1、Designation: D3914 02 (Reapproved 2016)Standard Test Method forIn-Plane Shear Strength of Pultruded Glass-ReinforcedPlastic Rod1This standard is issued under the fixed designation D3914; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revisi
2、on, 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 in-plane shear strength of pultruded, glass-fiber rei
3、nforced, ther-mosetting plastic rod of diameters ranging from 19 to 32 mm(34 to 114 in.).1.2 The values stated in SI units are to be regarded as thestandard.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 o
4、f this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. Specific precau-tionary statements are given in Note 2 and Note 3.NOTE 1There is no known ISO equivalent to this standard.2. Referenced Documents2.1 ASTM Sta
5、ndards:2D618 Practice for Conditioning Plastics for TestingD695 Test Method for Compressive Properties of RigidPlasticsE4 Practices for Force Verification of Testing Machines3. Terminology3.1 Definitions:3.1.1 in-plane shear strengththe shear strength at maxi-mum load in which the plane of fracture
6、is centrally locatedalong the longitudinal axis of the specimen between twodiametrically opposed notches machined halfway through itsdiameter.4. Summary of Test Method4.1 In-plane shear strength, as determined by this testmethod, is measured by applying a compressive load tonotched cylindrical speci
7、mens of the type shown in Fig. 1.Loading of the specimen is accomplished with a subpress, orcompression tool, such as those shown in Fig. 1 and Fig. 2 ofTest Method D695. Failure of the specimen occurs in shearbetween two centrally located notches, diametrically opposedand machined halfway through i
8、ts diameter at a fixed distanceapart. The notches are accurately machined in the specimenwith maximum reproducibility by means of a special notchingjig (Fig. 2a and Fig. 2b) designed specifically for this purpose.5. Significance and Use5.1 Shear tests of various kinds are widely used in thereinforce
9、d plastics industry to assess the strength 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 valu
10、e to the fibrous reinforcement industry, since they canbe used to determine the potential of new sizing systems for thesurface treatment of glass fibers.5.2 The in-plane shear strength of pultruded cylindricalcomposites is an important property from an engineeringstandpoint, since pultruded rod, as
11、such, is used in manystructural applications.6. Apparatus6.1 Testing MachineAny suitable testing machine capableof control of constant-rate-of-crosshead movement and com-prising essentially the following:6.1.1 Drive MechanismA drive mechanism for impartingto the movable member a uniform, controlled
12、velocity withrespect to the stationary member, as required in 10.3.6.1.2 Load IndicatorA load-indicating mechanism ca-pable of showing the total compressive load carried by the testspecimen. The mechanism shall be essentially free of inertiallag at the specified rate of testing and shall indicate th
13、e loadwith an accuracy of 61 % of the maximum 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 Notching JigAnotching jig of the type shown in Fig.2a and Fig. 2b, or the equivalent, for notching the test
14、specimens.1This 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 April 1, 2016. Published April 2016. Originallyapproved in 1980. Last previous edition approved
15、 in 2008 as D3914 - 02(2008).DOI: 10.1520/D3914-02R16.2For 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.Copyrig
16、ht ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States16.1.4 Compression ToolA compression tool for applyingthe load to the test specimen, such as those shown in Fig. 1 andFig. 2 of Test Method D695.6.1.5 MicrometersSuitable micrometers, reading to
17、 0.025mm or 0.001 in., for measuring the diameter of the specimen,as well as the depth of, and distance between, the notches.7. Test Specimens7.1 ConfigurationTest specimens shall be carefully ma-chined from the rod sample of interest and shall conform to theshape and dimensions given in Fig. 1. The
18、 ends of thespecimen shall be machined flat and parallel to prevent pointloading upon application of the compressive load.7.2 PreparationAfter machining the specimen to properlength, insert it in the notching jig, flush it with one face of thejig, and tighten the cap screws of the jig to secure it i
19、n place.Push the assembly (jig and specimen) into a diamond gritcutoff wheel (or equivalent blade) after setting the blade to givethe proper depth of notch. This arrangement is shown in Fig. 3.Guidance of the jig during specimen notching is by means ofsliding contact with the fence of the table saw
20、as the jig ispushed along the table to a stop. After machining one notch,turn the tool over and repeat the procedure to provide a secondnotch in the specimen diametrically opposed to the first and ata fixed, defined distance (Fig. 1) from it.NOTE 2Caution: When fabricating composite specimens by mac
21、hin-ing operations, a fine dust consisting of particles of fibers or the matrixmaterial, or both, may be formed.These fine dusts can be a health or safetyhazard, or both.Adequate protection should be afforded operating person-nel and equipment. This may require adequate ventilation or dustcollecting
22、 facilities, or both, at a minimum.7.3 NumberA minimum of five specimens 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 ofPractice D618, for those te
23、sts where conditioning is required.In cases 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%FIG. 1 Notched Rod In-Plane Shear Specimen; Dimensions: Top, mm; Bott
24、om, in.D3914 02 (2016)2relative humidity, unless otherwise specified. 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 th
25、edriven grip or fixture when the machine is running idle may beused 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 1.3 6 0.3 mm(0.050 6 0.010 in.)/min.10. Procedure10.1 Measure the diameter of the specimen be
26、tween thenotches to the nearest 0.025 mm or 0.001 in.10.2 Center the specimen in the compression tool of 6.1.4and mount the tool between the loading heads of the testingmachine.10.3 Set the speed control at 1.3 mm/min (0.050 in./min)and start the machine.10.4 Record the maximum load carried by the s
27、pecimenduring the test (usually, this will be the load at the moment ofrupture).NOTE 3Caution: When testing composite materials, it is possible tostore considerable energy in the test specimen which can be released withconsiderable force on rupture. This can release small high velocityparticles and
28、dust consisting of fractured fibers and matrix materials. Theparticles and fine dust can potentially be a health or safety hazard, or both.Adequate protection should be afforded operating personnel, bystanders,and the equipment. This may require shielding or dust collection facilities,or both, at a
29、minimum.10.5 Determine the length of the failed (sheared) area to thenearest 0.025 mm or 0.001 in. by measurement of this surfacewith 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
30、the notchesmachined in the specimen.NOTE 4The width of the notches and the distance between them mayvary somewhat from the dimensions indicated in Fig. 1, depending uponthe actual thickness of the circular saw blade used to machine the notchesand the particular notching jig used. However, round-robi
31、n tests of rods ofvarious diameters, employing different notching tools and saw blades ofthickness up to 3.2 mm (18 in.), have shown little, if any, influence on theNOTE 1Dimensioned in mmFIG. 2 A Details of Specimen Notching Jig for In-Plane Shear TestD3914 02 (2016)3test results due to variation o
32、f the notches attributed to these factors. Aparticularly attractive feature of the notching jig shown in Fig. 2a and Fig.2b is its ability to accommodate rods ranging in diameter from 19 to 32mm (34 to 114 in.).11. Calculations11.1 In-Plane Shear StrengthCalculate the in-plane shearstrength by divid
33、ing the maximum shear load carried by thespecimen during the test by the product of the specimensdiameter (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 The r
34、eport shall include the following:12.1.1 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 Conditioning procedure used,12.1.4 Atmospheric conditions in
35、 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 standarddeviation, and12.1.8 Date of test.13. Precision and Bias313.1 Repea
36、tabilityTesting in a single laboratory of asample of pultruded laminate resulted in a within-laboratorycoefficient of variation of 5.9%. The within-laboratory criticalinterval (cr) between two test results is 16.58% (2.8 Vr). Tworesults obtained within one laboratory on the same materialshall be jud
37、ged not equivalent if they differ by more than thecritical interval (cr). Attempts to develop a full precision andbias statement for this test method have not been successful.For this reason, data on precision and bias cannot be given.Because this test method does not contain a round robin basednume
38、rical precision and bias statement, it shall not be used as3Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:D20-1083.NOTE 1Dimensioned in InchesFIG. 2 B Details of Specimen Notching Jig for In-Plane Shear Test (continued)D3914 02
39、 (2016)4a referee method in case of dispute. Anyone wishing toparticipate in the development of precision and bias datashould contact the Chairman, Subcommittee D20.18 (Section20.18.02), ASTM, 100 Barr Harbor Drive, WestConshohocken, PA 19428.NOTE 5An attempt to run a round robin in 2001 resulted in
40、insufficient laboratories to develop a bias between laboratory precisionstatements. Only three laboratories were available for participation whena minimum of six is required.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mention
41、edin 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
42、 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 receive careful consideration at a meeting of
43、 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
44、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 through the ASTM website(www.astm.org). Permis
45、sion rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 3 Arrangement for Machining Notches in Pultruded Rod Specimens. Notching Jig Accommodates Rods Ranging in Diameter from19 mm (34 in.) to 32 mm (114 in.)D3914 02 (2016)5
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