1、Designation: C1275 16C1275 18Standard Test Method forMonotonic Tensile Behavior of Continuous Fiber-ReinforcedAdvanced Ceramics with Solid Rectangular Cross-SectionTest Specimens at Ambient Temperature1This standard is issued under the fixed designation C1275; the number immediately following the de
2、signation 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. Scope1.1 This test method covers the
3、determination of tensile behavior including tensile strength and stress-strain response undermonotonic uniaxial loading of continuous fiber-reinforced advanced ceramics at ambient temperature. This test method addresses,but is not restricted to, various suggested test specimen geometries as listed i
4、n the appendix. In addition, test specimen fabricationmethods, testing modes (force, displacement, or strain control), testing rates (force rate, stress rate, displacement rate, or strainrate), allowable bending, and data collection and reporting procedures are addressed. Note that tensile strength
5、as used in this testmethod refers to the tensile strength obtained under monotonic uniaxial loading where monotonic refers to a continuous nonstoptest rate with no reversals from test initiation to final fracture.1.2 This test method applies primarily to all advanced ceramic matrix composites with c
6、ontinuous fiber reinforcement:uni-directional (1-D), bi-directional (2-D), and tri-directional (3-D).unidirectional (1D), bidirectional (2D), and tridirectional (3D).In addition, this test method may also be used with glass (amorphous) matrix composites with 1-D, 2-D,1D, 2D, and 3-D3Dcontinuous fibe
7、r reinforcement. This test method does not address directly address discontinuous fiber-reinforced, whisker-reinforcedwhisker-reinforced, or particulate-reinforced ceramics, although the test methods detailed here may be equallyapplicable to these composites.1.3 Values expressed in this test method
8、are in accordance with the International System of Units (SI) and 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 safety, health, and health
9、environmental practices and determine theapplicability of regulatory limitations prior to use. Specific hazard statements are given in Section 7 and 8.2.5.2.1.5 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Dec
10、ision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2C1145 Terminology of Advanced CeramicsC1239 Practice for Reporting Uniaxial Stre
11、ngth Data and Estimating Weibull Distribution Parameters for Advanced CeramicsD3039/D3039M Test Method for Tensile Properties of Polymer Matrix Composite MaterialsD3379 Test Method for Tensile Strength and Youngs Modulus for High-Modulus Single-Filament MaterialsD3878 Terminology for Composite Mater
12、ialsE4 Practices for Force Verification of Testing MachinesE6 Terminology Relating to Methods of Mechanical TestingE83 Practice for Verification and Classification of Extensometer SystemsE177 Practice for Use of the Terms Precision and Bias in ASTM Test MethodsE337 Test Method for Measuring Humidity
13、 with a Psychrometer (the Measurement of Wet- and Dry-Bulb Temperatures)1 This test method is under the jurisdiction of ASTM Committee C28 on Advanced Ceramics and is the direct responsibility of Subcommittee C28.07 on Ceramic MatrixComposites.Current edition approved Dec. 1, 2016Jan. 1, 2018. Publi
14、shed January 2017January 2018. Originally approved in 1994. Last previous edition approved in 20152016 asC1275 15.C1275 16. DOI: 10.1520/C1275-16.10.1520/C1275-18.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book
15、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 indication of what changes have been made to the previous version. Becauseit may not be technica
16、lly 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 considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box
17、C700, West Conshohocken, PA 19428-2959. United States1E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test MethodE1012 Practice for Verification of Testing Frame and Specimen Alignment Under Tensile and Compressive Axial ForceApplicationIEEE/ASTM SI 10 American
18、National Standard for Use of the International System of Units (SI): The Modern Metric System3. Terminology3.1 Definitions:3.1.1 The definitions of terms relating to tensile testing appearing in Terminology E6 apply to the terms used in this test method.The definitions of terms relating to advanced
19、ceramics appearing inTerminology C1145 apply to the terms used in this test method.The definitions of terms relating to fiber-reinforced composites appearing in Terminology D3878 apply to the terms used in thistest method. Pertinent definitions as listed in Practice E1012, Terminology and Terminolog
20、ies C1145, Terminology D3878, andTerminology E6 are shown in the following with the appropriate source given in parentheses.Additional terms used in conjunctionwith this test method are defined in the following:3.1.2 advanced ceramic, nhighly engineered, high performance high-performance, predominan
21、tly nonmetallic, inorganic,ceramic material having specific functional attributes. C11453.1.3 axial strainaverage longitudinal strains measured at the surface on opposite sides of the longitudinal axis of symmetryof the specimen by two strain-sensing devices located at the mid length of the reduced
22、section. E10123.1.4 bending straindifference between the strain at the surface and the axial strain. In general, the bending strain varies frompoint to point around and along the reduced section of the specimen. E10123.1.5 breaking forceforce at which fracture occurs. E63.1.6 ceramic matrix composit
23、ecomposite, nmaterial consisting of two or more materials (insoluble in one another), inwhich the major, continuous component (matrix component) is a ceramic, while the secondary component/s (reinforcingcomponent) may be ceramic, glass-ceramic, glass, metal, or organic in nature. These components ar
24、e combined on a macroscaleto form a useful engineering material possessing certain properties or behavior not possessed by the individual constituents.3.1.7 continuous fiber-reinforced ceramic matrix composite (CFCC)(CFCC), nceramic matrix composite in which thereinforcing phase consists of a contin
25、uous fiber, continuous yarn, or a woven fabric.3.1.8 gage lengthoriginal length of that portion of the specimen over which strain or change of length is determined. E63.1.9 matrix-cracking stressapplied tensile stress at which the matrix cracks into a series of roughly parallel blocks normalto the t
26、ensile stress.3.1.9 Discussionmatrix-cracking stress, FL2, nIn some cases, the matrix cracking stress may be indicated on thestress-strain curve by deviation from linearity (proportional limit) or incremental drops in the stress with increasing strain. In othercases, especially with materials which
27、do not possess a linear portion of the stress-strain curve, the matrix cracking stress may beindicated as the first stress at which a permanent offset strain is detected in the unloading stress-strain (elastic limit).applied tensilestress at which the matrix cracks into a series of roughly parallel
28、blocks normal to the tensile stress.3.1.9.1 DiscussionIn some cases, the matrix-cracking stress may be indicated on the stress-strain curve by deviation from linearity (proportional limit)or incremental drops in the stress with increasing strain. In other cases, especially with materials which do no
29、t possess a linearportion of the stress-strain curve, the matrix-cracking stress may be indicated as the first stress at which a permanent offset strainis detected in the unloading stress-strain (elastic limit).3.1.10 modulus of elasticityratio of stress to corresponding strain below the proportiona
30、l limit. E63.1.11 modulus of resilienceresilience, FLL3, nstrain energy per unit volume required to elastically stress the materialfrom zero to the proportional limit, indicating the ability of the material to absorb energy when deformed elastically and returnit when unloaded.3.1.13 modulus of tough
31、nessstrain energy per unit volume required to stress the material from zero to final fracture indicatingthe ability of the material to absorb energy beyond the elastic range (that is, damage tolerance of the material).3.1.12 Discussionmodulus of toughness, FLL3, n The modulus of toughness can also b
32、e referred to as the cumulativedamage energy and as such is regarded as an indication of strain energy per unit volume required to stress the material from zeroto final fracture, indicating the ability of the material to sustain damage rather than as a material property. Fracture mechanicsmethods fo
33、r the characterization of CFCCs have not been developed. The determination of the modulus of toughness as providedin this test method for the characterization of the cumulative damage process in CFCCs may become obsolete when fracturemechanics methods for CFCCs become available.absorb energy beyond
34、the elastic range (that is, damage tolerance of the material).3.1.12.1 DiscussionC1275 182The modulus of toughness can also be referred to as the cumulative damage energy and as such is regarded as an indication ofthe ability of the material to sustain damage rather than as a material property. Frac
35、ture mechanics methods for the characterizationof CFCCs have not been developed. The determination of the modulus of toughness as provided in this test method for thecharacterization of the cumulative damage process in CFCCs may become obsolete when fracture mechanics methods for CFCCsbecome availab
36、le.3.1.13 proportional limit stresspercent bendinggreatest stress that a material is capable of sustaining without any deviationfrom proportionality of stress to strain (Hookes law).bending strain times 100 divided by the axial strain. E10123.1.14 Discussionproportional limit stressMany experiments
37、have shown that values observed for the proportional limitvary greatly with the sensitivity and accuracy of the testing equipment, eccentricity of loading, the scale to which the stress-straindiagram is plotted, and other factors. When determination of proportional limit is required, the procedure a
38、nd sensitivity of the testequipment should be specified. (See Terminology greatest stress that a material is capable of sustaining without any deviation fromproportionality of stress to strain (Hookes law).E6.)3.1.14.1 DiscussionMany experiments have shown that values observed for the proportional l
39、imit vary greatly with the sensitivity 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, the procedure and sensitivity of the test equipment should be specifi
40、ed. (SeeTerminology E6.)3.1.17 percent bendingbending strain times 100 divided by the axial strain. E10123.1.15 slow crack growthsubcritical crack growth (extension) which may result from, but is not restricted to, such mechanismsas environmentally-assisted environmentally assisted stress corrosion
41、or diffusive crack growth.3.1.16 tensile strengthmaximum tensile stress which a material is capable of sustaining. Tensile strength is calculated fromthe maximum load during a tension test carried to rupture and the original cross-sectional area of the specimen. E64. Significance and Use4.1 This tes
42、t method may be used for material development, material comparison, quality assurance, characterization, anddesign data generation.4.2 Continuous fiber-reinforced ceramic matrix composites generally characterized by fine grain sized grain-sized (65 %relative humidity (RH) is not recommended and any
43、deviations from this recommendation must be reported.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 tensile mechanical properties and behavior (for example, shape and levelof the
44、 resulting stress-strain curve, tensile strength and strain, proportional limit stress and strain, etc.). Machining damageintroduced during specimen preparation can be either a random interfering factor in the determination of ultimate strength ofpristine material (that is, increased frequency of su
45、rface initiated surface-initiated fractures compared to volume initiatedvolume-initiated fractures), or an inherent part of the strength characteristics to be measured. Surface preparation can also lead tothe introduction of residual stresses. Universal or standardized test methods of surface prepar
46、ation do not exist. It should beunderstood that final machining steps may,may or may not negate machining damage introduced during the initial machining.Thus, test specimen fabrication history may play an important role in the measured strength distributions and should be reported.In addition, the n
47、ature of fabrication used for certain composites (for example, chemical vapor infiltration or hot pressing) mayrequire the testing of test specimens in the as-processed condition (that is, it may not be possible to machine the specimen faces).5.3 Bending in uniaxial tensile tests can cause or promot
48、e non-uniformnonuniform stress distributions with maximum stressesoccurring at the test specimen surface, leading to nonrepresentative fractures originating at surfaces or near geometrical transitions.In addition, if deformations or strains are measured at surfaces where maximum or minimum stresses
49、occur, bending may introduceover or under measurement of strains depending on the location of the strain-measuring strain measuring device on the testspecimen. Similarly, fracture from surface flaws may be accentuated or suppressed by the presence of the non-uniformnonuniformstresses caused by bending.5.4 Fractures that initiate outside the uniformly-stressed uniformly stressed gage section of a test specimen may be due to factorssuch as stress concentrations or geometrical transitions, extraneous stresses introduced by gripping, or streng
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