1、Designation: D 5467/D 5467M 97 (Reapproved 2004)Standard Test Method forCompressive Properties of Unidirectional Polymer MatrixComposite Materials Using a Sandwich Beam1This standard is issued under the fixed designation D 5467/D 5467M; the number immediately following the designation indicates they
2、ear of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of lastreapproval. A superscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the in-plane compressive pr
3、op-erties of polymer matrix composite materials reinforced byhigh-modulus fibers in a sandwich beam configuration. Thecomposite material forms are limited to continuous-fiber com-posites of unidirectional orientation. This test procedure intro-duces compressive load into a thin skin bonded to a thic
4、khoneycomb core with the compressive load transmitted into thesample by subjecting the beam to four-point bending.1.2 This procedure is applicable primarily to laminatesmade from prepreg or similar product forms. Other productforms may require deviations from the test method.1.3 The values stated in
5、 either SI units or inch-pound unitsare to be regarded separately as standard. Within the text theinch-pounds units are shown in brackets. The values stated ineach system are not exact equivalents; therefore, each systemmust be used independently of the other. Combining valuesfrom the two systems ma
6、y result in nonconformance with thestandard.NOTE 1Additional procedures for determining compressive proper-ties of polymer matrix composites may be found in Test MethodsD 3410/D 3410M and D 695.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use.
7、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 695 Test Method for Compressive Properties of RigidPlasticsD 792 Test Method
8、s for Density and Specific Gravity (Rela-tive Density) of Plastics by DisplacementD 883 Terminology Relating to PlasticsD 2584 Test Method for Ignition Loss of Cured ReinforcedResinsD 2734 Test Method for Void Content of Reinforced Plas-ticsD 3171 Test Method for Constituent Content of CompositeMate
9、rialsD 3410/D 3410M Test Method for Compressive Propertiesof Polymer Matrix Composite Materials with UnsupportedGage Section by Shear LoadingD 3878 Terminology for Composite MaterialsD 5229/D 5229M Test Method for Moisture AbsorptionProperties and Equilibrium Conditioning of Polymer Ma-trix Composit
10、e MaterialsE 4 Practices for Force Verification of Testing MachinesE 6 Terminology Relating to Methods of Mechanical Test-ingE 111 Test Method for Youngs Modulus, Tangent Modulus,and Chord ModulusE 122 Practice for Calculating Sample Size to Estimate,With a Specified Tolerable Error, the Average for
11、 aCharacteristic of a Lot or ProcessE 177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE 251 Test Methods for Performance Characteristics ofMetallic Bonded Resistance Strain GagesE 456 Terminology Relating to Quality and StatisticsE 1237 Guide for Installing Bonded Resistance
12、StrainGagesE 1309 Guide for Idenitification of Fiber-ReinforcedPolymer-Matrix Composite Materials in DatabasesE 1434 Guide for Recording Mechanical Test Data of Fiber-Reinforced Composite Materials in DatabasesE 1471 Guide for Identification of Fibers, Fillers, and CoreMaterials in Computerized Mate
13、rial Property Databases3. Terminology3.1 DefinitionsTerminology D 3878 defines terms relatingto high-modulus fibers and their composites. TerminologyD 883 defines terms relating to plastics. Terminology E 6defines terms relating to mechanical testing. Terminology1This test method is under the jurisd
14、iction of ASTM Committee D30 onComposite Materials and is the direct responsibility of Subcommittee D30.04 onLamina and Laminate Test Methods.Current edition approved Mar. 1, 2004. Published March 2004. Originallyapproved in 1993. Last previous edition approved in 1997 as D 5467/D 5467M 97e1.2For re
15、ferenced 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.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, W
16、est Conshohocken, PA 19428-2959, United States.E 456 and Practice E 177 define terms relating to statistics. Inthe event of a conflict between terms, Terminology D 3878shall have precedence over the other terminology standards.3.2 Definitions of Terms Specific to This Standard:3.2.1 nominal value, n
17、a value, existing in name only,assigned to a measurable property for the purpose of conve-nient designation. Tolerances may be applied to a nominalvalue to define an acceptable range for the property.3.2.2 orthotropic material, na material with a property ofinterest that, at a given point, possesses
18、 three mutually perpen-dicular planes of symmetry defining the principal materialcoordinate system for that property.3.2.3 principal material coordinate system, na coordinatesystem with axes that are normal to the planes of symmetry thatexist within the material.3.2.4 reference coordinate system, na
19、 coordinate systemfor laminated composites used to define ply orientations. Oneof the reference coordinate system axes (normally the Carte-sian x-axis) is designated the reference axis, assigned aposition, and the ply principal axis of each ply in the laminateis referenced relative to the reference
20、axis to define the plyorientation for that ply.3.2.5 specially orthotropic, adja description of an ortho-tropic material as viewed in its principal material coordinatesystem. In laminated composites, a specially orthotropic lami-nate is a balanced and symmetric laminate of the (0i/90j)nsfamily as vi
21、ewed from the reference coordinate system, suchthat the membrane-bending coupling terms of the stress-strainrelation are zero.3.2.6 transition strain, etransition, nthe strain value at themid-range of the transition region between the two essentiallylinear portions of a bilinear stress-strain or str
22、ain-strain curve(a transverse strain-longitudinal strain curve as used for deter-mining Poissons ratio).3.3 Symbols:3.3.1 adistance between neutral axes of test and oppositefacesheets.3.3.2 Across-sectional area of test facesheet.3.3.3 CVsample coefficient of variation, in percent.3.3.4 Eomodulus of
23、 elasticity of the opposite facesheet inthe test direction.3.3.5 Efmodulus of elasticity of the test facesheet in thetest direction.3.3.6 Fcuultimate compressive strength.3.3.7 Gxzthrough-thickness shear modulus of elasticity.3.3.8 hcthickness of core.3.3.9 sccompressive normal stress.4. Summary of
24、Test Method4.1 A sandwich beam composed of two facesheets separatedby a relatively deep honeycomb core, as shown in Fig. 1, isloaded in four-point bending. The main component of thecompression test specimen is the face sheet that is loaded incompression during flexure, with the material direction of
25、interest oriented along the length of the beam. The otherfacesheet is of a material and size carefully selected to precludeits influence on the test results. The ultimate compressivestrength of the material is determined from the load at whichthe test facesheet of the sandwich beam fails in an accep
26、tablecompression failure mode. If the specimen strain is monitoredwith strain or deflection transducers then the stress-strainresponse of the material can be determined, from which can bederived the compressive modulus of elasticity for this configu-ration.FIG. 1 Longitudinal Compression Sandwich Be
27、am Test SpecimenD 5467/D 5467M 97 (2004)25. Significance and Use5.1 This test method is designed to produce membranecompressive property data for material specifications, researchand development, quality assurance, and structural design andanalysis. Factors that influence the compressive response an
28、dshould therefore be reported include the following: material,methods of material and specimen preparation, specimenconditioning, environment of testing, specimen alignment,speed of testing, time at reinforcement. Properties, in the testdirection, that may be obtained from this test method include:5
29、.1.1 Ultimate compressive strength,5.1.2 Ultimate compressive strain,5.1.3 Compressive (linear or chord) modulus of elasticity,and5.1.4 Transition strain.6. Interferences6.1 Test Method SensitivitiesCompressive strength for asingle material system has been shown to differ when deter-mined by differe
30、nt test methods. Such differences can beattributed to specimen alignment effects, specimen geometryeffects, and fixture effects even though efforts have been madeto minimize these effects.6.2 Material and Specimen PreparationCompressivemodulus, and especially compressive strength, are sensitive topo
31、or material fabrication practices, damage induced by im-proper coupon machining, and lack of control of fiber align-ment. Fiber alignment relative to the specimen coordinate axisshould be maintained as carefully as possible, although nostandard procedure to insure this alignment exists. Proceduresfo
32、und satisfactory include the following: fracturing a curedunidirectional laminate near one edge parallel to the fiberdirection to establish the 0 direction or laying in smallfilament count tows of contrasting color fiber (aramid in carbonlaminates and carbon in aramid or glass laminates) parallel to
33、the 0 direction either as part of the prepreg production or aspart of panel fabrication.6.3 CalculationStress equations are based on beamtheory.7. Apparatus7.1 MicrometersThe micrometer(s) shall use a suitablesize diameter ball-interface on irregular surfaces such as thebag-side of a laminate, and a
34、 flat anvil interface on machinededges or very smooth tooled surfaces. The accuracy of theinstruments shall be suitable for reading to within 1 % of thesample width and thickness. For typical specimen geometries,an instrument with an accuracy of 62.5 m 60.0001 in. isdesirable for thickness measureme
35、nt, while an instrument withan accuracy of 625 m 60.001 in. is desirable for widthmeasurement.7.2 Compressive FixtureA fixture of four loading cylin-ders or cylindrical supports capable of loading the sandwichbeam as shown in Fig. 1. The fixture shall be installed betweenthe steel platens of the tes
36、ting machine. To avoid local crushingor failure as a result of stress concentrations under the loadingcylinders, the diameter of loading cylinders may be up to 1.5times the sandwich thickness, and loading pads may be neededunder the loading cylinders (see 11.6).7.3 Testing MachineThe testing machine
37、 shall be inconformance with Practices E 4 and shall satisfy the followingrequirements:7.3.1 Testing Machine HeadsThe testing machine shallhave two loading heads, with at least one movable along thetesting axis.7.3.2 Drive MechanismThe testing machine drive mecha-nism shall be capable of imparting t
38、o the movable head acontrolled displacement rate with respect to the stationaryhead. The displacement rate of the movable head shall becapable of being regulated as specified in 11.3.7.3.3 Load IndicatorThe testing machine load-sensingdevice shall be capable of indicating the total load beingcarried
39、 by the test specimen. This device shall be essentiallyfree from inertia lag at the specified rate of testing and shallindicate the load with an accuracy over the load range(s) ofinterest of within 61 % of the indicated value, as specified byPractices E 4. The load range(s) of interest may be fairly
40、 lowfor modulus evaluation, much higher for strength evaluation, orboth, as required.NOTE 2Obtaining precision load data over a large range of interest inthe same test, such as when both elastic modulus and ultimate load arebeing determined, place extreme requirements on the load cell and itscalibra
41、tion. For some equipment, a special calibration may be required.For some combinations of material and load cell, simultaneous precisionmeasurement of both elastic modulus and ultimate strength may not bepossible, and measurement of modulus and strength may have to beperformed in separate tests using
42、 a different load cell range for each test.7.4 Strain-Indicating DeviceStrain data, if required, shallbe determined by means of strain gages.7.4.1 Bonded Resistance Strain GagesStrain gage selec-tion is a compromise based on the procedure and the type ofmaterial to be tested. Strain gages should hav
43、e an active gridlength of 3 mm 0.125 in. or less; (1.5 mm 0.06 in. ispreferable). Gage calibration certification shall comply withTest Methods E 251. Some guidelines on the use of straingages on composites are presented below, with a generaldiscussion on the subject in Footnote 8.37.4.1.1 Surface pr
44、eparation of fiber-reinforced compositesin accordance with Practice E 1237 can penetrate the matrixmaterial and cause damage to the reinforcing fibers, resultingin improper coupon failures. Reinforcing fibers shall not beexposed or damaged during the surface preparation process.Consult the strain ga
45、ge manufacturer regarding surface prepa-ration guidelines and recommended bonding agents for com-posites.7.4.1.2 Select gages having larger resistances to reduceheating effects on low-conductivity materials. Resistances of350 V or higher are preferred. Use the minimum possible gageexcitation voltage
46、 consistent with the desired accuracy (1 to 2V is recommended) to reduce further the power consumed bythe gage. Heating of the coupon by the gage may affect theperformance of the material directly, or it may affect theindicated strain as a result of a difference between the gage3Pendleton, R. P. and
47、 Tuttle, M. E., Manual on Experimental Methods forMechanical Testing of Composites, Society for Experimental Mechanics, Bethel,CT, 1989.D 5467/D 5467M 97 (2004)3temperature compensation factor and the coefficient of thermalexpansion of the coupon material.7.4.1.3 Temperature compensation is recommen
48、ded whentesting at Standard Laboratory Atmosphere. Temperature com-pensation is required when testing in nonambient temperatureenvironments. When appropriate, use a traveler coupon(dummy calibration coupon) with identical lay-up and straingage orientations for thermal strain compensation.7.4.1.4 Con
49、sider the transverse sensitivity of the selectedstrain gage. Consult the strain gage manufacturer for recom-mendations on transverse sensitivity corrections.7.5 Conditioning ChamberWhen conditioning materialsin other than ambient laboratory environments, a temperature/vapor-level controlled environmental conditioning chamber isrequired that shall be capable of maintaining the requiredrelative temperature to within 63C 65F and the requiredrelative vapor level to within 65 %. Chamber conditions shallbe monitored either on an automated
