpreparation and testing (Note 1).NOTE 1While this test method is intended for use in reinforced plasticapplications, it may be used for measuring fracture properties of adhesivesusing other plastic adherends, provided considerat
4、ion is given to thethickness and should be of equal rigidity to the plastic adherends.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 concerns, if any, associat
5、ed 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:2D 618 Practice for Conditioning Plastics for TestingD 907 Ter
6、minology of AdhesivesD 2093 Practice for Preparation of Surfaces of Plastics Priorto Adhesive BondingD 5573 Practice for Classifying Failure Modes in Fiber-Reinforced-Plastic (FRP) JointsE 4 Practices for Force Verification of Testing Machines3. Terminology3.1 DefinitionsMany of the terms used in th
7、is test methodare defined in Terminology D 907.3.2 Definitions of Terms Specific to This Standard:3.2.1 failure initiation energy, Eithe area under the loaddeflection curve where the first significant load drop occursafter the start of the test, showing the onset of permanentdamage to the bonded ass
8、embly (see Fig. 1).3.2.2 failure propagation energy, Epthe area under theload-deflection curve beginning at the failure initiation energyand ending at the catastrophic failure of the bonded assembly.(See Fig. 1).3.2.3 semirigidindicates that the adherends shall havesuch dimensions and physical prope
9、rties as to permit bendingthem through any angle of up to 30 without breaking orcracking.3.2.4 semirigid adherend, nan adherend that has dimen-sions and physical properties that permit bending at designatedtest temperature through any angle up to 30 without breakingor cracking.3.2.5 total energyfail
10、ure initiation energy plus failurepropagation energy.4. Significance and Use4.1 This test method provides a means of measuring thecleavage forces and energies required to fail adhesively bondedreinforced flat bonded specimens. It also offers a semi-quantitative observation of failure mode.4.2 This t
11、est method has found application in screeningstructural adhesives for bonding reinforced plastics wheresimple lap shear testing has proven to be inadequate indistinguishing differences between adhesives.4.3 It is important to note that the test method measuresperformance properties of the total bond
12、ed system (for ex-ample, reinforced plastic and adhesive) but will not yieldfundamental properties of the adhesive alone.5. Apparatus5.1 Testing Machine, any suitable testing machine capableof control of constant-rate-of-crosshead movement and com-prising essentially the following:5.1.1 Drive Mechan
13、ism, a mechanism for imparting to thecross-head movable member, a uniform, controlled velocitywith respect to the base (fixed member); this velocity is to beregulated as specified in Section 10.5.1.2 Load Indicator, a mechanism capable of showing thetotal compressive load carried by the test specime
14、n. Themechanism is to be essentially free from inertia-lag at thespecified rate of testing and indicate the load with an accuracy1This test method is under the jurisdiction of ASTM Committee D14 onAdhesives and is the direct responsibility of Subcommittee D14.40 on Adhesives forPlastics.Current edit
15、ion approved April 1, 2004. Published April 2004. Originallyapproved in 1990. Last previous edition approved in 1998 as D 5041 98.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume informat
16、ion, 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.of 61 % of the maximum indicated value of the test (load).Verify the accuracy of the testing machine at least once a
17、 yearin accordance with Practices E 4.5.2 Wedge, made of either aluminum or steel with anincluded angle of 45. The sides of the wedge are machinedsmooth with the edge having a radius not to exceed 0.02 mm(0.01 in).NOTE 2A stainless steel wedge is recommended, has been found towork well, and is very
18、durable. Due to the weight of a steel wedge, theremoval of excess metal, which does not adversely affect the stiffness ofthe wedge, is recommended.5.3 Removable Tip (Optional)In some cases, the tip of thetraveling wedge will strike the adhesive before catastrophicfailure. This phenomenon will lead t
19、o grossly distorted testdata. Should this be a problem in some adhesively bondedassemblies, a removable tip wedge of the design shown in Fig.2 is suggested.5.4 Support Fixture, an adjustable fixture used to supportand center the bonded assembly under the tip of the wedge. SeeFig. 3.5.5 Integrator, a
20、 mechanical or electronic device or com-puter for the determination of failure energies.5.6 Bond Fixture, any suitable fixture with temperature- andpressure-controlled platens, capable of bonding test assembliesin accordance with the adhesive manufacturers recommenda-tions.6. Test Assemblies6.1 Flat
21、 Adherend, unless otherwise specified in materialspecifications, make the test adherends in conformance to theform and dimensions shown in Fig. 4. Cut them from flatsemirigid plastic panels having a nominal thickness of 2.54mm (0.1 in.) 6 0.5 %. Cut adherends into sections, 150 by 150mm (6 by 6 in.)
22、, 6 0.5 %. (See appendix for optional specimensizes.)FIG. 1 A Typical Load versus Deflection Curve for Wedge TestFIG. 2 Wedge with Removable TipFIG. 3 Test SetupFIG. 4 Placement of Adhesive BeadD 5041 98 (2004)27. Preparation7.1 Laminated test assemblies (Fig. 5) consist of twoadherends of similar s
23、tiffness properly prepared and bondedtogether.NOTE 3If the bonded test assembly is constructed with adherends ofdifferent stiffness, the result is a peel rather than a cleavage test. (Forexample, higher stiffness promotes cleavage; lower stiffness, peel.)7.2 Prepare the surface of the substrate prio
24、r to bonding inaccordance with the adhesive suppliers recommendations.Typical surface preparations include solvent scrubbing, appli-cation of primers and, in some cases, only a dry rag wipe.NOTE 4It is important to be aware of potential substrate surfacedifferences. Frequently reinforced plastics ha
25、ve a preferred bonding side.Contact the substrate supplier if there is any doubt.7.3 Prepare and dispense the adhesive in accordance withadhesive manufacturers recommendations, or as specified oragreed upon between the buyer and the seller.7.4 An adhesive bead is applied to the center of the bondare
26、a across the full width of the adherend (see Fig. 4). Thebondline thickness and flow are controlled by a combination ofshims and glass beads. Apply a uniform light coating of0.76-mm (0.03-in.) glass beads onto the adhesive and positionTFE-fluorocarbon or release coated steel shim, as shown, tocontro
27、l final adhesive thickness.7.5 Mate the two halves of the cleavage assembly as soon aspossible after applying the glass beads to form the testassembly shown in Fig. 5. The entire bonded assembly may bewrapped in aluminum foil to protect the heated platens used tocure the adhesive. Cure the adhesive
28、in accordance with theadhesive suppliers recommendation. Immediately after cur-ing, remove the shims from the bonded assemblies and trim theadhesive squeeze-out. Allow the bonded assemblies to cool andthen condition at 23 6 2C (73.4 6 3.6F) for 24 h and 50 64 % relative humidity prior to postbaking
29、or testing.7.6 Postbake assemblies (as required) as experienced inend-use (production) or in accordance with the adhesivemanufacturers recommendation.8. Number of Test Specimens8.1 Test at least five specimens for each condition (forexample, adhesive, adherend, or specimen preconditioning).8.2 Disca
30、rd specimens that break at some obvious flaw andmake retests, unless such flaws constitute a variable to bestudied.9. Conditioning9.1 Conditioning Condition the test specimens at 23 62C (73.4 6 3.6F) and 506 5 % relative humidity for not lessthan 14 h prior to test in accordance with Procedure A ofP
31、ractice D 618 for those tests where conditioning is required.In cases of disagreement, the tolerances shall be 61C(61.8F) and 62 % relative humidity.9.2 Test Conditions Conduct tests in the standard labora-tory atmosphere of 23 6 2C (73.4 6 3.6F) and 50 6 5%relative humidity, unless otherwise specif
32、ied. In cases ofdisagreement, the tolerances shall be 61C (61.8F) and62 % relative humidity.10. Speed of Testing10.1 Speed of testing is the relative rate of motion of the testfixtures during the test. Rate of motion of the driven fixture,when the machine is running idle, may be used if it can besho
33、wn that the resulting speed of testing is within the limits ofvariation allowed.10.2 The standard speed of testing is 127 6 0.5 mm/min(5.0 in./min),10.3 The standard chart speed is 250 mm/min (10.0 in./min).NOTE 5Direct comparisons of different adhesives can be made onlywhen specimen construction an
34、d test conditions are identical.NOTE 6Within the limitations imposed by Note 5 other specimenwidths may be used, (see appendix) provided the test machine is capableof applying the load uniformly across the width of the adherends.11. Procedure11.1 Rigidly fix the wedge and support fixture in the test
35、ingmachine so that the bonded assembly is vertically alignedbetween the wedge and support fixture as shown in Fig. 3. Theslot in the support fixture must be adjusted to allow fordeflection of the adherends and must be at least 0.125 in.greater than the thickness of the test assembly.11.2 Set speed c
36、ontrol to 127 mm/min (5 in./min).11.3 Set the chart speed to 250 mm/min (10 in./min).11.4 Set electronic data gathering instrumentation to auto-matically record the complete load-deformation curve.11.5 Apply compressive load to the bonded assembly at thespecified rate and plot the load-deformation c
37、urve.11.6 When the wedge has penetrated beyond the removabletip, gently remove the tip from the wedge as the test continuesuntil the assembly fails (optional).11.7 Two areas of interest on the load-deformation curve arefailure initiation and failure propagation. The first load dropalong the curve sh
38、ows the onset of permanent damage and isreferred to as the failure initiation point. Since this point issometimes hard to identify, for consistency between laborato-ries, the first significant drop in load is normally used for thefailure initiation point (see Fig. 1).FIG. 5 Test SpecimenD 5041 98 (2
39、004)311.7.1 The failure propagation area begins at the failureinitiation point and continues until catastrophic failure of thetest assembly. During this time energy is being absorbed by thebonded assembly as the wedge separates the two adherends.12. Calculation12.1 In the absence of electronics inst
40、rumentation, calculatethe failure initiation energy and failure propagation energy bydetermining the area under the load-deformation curve.12.2 For the test parameters specified in this test method, theenergy/in.2of the chart, beneath the curve, is 0.5 mm/min (5.0in.lb/in.2) Energy for subdivisions
41、is determined by the gridsize.13. Report13.1 Report the following information:13.1.1 Complete identification of the adhesive tested, in-cluding type, source, manufacturer code number, batch or lotnumber, form, etc.13.1.2 Complete identification of adherends used, includingmaterial, thickness, surfac
42、e preparation, and orientation.13.1.3 Description of bonding process, including method ofapplication of adhesive, glue-line thickness, drying or precur-ing conditions (where applicable), curing time, temperature,and pressure.13.1.4 Average thickness of adhesive layer after formationof the joint, wit
43、hin 0.025 mm (0.001 in.). Describe the methodof obtaining the thickness of the adhesive layer includingprocedure, location of measurement, and range of measure-ments.13.1.5 Complete description of test specimens, includingdimensions and construction of test assemblies conditions usedfor cutting indi
44、vidual test adherends, number of test panelsrepresented, and number of individual test assemblies.13.1.6 Conditioning procedure used for assemblies prior totesting including any post-bake conditions.13.1.7 Type of test machine and crosshead rate and chartspeed used.13.1.8 Environmental test conditio
45、ns.13.1.9 Type of failure for each individual specimen. Forfiber-reinforced-plastic (FRP) adherends such as sheet moldingcompound (SMC), evaluate failure in accordance with PracticeD 5573.13.1.10 Failure initiation energy and failure propagationenergy.14. Precision and Bias14.1 Table 1 lists data ge
46、nerated at six different laboratoriesusing a single adhesive, a standard FRP and individual labo-ratory test apparatus. All bonding was done in Laboratory No.2 with bonded parts sent to other laboratories. Raw data is onfile at ASTM International Headquarters.15. Keywords15.1 adhesive; cleavage; fib
47、er-reinforced-plastic; wedgeAPPENDIX(Nonmandatory Information)X1. OPTIONAL SPECIMEN SIZESX1.1 In many cases it is desirable to test parts smaller than150 by 150 mm (6 by 6 in.). This need could arise from limitedavailability of substrate, limited access to sufficiently large flatsurfaces or real par
48、ts, etc. Consequently, reduced size partsmay sometimes be tested. Provided test part size is not reducedto less than 50 by 150 mm (2 by 6 in.), the graph (Fig. X1.1),shown below, illustrates that energy measurements are linearover various part sizes with 50-mm (2-in.) wide bond areas.X1.2 For proper
49、 interpolation of energies, the slope of theline should be determined since it has been established that therelationship is linear (Fig. X1.1 and Fig. X1.2).TABLE 1 Round-Robin Data Conducted at Six LaboratoriesLaboratoryFiberTear, %PeakLoad, lbTotalEnergy, in.lbIn.lb Energy at 1-in. Intervals1 in. 2 in. 3 in. 4 in. Break1 95 44.6 116.0 12.1 40.6 75.2 108.7 116.02 100 41.6 110.7 12.7 43.0 76.6 110.8 110.73 80 41.8 109.6 . . . . 109.64 94 46.6 111.2 11.6 42.3 74.6 76.3 111.35 100 44.8 118.3 14.6 45.6 . 77.7 117.16 96 39.5 120.8 15.7 51.0 87.0 120.
