1、Designation:D5448/D5448M93 (Reapproved 2006) Designation: D5448/D5448M 11Standard Test Method forInplane Shear Properties of Hoop Wound Polymer MatrixComposite Cylinders1This standard is issued under the fixed designation D5448/D5448M; the number immediately following the designation indicates theye
2、ar 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 () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Depart
3、ment of Defense.1. Scope1.1 This test method determines the inplane shear properties of wound polymer matrix composites reinforced by high-moduluscontinuous fibers. It describes testing of hoop wound (90) cylinders in torsion for determination of inplane shear properties.1.2The values stated in eith
4、er SI units or inch-pound units are to be regarded separately as standard. Within the text theinch-pound units are shown in brackets. The values stated in each system are not exact equivalents; therefore, each system mustbe used independently of the other. Combining values from the two systems may r
5、esult in nonconformance with the test method.1.31.2 The technical content of this standard has been stable since 1993 without significant objection from its stakeholders.As thereis limited technical support for the maintenance of this standard, changes since that date have been limited to items requ
6、ired toretain consistency with otherASTM D30 Committee standards, including editorial changes and incorporation of updated guidanceon specimen preconditioning and environmental testing. The standard therefore should not be considered to include any significantchanges in approach and practice since 1
7、993. Future maintenance of the standard will only be in response to specific requests andperformed only as technical support allows.1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in eachsystem are not exact equivalents; there
8、fore, each system must be used independently of the other. Combining values from the twosystems may result in nonconformance with the test method.1.3.1 Within the text the inch-pound units are shown in brackets.1.4 This standard does not purport to address all of the safety concerns, if any, associa
9、ted with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D792 Test Methods for Density and Specific Gravity (Relative De
10、nsity) of Plastics by DisplacementD883 Terminology Relating to PlasticsD2584 Test Method for Ignition Loss of Cured Reinforced ResinsD2734 Test Methods for Void Content of Reinforced PlasticsD3171 Test Methods for Constituent Content of Composite MaterialsD3878 Terminology for Composite MaterialsD52
11、29/D5229M Test Method for Moisture Absorption Properties and Equilibrium Conditioning of Polymer Matrix CompositeMaterialsD5449/D5449M Test Method for Transverse Compressive Properties of Hoop Wound Polymer Matrix Composite CylindersD5450/D5450M Test Method for Transverse Tensile Properties of Hoop
12、Wound Polymer Matrix Composite CylindersE6 Terminology Relating to Methods of Mechanical TestingE111 Test Method for Youngs Modulus, Tangent Modulus, and Chord ModulusE122 Practice for Calculating Sample Size to Estimate, With Specified Precision, the Average for a Characteristic of a Lot orProcess1
13、This test method is under the jurisdiction of ASTM Committee D30 on Composite Materials and is the direct responsibility of Subcommittee D30.04 on Lamina andLaminate Test Methods.Current edition approved Jan.Nov. 15, 2006.2011. Published January 2006.December 2011. Originally approved in 1993. Last
14、previous edition approved in 20002006 asD5448/D5448M 93 (2000).(2006). DOI: 10.1520/D5448_D5448M-93R06.10.1520/D5448_D5448M-11.2For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information,
15、refer to the standards Document Summary page on the ASTM website.1This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict al
16、l changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-29
17、59, United States.E177 Practice for Use of the Terms Precision and Bias in ASTM Test MethodsE251 Test Methods for Performance Characteristics of Metallic Bonded Resistance Strain GaugesE456 Terminology Relating to Quality and StatisticsE691 Practice for Conducting an Interlaboratory Study to Determi
18、ne the Precision of a Test MethodE1237 Guide for Installing Bonded Resistance Strain Gages3. Terminology3.1 DefinitionsTerminology D3878 defines terms relating to high-modulus fibers and their composites. Terminology D883defines terms relating to plastics. Terminology E6 defines terms relating to me
19、chanical testing. Terminology E456 and PracticeE177 define terms relating to statistics. In the event of a conflict between terms, Terminology D3878 shall have precedence overother standards.NOTE 1If the term represents a physical quantity, its analytical dimensions are stated immediately following
20、the term (or letter symbol) infundamental dimension form, using the following ASTM standard symbology for fundamental dimensions, shown within square brackets: M for mass,L for length, T for time, u for thermodynamic temperature, and nd for non-dimensional quantities. Use of these symbols is restric
21、ted to analyticaldimensions when used with square brackets, as the symbols may have other definitions when used without the brackets.3.2 Description of Terms Specific to This Standard:33.2.1 hoop wound, na winding of a cylindrical component where the filaments are circumferentially oriented.3.2.2 in
22、plane shear modulus, G12 MTML1T2, nthe elastic shear modulus of a unidirectional material in the plane definedby axes parallel and perpendicular to the reinforcing fibers.3.2.3 inplane shear strain at failure, g12und, nthe value of inplane shear strain at failure when an inplane shear loadforceis ap
23、plied to the material.3.2.4 inplane shear strength, t12,MT2L1ML1T2, nthe strength of a unidirectional material when an inplane shearloadforce is applied to the material.3.2.5 specimena single part cut from a winding that meets the specifications of Fig. 1. Each winding may yield severalspecimens.3.2
24、.6 windingan entire part completed by one winding operation and then cured.4. Summary of Test Method4.1 A thin walled hoop wound cylinder nominally 100 mm 4 in. in diameter and 140 mm 512 in. in length is bonded intotwo end fixtures. The specimen/fixture assembly is mounted in the testing machine an
25、d monotonically loaded in inplane shearwhile recording load.force. The inplane shear strength can be determined from the maximum loadforce carried prior to failure. Ifthe cylinder strain is monitored with strain gages then the stress-strain response, the inplane shear strain at failure, and the inpl
26、aneshear modulus can be derived.5. Significance and Use5.1 This test method is designed to produce inplane shear property data for material specifications, research and development,3If the term represents a physical quantity, its analytical dimensions are stated immediately following the term (or le
27、tter symbol) in fundamental dimension form, usingthe following ASTM standard symbology for fundamental dimensions, shown within square brackets: M for mass, L for length, T for time, u for thermodynamictemperature, and nd for nondimensional quantities. Use of these symbols is restricted to analytica
28、l dimensions when used with square brackets, as the symbols may haveother definitions when used without the brackets.FIG. 1 Assembly Drawing for the Shear Fixture and SpecimenD5448/D5448M 112quality assurance, and structural design and analysis. Factors that influence the inplane shear response and
29、should therefore bereported are material, method of material preparation, specimen preparation, specimen conditioning, environment of testing,specimen alignment and gripping, speed of testing, void content, and fiber volume fraction. Properties, in the test direction, thatmay be obtained from this t
30、est method are as follows:5.1.1 Inplane Shear Strength, t12u,5.1.2 Inplane Shear Strain at Failure, g12u, and5.1.3 Inplane Shear Modulus, G12.6. Interferences6.1 Material and Specimen PreparationPoor material fabrication practices, lack of control of fiber alignment, and damageinduced by improper co
31、uponspecimen machining are known causes of high material data scatter in composites.6.2 Bonding Specimens to Test FixturesA high percentage of failures in or near the bond between the test specimen and thetest fixture, especially when combined with high material data scatter, is an indicator of spec
32、imen bonding problems.Specimen-to-fixture bonding is discussed in 11.5.6.3 System AlignmentExcessive bending or axial loading will cause premature failure, as well as highly inaccurate shearmodulus determination. Every effort should be made to eliminate excess bending and axial loading from the test
33、 system. Bendingand axial loading may occur due to misaligned grips, misaligned specimens in the test fixtures, or from departures of the specimensfrom tolerance requirements. The alignment should always be checked as discussed in 12.213.2.7. Apparatus7.1 Micrometers, suitable ball type for reading
34、to within 0.025 6 0.010 mm 0.001 6 0.0004 in. of the specimen inner andouter diameters. Flat anvil type or micrometer calipers of similar resolution may be used for the overall specimen length and thegage length (the free length between the fixtures).7.2 Inplane Shear FixtureThe inplane shear fixtur
35、e consists of a steel outer shell, insert, and adaptor. An assembly drawingfor these components and the test fixture is shown in Fig. 1.7.2.1 Outer ShellThe outer shell (SI units, see Fig. 2; inch-pound units, see Fig. 3) is circular with a concentric circular hollowin one face, a groove along the d
36、iameter of the other face, and a center hole through the thickness.Along the diameter perpendicularto the groove, three pairs of small eccentric holes are placed at three radial distances. The two outer pairs of holes are threaded.Four additional threaded holes are placed at the same radial distance
37、 as the innermost pair of holes at 90 intervals starting 45from the diameter that passes through the center groove.7.2.2 InsertThe fixture insert is circular with a center hole through the thickness (SI units, see Fig. 4; inch-pound units, seeFig. 5). Two sets of holes are placed along a concentric
38、centerline. These holes align with the innermost set of holes in the outershell. The set of 4 holes at 90 intervals are counterbored. The insert is fastened inside the hollow of the outer shell to form theconcentric groove used to put the specimen in the fixture.7.2.3 AdaptorThe adaptor is circular
39、with a square central torque nut raising out of one face, a flange along a diameter onthe other face, and a central hole (SI units, see Fig. 6; inch-pound units, see Fig. 7). Two bolt holes are placed equidistant fromthe adaptor center on a diameter perpendicular to the centerline of the flange. The
40、 adaptor is fastened to the outer shell. The flangeof the adaptor fits into the groove of the outer shell. The complete inplane shear specimen/fixture assembly is seen in Fig. 1.NOTE1The 2The outer shell and insert for the compression fixture are the same outer shell and insert used for the fixtures
41、 in Test MethodsD5449/D5449M and D5450/D5450M.7.3 Testing Machine, comprised of the following:7.3.1 Fixed MemberA fixed or essentially stationary member, with respect to rotation, to which one end of the torsionspecimen/fixture/adaptor assembly, shown in Fig. 3, can be attached.7.3.2 Rotational Memb
42、erA rotational member to which the opposite end of the torsion specimen/fixture/adaptor assembly,shown in Fig. 1, can be attached. Either the rotational member or the fixed member shall be free to move axially to prevent theapplication of axial forces or the axial loadforce shall be limited to 5 % o
43、f the axial strength of the material.7.3.3 Drive Mechanism, for imparting to the movable member a uniform controlled angular velocity with respect to the fixedmember. This angular velocity is to be regulated as specified in Section 9.7.3.4 LoadForce IndicatorA suitable load-indicatingforce-indicatin
44、g mechanism capable of showing the total torsionalloadforce carried by the test specimen. This mechanism shall be essentially free of inertia-lag at the specified rate of testing andshall indicate the loadforce within an accuracy of 61 % of the actual value, or better.7.3.5 Construction MaterialsThe
45、 fixed member, movable member, drive mechanism, fixtures, and adaptors shall beconstructed of such materials and in such proportions that the total rotational deformation of the system contributed by these partsis minimized.7.4 Strain-Indicating DeviceLoadForce versus strain data shall be determined
46、 by means of bonded resistance strain gages.Each strain gage shall be 6.3 mm 0.25 in. in length. Strain gage rosettes (0/45/90) shall be used to correct for gagemisalignment. Gage calibration certification shall comply with Test Method E251. Some guidelines on the use of strain gages onD5448/D5448M
47、113composites are presented in 7.4.1-7.4.4. A general reference on the subject is Tuttle and Brinson.47.4.1 Surface PreparationThe surface preparation of fiber-reinforced composites discussed in Guide E1237 can penetrate thematrix material and cause damage to the reinforcing fibers, resulting in imp
48、roper couponspecimen failures. Reinforcing fibersshould not be exposed or damaged during the surface preparation process. The strain gage manufacturer should be consultedregarding surface preparation guidelines and recommended bonding agents for composites, pending the development of a set ofstandar
49、d practices for strain gage installation surface preparation of fiber-reinforced composite materials.7.4.2 Gage ResistanceConsideration should be given to the selection of gages having larger resistance to reduce heatingeffects on low-conductivity materials. Resistances of 350V or higher are preferred. Additional considerations should be given tothe use of the minimum possible gage excitation voltage consistent with the desired accuracy (1 to 2 V is recommended) to furtherreduce the power consumed by the g
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