1、Designation: D 3552 96 (Reapproved 2007)Standard Test Method forTensile Properties of Fiber Reinforced Metal MatrixComposites1This standard is issued under the fixed designation D 3552; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revisio
2、n, 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.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 This test method cove
3、rs the determination of the tensileproperties of metal matrix composites reinforced by continuousand discontinuous high-modulus fibers. Nontraditional metalmatrix composites as stated in 1.1.6 also are covered in this testmethod. This test method applies to specimens loaded in auniaxial manner teste
4、d in laboratory air at either room tem-perature or elevated temperatures. The types of metal matrixcomposites covered are:1.1.1 UnidirectionalAny fiber-reinforced composite withall fibers aligned in a single direction. Continuous or discon-tinuous reinforcing fibers, longitudinal and transverse prop
5、er-ties.1.1.2 0/90 Balanced CrossplyA laminate composed ofonly 0 and 90 plies. This is not necessarily symmetric,continuous, or discontinuous reinforcing fibers.1.1.3 Angleply LaminateAny balanced laminate consist-ing of 6 theta plies where theta is an acute angle with respectto a reference directio
6、n. Continuous reinforcing fibers without0 reinforcing fibers (that is, (645)ns, (630)ns, and so forth).1.1.4 Quasi-Isotropic LaminateA balanced and symmet-ric laminate for which a constitutive property of interest, at agiven point, displays isotropic behavior in the plane of thelaminate. Continuous
7、reinforcing fibers with 0 reinforcingfibers (that is, (0/645/90)s, (0/630)s, and so forth).1.1.5 Unoriented and Random Discontinuous Fibers.1.1.6 Directionally Solidified Eutectic Composites.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are prov
8、ided forinformation purposes only.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 and determine the applica-bility of regulatory limita
9、tions prior to use.2. Referenced Documents2.1 ASTM Standards:2D 3878 Terminology for Composite MaterialsE4 Practices for Force Verification of Testing MachinesE8 Test Methods for Tension Testing of Metallic MaterialsE83 Practice for Verification and Classification of Exten-someter SystemsE 177 Pract
10、ice for Use of the Terms Precision and Bias inASTM Test MethodsE 456 Terminology Relating to Quality and StatisticsE 1012 Practice for Verification of Test Frame and Speci-men Alignment Under Tensile and Compressive AxialForce Application3. Terminology3.1 DefinitionsTerminology D 3878 defines terms
11、relatingto high-modulus fibers and their composites. Terminology E 6defines terms relating to mechanical testing. TerminologyE 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 standards.3.2 Def
12、initions of Terms Specific to This Standard:3.2.1 continuous fiber, na polycrystalline or amorphousfiber that is continuous within the sample or component or thathas ends outside of the stress fields under consideration.3.2.2 discontinuous fiber, na polycrystalline or amor-phous fiber that is discon
13、tinuous within the sample or compo-nent or that has its ends inside the stress fields under consid-eration.4. Summary of Test Method4.1 A tension specimen is mounted in the grips of amechanical testing machine and monotonically loaded, intension, at a constant loading rate until specimen failure occ
14、urs.The ultimate strength of the material can be determined fromthe maximum load carried before failure. If the coupon strain1This test method is under the jurisdiction of ASTM Committee D30 onComposite Materials and is the direct responsibility of Subcommittee D30.04 onLamina and Laminate Test Meth
15、ods.Current edition approved May 1, 2007. Published June 2007. Originallyapproved in 1977. Last previous edition approved in 2002 as D 3552 96 (2002).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStand
16、ards volume information, 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.is monitored with strain or displacement transducers, then thestress-strain response of the mate
17、rial can be determined, fromwhich the ultimate tensile strain, proportional limit, and tensilemodulus of elasticity can be derived.5. Significance and Use5.1 This test method is designed to produce tensile propertydata for material specifications, research and development,quality assurance, and stru
18、ctural design and analysis. Factorsthat influence the tensile response and should be reportedinclude the following: material, methods of material prepara-tion and lay-up, specimen stacking sequence, specimen prepa-ration, specimen conditioning, environment of testing, speci-men alignment and grippin
19、g, speed of testing, time attemperature, and volume percent reinforcement. Properties, inthe test direction, which may be obtained from this test methodinclude the following:5.1.1 Ultimate tensile strength,5.1.2 Ultimate tensile strain,5.1.3 Tensile modulus of elasticity, and5.1.4 Poissons ratio.6.
20、Interferences6.1 Tension test data are used as the principal criteria for theengineering design in actual structural applications. Therefore,it is important to define test conditions that will producerealistic tensile properties, including statistical variation. Suchdata will allow the design engine
21、er to determine the mostappropriate and meaningful margin of safety. The followingtest method issues will cause significant data scatter:6.1.1 Material and Specimen PreparationPoor materialfabrication practices, lack of control of fiber alignment, anddamage induced by improper coupon machining are k
22、nowncauses of high material data scatter in composites.6.1.2 GrippingAhigh percentage of grip-induced failures,especially when combined with high material data scatter, is anindicator of specimen gripping problems.6.1.3 System AlignmentExcessive bending will cause pre-mature failure, as well as high
23、ly inaccurate modulus ofelasticity determination. Every effort should be made to elimi-nate excess bending from the test system. Bending may occuras a result of misaligned grips or from specimens themselves ifimproperly installed in the grips or out of tolerance as a resultof poor specimen preparati
24、on. If there is any doubt as to thealignment inherent in a given test machine, then the alignmentshould be checked.7. Apparatus7.1 Micrometers, 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.)
25、isadequate for thickness measurement, while an instrument withan accuracy of 625 m (60.001 in.) is adequate for widthmeasurement.7.2 Testing Machine, comprised of the following:7.2.1 Fixed MemberA fixed or essentially stationarymember carrying one grip.7.2.2 Movable MemberA movable member carrying a
26、second grip.7.2.3 Loading MechanismA loading mechanism for im-parting to the movable member a controlled velocity withrespect to the stationary member, this velocity to be regulatedas specified in Section 10.7.2.4 Load IndicatorA suitable load-indicating mecha-nism capable of showing the total load
27、carried by the testspecimen. This mechanism shall be essentially free of inertialag at the specified rate of testing and shall indicate the loadwith an accuracy of 61 % of the indicated value, or better. Theaccuracy of the testing machine shall be verified in accordancewith Practice E4. Further, the
28、 calibrated load range used for aparticular test shall be chosen to ensure the anticipated maxi-mum loads are between 20 to 80 % of the calibrated load range.This is to ensure a linear calibrated load response and protectthe load indicator from overload conditions.7.2.5 Grips:7.2.5.1 GeneralGrip des
29、igns shall be suited to the speci-mens being tested. The grip designs described in Test MethodsE8shall be applicable but should be sized according to thespecimen dimensions.7.2.5.2 Grips for Round SpecimenThe grips for roundspecimens shall be standard threaded grips or split-shouldergrips with shoul
30、der surfaces designed to mate with correspond-ing specimens described in Section 8. The grips shall beself-aligning.7.2.5.3 Grips for Flat SpecimensThe grips shall bewedge-type grips or lateral pressure grips with serrated orknurled surfaces for contact with the specimen. The grips shallbe self-alig
31、ning; that is, they shall be attached to their respec-tive fixed and movable members in such a manner that whenany load is applied, the grips will place the axis of a correctlymounted specimen in coincidence with the applied load direc-tion such that no significant moment is placed on the specimente
32、st section, either in the thickness or width direction. Thelateral pressure that is imposed by the wedge-type grips orapplied by the lateral pressure grips shall be sufficient toprevent slippage between the grip face and the specimen tabsurface without causing excessive lateral compressive damageto
33、the specimen. If the serrations are too coarse, emery cloth orsimilar materials may be used to distribute the gripping forcemore uniformly over a larger area of the specimen tab. Theserrations shall be maintained clean and care shall be taken tomaintain specimen alignment during installation.7.2.5.4
34、 Grip AlignmentTo ensure a uniform axial tensilestress state within the specimen test section, the following gripalignment criteria shall be maintained. Test systems shall bealigned according to Test Methods E 1012. The alignmentspecimen shall be aligned such that the maximum percentbending througho
35、ut the test section, determined at an appliedaverage strain of 500 e, shall not exceed 10 %, and themaximum measured strain from any of the strain gages on thealignment specimen, as a result of gripping stresses at zeroapplied load, shall not exceed 50 e.7.2.6 StrainStrain should be determined by me
36、ans ofeither strain gages or an extensometer.7.2.6.1 Strain GagesThe strain gage should be not lessthan 3 mm in length for the longitudinal direction and not lessthan 1.5 mm in length for the transverse direction. The gages,D 3552 96 (2007)2surface preparation, and bonding agents should be chosen to
37、provide for adequate performance on the subject materials andsuitable strain-recording equipment shall be used.7.2.6.2 ExtensometersExtensometers used for compositespecimen shall satisfy Practice E83, Class B-1 requirementscan be used in place of strain gages for 25-mm (1-in.) gagelength specimens o
38、r exclusively for high-temperature testsbeyond the range of strain gage applications. Extensometersshall be calibrated periodically in accordance with MethodE83.8. Test Specimens8.1 General:8.1.1 Test Specimen SizeWithin the limitations of materialavailability and economy, the specimens shall be siz
39、ed largeenough to be statistically representative of the material toprovide meaningful data and, where possible, large enough toaffix strain gages or extensometers. Gage lengths incorporatingdeformation-measuring devices shall be at least 13 mm (12 in.)in length.NOTE 1Nonstandard subscaled specimen
40、geometries are supplied forapplications in which material size limitations preclude a 13-mm (12-in.)gage length. These geometries are useful in material development studiesbut are not considered as a standard. Test data from these nonstandardspecimens shall be evaluated and reported separately in li
41、ght of their sizelimitation.8.1.2 Specimen PreparationMechanical property deter-minations of metal matrix composite specimens are particu-larly sensitive to the effects of improper specimen preparationmethods. Great care should be exercised, especially in machin-ing or trimming. Diamond grinding, wa
42、ter jet cutting, orelectrical discharge machining (EDM) shall be used. Obtainfinal dimensions by water-lubricated precision diamond grind-ing. The depth of diamond grinding required should bedetermined through careful examination of the as-machinedsurfaces. Edges should be flat and parallel within t
43、he specifiedtolerances. Grinding must be conducted with adequate precau-tions to minimize damaging vibrations. In the EDM method,the sample must be suitably mounted for good electricalcontact to prevent extraneous arcing and specimen damage.Surface finishing may be accomplished chemically by slightm
44、atrix etching or manually by light sanding or filing.8.1.3 Specimen Cross SectionThe cross section of thespecimen shall be uniform over the gage length. A slight,gradual taper can be tolerated, provided that the minimumsection is at the mid length of the gage length and symmetricalwith respect to it
45、s centerline. In round specimens, the tapershall be limited to a 0.5 % difference in the diameter betweenthe mid length and the ends of the gage length. In flatspecimens, the taper shall not exceed 1 % in the width of thetest section. The thickness shall not be tapered. To be statisti-cally represen
46、tative of the material, a minimum of 200 con-tinuous filaments, chopped fibers, or both, is suggested incomposites that are oriented in the direction of the load.8.2 Flat SpecimensThe standard dimensions of flat speci-mens are shown in Fig. 1 and are discussed in subsequentsections in terms of the v
47、olume fraction and placementgeometry of the reinforcement.8.2.1 Unidirectional and Crossply Laminate Composites:8.2.1.1 Longitudinal SpecimensThe test specimens forunidirectional and crossply laminate composites tested in theaxial direction are shown in Fig. 1, Design A, B, C, D, or E. Ifnecessary t
48、o transition the load into the specimen, or to preventgripping damage to the filaments near the surface, tabs can bebonded onto the specimen gripping section. The tab lengthshall be long enough to provide a shear area, 2WTLTat eachend of the specimen, which is large enough to transfer themaximum loa
49、d to the specimen. For all but the shortestspecimen length, the radius of the curvature of the shouldershould be at least 25 mm (1 in.), and if practical, the edge of theshoulder should be a straight line joining the arc segment andthe corner of the tab section. The recommended standarddesigns for axial specimens of unidirectional and crossplylaminate composites are Designs A and B. Designs C, D, andE are considered standard designs when composite materialsize limitations are encountered. As stated in Note 1, forsize-limited panels or blanks used
