1、Designation: D3846 08 (Reapproved 2015)Standard Test Method forIn-Plane Shear Strength of Reinforced Plastics1This standard is issued under the fixed designation D3846; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of la
2、st revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope1.1 This test method covers the determ
3、ination of the in-plane shear strength of reinforced thermosetting plastics in flatsheet form in thicknesses ranging from 2.54 to 6.60 mm (0.100to 0.260 in.). This protocol in not for reinforced pultrudedthermoset products, which may use Test Method D2344/D2344M.1.2 The values stated in SI units are
4、 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, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices
5、 and determine the applica-bility of regulatory limitations prior to use.NOTE 1There is no known ISO equivalent to this standard.2. Referenced Documents2.1 ASTM Standards:2D618 Practice for Conditioning Plastics for TestingD695 Test Method for Compressive Properties of RigidPlasticsD2344/D2344M Test
6、 Method for Short-Beam Strength ofPolymer Matrix Composite Materials andTheir LaminatesE4 Practices for Force Verification of Testing MachinesE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3. Terminology3.1 Definitions:3.1.1 in-plane shear strengththe
7、 shear strength at rupturein which the plane of fracture is located along the longitudinalaxis of the specimen between two centrally located notchesmachined halfway through its thickness on opposing faces.4. Summary of Test Method4.1 In-plane shear strength, as determined by this testmethod, is meas
8、ured by applying a compressive load to anotched specimen of uniform width. The specimen is loadededgewise in a supporting jig of the same description as thatreferenced in Test Method D695 for testing thin specimens. Aschematic of the specimen used for this test and the supportingjig is shown in Fig.
9、 1. Failure of the specimen occurs in shearbetween two centrally located notches machined halfwaythrough its thickness and spaced a fixed distance apart onopposing faces.5. Significance and Use5.1 Shear tests of various kinds are widely used in thereinforced plastics industry to assess the strength
10、of thereinforcement-to-resin bond in polyester-, vinyl ester-, andepoxy-resin composites. In addition to their importance for thegeneration of data for research and development, qualitycontrol, and specification purposes, such tests are of fundamen-tal value to the fibrous reinforcement industry, si
11、nce they canbe used to assess the potential of new sizing systems for thesurface treatment of glass fibers.5.2 This test method is useful for establishing the shearstrength of laminates or other reinforced plastics havingrandomly dispersed fiber reinforcement. While the test alsolends itself to para
12、llel-fiber reinforced plastics, it has beendesigned to accommodate nonparallel-fiber reinforced materi-als that cannot be tested satisfactorily by the short-beamprocedure described in Test Method D2344/D2344M.6. Apparatus6.1 Testing MachineAny suitable testing machine capableof control of constant-r
13、ate-of-crosshead movement and com-prising essentially the following:6.1.1 Drive MechanismA drive mechanism for impartingto the movable member a uniform, controlled velocity withrespect to the stationary member, as required in 10.3.6.1.2 Load IndicatorA load-indicating mechanism ca-pable of showing t
14、he total compressive load carried by the test1This test method is under the jurisdiction ofASTM Committee D20 on Plasticsand is the direct responsibility of Subcommittee D20.18 on Reinforced Thermoset-ting Plastics.Current edition approved Sept. 1, 2015. Published September 2015. Originallyapproved
15、in 1979. Last previous edition approved in 2008 as D3846 - 08. DOI:10.1520/D3846-08R15.2For 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 Summar
16、y page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1specimen. The mechanism shall be essentially free of inertiallag at the specified rate of testing and shall indicate the loadwith an accuracy of 61 % of the max
17、imum indicated value ofthe test (load). The accuracy of the testing machine shall beverified at least once a year in accordance with Practices E4.6.1.3 Compression ToolA compression tool for applyingthe load to the test specimen, such as those shown in Figs. 1and 2 of Test Method D695.6.1.4 Supporti
18、ng JigA supporting jig, shown schemati-cally in Fig. 1, and conforming to the dimensions of that shownin Fig. 4 of Test Method D695.6.1.5 MicrometersSuitable micrometers, reading to 0.025mm (0.001 in.) for measuring the width and thickness of thespecimens, as well as the depth of, and distance betwe
19、en, thenotches.6.1.6 Torque WrenchAsuitable torque wrench for tighten-ing the nuts of the supporting jig of 6.1.4 to the torqueprescribed in 10.2.7. Test Specimens7.1 ConfigurationTest specimens shall conform to theshape and dimensions given in Fig. 1. The edges of thespecimens shall be smooth, but
20、not rounded or beveled.7.2 PreparationTwo parallel cuts, one on each oppositeface of the specimen and 6.4 mm (0.25 in.) apart, shall besawed across the entire width of the specimen and centrallylocated along its length. The width and depth of notch shallconform to the dimensions shown in Fig. 1. For
21、 laminatedmaterials, the notch shall be of sufficient depth to sever thecenter ply of the reinforcement, located midway between thetwo faces of the laminate.7.3 NumberFive specimens shall be tested whenever iso-tropic materials are under test. When testing material that issuspected or known to be an
22、isotropic, ten specimens (fivenormal to and five parallel with the principal axis of anisot-ropy) shall be tested.8. Conditioning8.1 ConditioningCondition the test specimens at 23 62C (73.4 6 3.6F) and 50 6 5 % relative humidity for not lessthan 40 h prior to test in accordance with Procedure A ofPr
23、actice D618, for those tests where conditioning is required.In case of disagreement, the tolerances shall be 61C (61.8F)and 62 % relative humidity.8.2 Test ConditionsConduct tests in the standard labora-tory atmosphere of 23 6 2C (73.4 6 3.6F) and 50 6 5%relative humidity, unless otherwise specified
24、. In cases ofdisagreement, the tolerances shall be 61C (61.8F) and62 % relative humidity.9. Speed of Testing9.1 Speed of testing shall be the relative rate of motion ofthe grips or test fixtures during the test. Rate of motion of thedriven grip or fixture when the machine is running idle may beused
25、if it can be shown that the resulting speed of testing iswithin the limits of variation allowed.9.2 The standard speed of testing shall be 1.36 0.3 mm/min(0.050 6 0.010 in./min).10. Procedure10.1 Measure the width of the specimen between thenotches to the nearest 0.025 mm (0.001 in.).10.2 Mount the
26、specimen in the supporting jig (Fig. 1)sothat it is flush with the base and centered. Tighten the nuts ofthe jig with the torque wrench of 6.1.6 to a torque of0.113 + 0.000, 0.028 Nm (1.00 + 0.00, 0.25 lbfin.). Placethe assembly in the compression tool described in 6.1.3.10.3 Set the speed control a
27、t 1.3 mm/min (0.050 in./min)and start the machine.10.4 Record the maximum load carried by the specimenduring the test. (Usually this will be the load at the moment ofrupture.)10.5 Determine the length of the failed (sheared) area to thenearest 0.025 mm (0.001 in.) by measurement of this surfacewith
28、respect to either half of the ruptured specimen. Thistechnique affords the most accurate determination of the lengthof the sheared plane defined by the separation of the notchesmachined in the specimen.11. Calculation11.1 In-Plane Shear StrengthCalculate the in-plane shearstrength by dividing the ma
29、ximum shear load carried by thespecimen during the test by the product of the width of thespecimen (see 10.1) and the length of the failed area, asdetermined in 10.5. Express the result in megapascals orpounds-force per square inch and report it to three significantfigures.12. Report12.1 Report the
30、following information:FIG. 1 Specimen and Loading Jig for In-Plane Shear TestD3846 08 (2015)212.1.1 Complete identification of the material tested, includ-ing type, source, manufacturers code number, form, principaldimensions, previous history, etc.,12.1.2 Method of preparing test specimens,12.1.3 C
31、onditioning procedure used,12.1.4 Atmospheric conditions in test room,12.1.5 Number of specimens tested,12.1.6 A brief description of the type of testing machineused, and the date on which it was last verified (see 6.1.2) andby whom,12.1.7 In-plane shear strength, average value, and standarddeviatio
32、n, and12.1.8 Date of test.13. Precision and Bias13.1 Table 1 is based on a round robin conducted in 2001 inaccordance with Practice E691, involving two materials testedby five laboratories. For each material, all the samples wereprepared at one source, but the individual specimens wereprepared at th
33、e laboratories which tested them. Each test resultwas the average of five individual determinations. Each labo-ratory obtained four test results for each material. (WarningThe explanation of “r” and “R” in 13.2.1 and 13.2.2 are onlyintended to present a meaningful way of considering theapproximate p
34、recision of this test method. The data in Table 1should not be applied to acceptance or rejection of materials, asthese data apply only to the materials tested in the round robinand are unlikely to be rigorously representative of other lots,formulations, conditions, materials, or laboratories. Users
35、 ofthis test method should apply the principles outlined in PracticeE691 to generate data specific to their materials and laboratory(or between specific laboratories). The principles of 13.2 13.2.2 would then be valid for such data.)13.2 Concept of “r” and “R” in Table 1If Srand SRhavebeen calculate
36、d from a large enough body of data, and for testresults that were averages from testing five specimens for eachtest result, then:13.2.1 Repeatability: Two results obtained within one labo-ratory shall be judged not equivalent if they differ by more thanthe “r” value for that material. “r” is the int
37、erval representingthe critical difference between two test results for the samematerial, obtained by the same operator using the sameequipment on the same day in the same laboratory.13.2.2 Reproducibility: Two test results obtained by differ-ent laboratories shall be judged not equivalent if they di
38、ffer bymore than the “R” value for that material. “R” is the intervalrepresenting the critical difference between two test results forthe same material, obtained by different operators using differ-ent equipment in different laboratories.13.3 Any judgement in accordance with 13.2.1 or 13.2.2would ha
39、ve an approximate 95% (0.95) probability of beingcorrect.13.4 There are no recognized standards by which to esti-mate bias of this method.14. Keywords14.1 compressive shear; in-plane shear; plastics; reinforcedplasticsASTM International takes no position respecting the validity of any patent rights
40、asserted in connection with any item mentionedin 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 tim
41、e by the responsible technical committee and must 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 r
42、eceive 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 I
43、nternational, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or th
44、rough the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 1 Precision Statement for In-Plane ShearMaterial Mean SrASRBrCRDVinyl Ester 3042 775 1241 2171
45、3474Polyester 2898 710 1296 1989 3631ASr= within laboratory standard deviation for the indicated material. It is obtainedby pooling the within-laboratory standard deviations of the test results for all of theparticipating laboratories:Sr5 ffsS1d21sS2d2.1sSnd2g/n g12BSR= between-laboratories reproducibility, expressed as standard deviation:SR5 fSr21SL2g12where SL= standard deviation of laboratory means.Cr = within-laboratory critical interval between tow test results = 2.8 Sr.DR = between-laboratories critical interval between tow test results = 2.8 SR.D3846 08 (2015)3
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