1、Designation: C1358 11C1358 13Standard Test Method forMonotonic Compressive Strength Testing of ContinuousFiber-Reinforced Advanced Ceramics with Solid RectangularCross-Section Test Specimens at Ambient Temperatures1This standard is issued under the fixed designation C1358; the number immediately fol
2、lowing the designation indicates the year oforiginal adoption or, in the case of revision, 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. Scope Scope*1.1 This tes
3、t method covers the determination of compressive strength including stress-strain behavior under monotonicuniaxial loading of continuous fiber-reinforced advanced ceramics at ambient temperatures. This test method addresses, but is notrestricted to, various suggested test specimen geometries as list
4、ed in the appendix. In addition, test specimen fabrication methods,testing modes (force, displacement, or strain control), testing rates (force rate, stress rate, displacement rate, or strain rate),allowable bending, and data collection and reporting procedures are addressed. Compressive strength as
5、 used in this test methodrefers to the compressive strength obtained under monotonic uniaxial loading where monotonic refers to a continuous nonstop testrate with no reversals from test initiation to final fracture.1.2 This test method applies primarily to advanced ceramic matrix composites with con
6、tinuous fiber reinforcement:uni-directional (1D), bi-directional (2D), and tri-directional (3D) or other multi-directional reinforcements. In addition, this testmethod may also be used with glass (amorphous) matrix composites with 1D, 2D, 3D, and other multi-directional continuousfiber reinforcement
7、s. This test method does not directly address discontinuous fiber-reinforced, whisker-reinforced, or particulate-reinforced ceramics, although the test methods detailed here may be equally applicable to these composites.1.3 The values stated in SI units are to be regarded as the standard and are in
8、accordance with SI 10-02 IEEE/ASTM SI 10 .1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory
9、limitations prior to use. Refer to Section 7 for specific precautions.2. Referenced Documents2.1 ASTM Standards:2C1145 Terminology of Advanced CeramicsD695 Test Method for Compressive Properties of Rigid PlasticsD3379 Test Method for Tensile Strength and Youngs Modulus for High-Modulus Single-Filame
10、nt MaterialsD3410/D3410M Test Method for Compressive Properties of Polymer Matrix Composite Materials with Unsupported GageSection by Shear LoadingD3479/D3479M Test Method for Tension-Tension Fatigue of Polymer Matrix Composite MaterialsD3878 Terminology for Composite MaterialsD6856 Guide for Testin
11、g Fabric-Reinforced “Textile” Composite MaterialsE4 Practices for Force Verification of Testing MachinesE6 Terminology Relating to Methods of Mechanical TestingE83 Practice for Verification and Classification of Extensometer SystemsE337 Test Method for Measuring Humidity with a Psychrometer (the Mea
12、surement of Wet- and Dry-Bulb Temperatures)E1012 Practice for Verification of Testing Frame and Specimen Alignment Under Tensile and Compressive Axial ForceApplication1 This test method is under the jurisdiction of ASTM Committee C28 on Advanced Ceramics and is the direct responsibility of Subcommit
13、tee C28.07 on Ceramic MatrixComposites.Current edition approved July 15, 2011Feb. 15, 2013. Published August 2011March 2013. Originally approved in 1996. Last previous edition approved in 20052011 asC1358 05.C1358 11. DOI: 10.1520/C1358-1110.1520/C1358-132 For referencedASTM standards, visit theASTM
14、 website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indi
15、cation of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all 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 c
16、onsidered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1SI 10-02 IEEE/ASTM SI 10 American National Standard for Use of the International System o
17、f Units (SI): The Modern MetricSystem3. Terminology3.1 Definitions:3.1.1 The definitions of terms relating to compressive testing, advanced ceramics, and fiber-reinforced composites, appearingin Terminology E6, Test Method D695, Practice E1012, Terminology C1145, Test Method D3410/D3410M, and Termin
18、ologyD3878 apply to the terms used in this test method. Pertinent definitions are shown as follows with the appropriate source givenin parentheses. Additional terms used in conjunction with this test method are defined in 3.2.3.2 Definitions of Terms Specific to This Standard:3.2.1 advanced ceramic,
19、 nhighly engineered, high-performance predominantly non-metallic, inorganic, ceramic materialhaving specific functional attributes. C11453.2.2 axial strain LL1, naverage longitudinal strains measured at the surface on opposite sides of the longitudinal axis ofsymmetry of the specimen by two strain-s
20、ensing devices located at the mid length of the reduced section. E10123.2.3 bending strain LL1, ndifference between the strain at the surface and the axial strain. In general, the bending strainvaries from point to point around and along the reduced section of the specimen. E10123.2.4 breaking force
21、 F, nforce at which fracture occurs. E63.2.5 ceramic matrix composite, nmaterial consisting of two or more materials (insoluble in one another), in which the major,continuous component (matrix component) is a ceramic, while the secondary component(s) (reinforcing component) may beceramic, glass-cera
22、mic, glass, metal, or organic in nature. These components are combined on a macroscale to form a usefulengineering material possessing certain properties or behavior not possessed by the individual constituents.3.2.6 compressive strength FL2, nmaximum compressive stress which a material is capable o
23、f sustaining. Compressivestrength is calculated from the maximum force during a compression test carried to rupture and the original cross-sectional areaof the specimen. E63.2.7 continuous fiber-reinforced ceramic matrix composite (CFCC), nceramic matrix composite in which the reinforcingphase consi
24、sts of a continuous fiber, continuous yarn, or a woven fabric.3.2.8 gage length L, noriginal length of that portion of the specimen over which strain or change of length is determined.E63.2.9 modulus of elasticity FL2, nratio of stress to corresponding strain below the proportional limit. E63.2.10 p
25、roportional limit stress in compression FL2 , ngreatest stress that a material is capable of sustaining without anydeviation from proportionality of stress to strain (Hookes law).3.2.10.1 DiscussionMany experiments have shown that values observed for the proportional limit vary greatly with the sens
26、itivity and accuracy of thetesting equipment, eccentricity of loading, the scale to which the stress-strain diagram is plotted, and other factors. Whendetermination of proportional limit is required, specify the procedure and sensitivity of the test equipment. E63.2.11 percent bending, nbending stra
27、in times 100 divided by the axial strain. E10123.2.12 slow crack growth (SCG), nsubcritical crack growth (extension) which may result from, but is not restricted to, suchmechanisms as environmentally-assisted stress corrosion or diffusive crack growth. C11454. Significance and Use4.1 This test metho
28、d may be used for material development, material comparison, quality assurance, characterization, reliabilityassessment, and design data generation.4.2 Continuous fiber-reinforced ceramic matrix composites (CFCCs) are generally characterized by fine-grain sized (65 %relative humidity (RH) is not rec
29、ommended.5.2 Surface preparation of test specimens, although normally not considered a major concern in CFCCs, can introducefabrication flaws that may have pronounced effects on compressive mechanical properties and behavior (for example, shape andlevel of the resulting stress-strain curve, compress
30、ive strength and strain, proportional limit stress and strain, etc.) Machiningdamage introduced during test specimen preparation can be either a random interfering factor in the determination of ultimatestrength of pristine material (that is, increased frequency of surface-initiated fractures compar
31、ed to volume-initiated fractures), oran inherent part of the strength characteristics to be measured. Surface preparation can also lead to the introduction of residualstresses. Universal or standardized test methods of surface preparation do not exist. In addition, the nature of fabrication used for
32、certain composites (for example, chemical vapor infiltration or hot pressing) may require the testing of test specimens in theas-processed condition (that is, it may not be possible to machine the test specimen faces without compromising the in-plane fiberarchitecture). Final machining steps may, or
33、 may not, negate machining damage introduced during the initial machining. Thus,report test specimen fabrication history since it may play an important role in the measured strength distributions.5.3 Bending in uniaxial compressive tests can introduce eccentricity leading to geometric instability of
34、 the test specimen andbuckling failure before true compressive strength is attained. In addition, if deformations or strains are measured at surfaces wheremaximum or minimum stresses occur, bending may introduce over or under measurement of strains depending on the location ofthe strain-measuring de
35、vice on the test specimen. Bending can be introduced from, among other sources, initial load trainmisalignment, misaligned test specimens as installed in the grips, warped test specimens, or load train misalignment introducedduring testing due to low lateral machine/grip stiffness.5.4 Fractures that
36、 initiate outside the uniformly stressed gage section of a test specimen may be due to factors such as stressconcentrations or geometrical transitions, extraneous stresses introduced by gripping, or strength-limiting features in themicrostructure of the test specimen. Such non-gage section fractures
37、 will normally constitute invalid tests. In addition, for frictionalface-loaded geometrics, gripping pressure is a key variable in the initiation of fracture. Insufficient pressure can shear the outerplies in laminated CFCCs; while too much pressure can cause local crushing of the CFCC and may initi
38、ate fracture in the vicinityof the grips.5.5 Lateral supports are sometimes used in compression tests to reduce the tendency of test specimen buckling. However, suchlateral supports may introduce sufficient frictional stress so as to artificially increase the force required to produce compressivefai
39、lure. In addition, the lateral supports and attendant frictional stresses may invalidate the assumption of uniaxial stress state.When lateral supports are used, the frictional effect should be quantified to ensure that its contribution is small, and the means fordoing so reported along with the quan
40、tity of the frictional effect.6. Apparatus6.1 Testing Machines Machines used for compressive testing shall conform to Practices E4. The forces used in determiningcompressive strength shall be accurate within 61 % at any force within the selected force range of the testing machine as definedin Practi
41、ces E4. A schematic showing pertinent features of one possible compressive testing apparatus is shown in Fig. 1.6.2 Gripping Devices:C1358 1336.2.1 GeneralVarious types of gripping devices may be used to transmit the measured force applied by the testing machineto the test specimens. The brittle nat
42、ure of the matrices of CFCCs requires a uniform interface between the grip components andthe gripped section of the test specimen. Line or point contacts and nonuniform pressure can produce Hertzian-type stresses leadingto crack initiation and fracture of the test specimen in the gripped section.6.2
43、.1.1 The primary recommended gripping system for compressive testing CFCCs employs active grip interfaces that requirea continuous application of a mechanical, hydraulic, or pneumatic force to transmit the force applied by the test machine to thetest specimen. These types of grip interfaces (that is
44、, frictional face-loaded grips) cause a force to be applied normal to the surfaceof the gripped section of the test specimen. Transmission of the uniaxial force applied by the test machine is then accomplishedby friction between the test specimen and the grip faces. Thus, important aspects of active
45、 grip interfaces are uniform contactbetween the gripped section of the test specimen and the grip faces and constant coefficient of friction over the grip/specimeninterface.6.2.1.2 For flat test specimens, frictional face-loaded grips, either by direct lateral pressure grip faces (1)3 or by indirect
46、wedge-type grip faces, act as the grip interface (2,3) as illustrated in Fig. 2 and Fig. 3, respectively. Generally, close tolerancesare required for the flatness and parallelism as well as for the wedge angle of the wedge grip faces. In addition, the thickness,flatness, and parallelism of the gripp
47、ed section of the test specimen must be within similarly close tolerances to promote uniformcontact at the test specimen/grip interface. Tolerances will vary depending on the exact configuration as shown in the appropriatetest specimen drawings.3 The boldface numbers given in parentheses refer to a
48、list of references at the end of the text.FIG. 1 Schematic Diagram of One Possible Apparatus for Conducting a Uniaxially-Loaded Compression TestFIG. 2 Example of a Direct Lateral Pressure Grip Face for a Face-Loaded Grip InterfaceC1358 1346.2.1.3 Sufficient lateral pressure must be applied to preven
49、t slippage between the grip face and the test specimen. Grip surfacesthat are scored or serrated with a pattern similar to that of a single-cut file have been found satisfactory. A fine serration appearsto be the most satisfactory. Keep the serrations clean and well-defined but not overly sharp. The length and width of the grip facesshall be equal to or greater than the respective length and width of the gripped sections of the test specimen.6.2.1.4 An alternative recommended gripping system for compressive testing CFCCs employs passiv
