1、Designation: C1360 17Standard Practice forConstant-Amplitude, Axial, Tension-Tension Cyclic Fatigueof Continuous Fiber-Reinforced Advanced Ceramics atAmbient Temperatures1This standard is issued under the fixed designation C1360; the number immediately following the designation indicates the year of
2、original 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 practice covers the determination of constant-amplitud
3、e, axial tension-tension cyclic fatigue behavior andperformance of continuous fiber-reinforced advanced ceramiccomposites (CFCCs) at ambient temperatures. This practicebuilds on experience and existing standards in tensile testingCFCCs at ambient temperatures and addresses various sug-gested test sp
4、ecimen geometries, specimen fabricationmethods, testing modes (force, displacement, or strain control),testing rates and frequencies, allowable bending, and proce-dures for data collection and reporting. This practice does notapply to axial cyclic fatigue tests of components or parts (thatis, machin
5、e elements with nonuniform or multiaxial stressstates).1.2 This practice applies primarily to advanced ceramicmatrix composites with continuous fiber reinforcement: uni-directional (1-D), bi-directional (2-D), and tri-directional (3-D)or other multi-directional reinforcements. In addition, thispract
6、ice may also be used with glass (amorphous) matrixcomposites with 1-D, 2-D, 3-D, and other multi-directionalcontinuous fiber reinforcements. This practice does not directlyaddress discontinuous fiber-reinforced, whisker-reinforced orparticulate-reinforced ceramics, although the methods detailedhere
7、may be equally applicable to these composites.1.3 The values stated in SI units are to be regarded as thestandard and are in accordance with IEEE/ASTM SI 10.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user o
8、f this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. Refer to Section 7for specific precautions.2. Referenced Documents2.1 ASTM Standards:2C1145 Terminology of Advanced CeramicsC1275 Test Method for Monotonic T
9、ensile Behavior ofContinuous Fiber-Reinforced Advanced Ceramics withSolid Rectangular Cross-Section Test Specimens at Am-bient TemperatureD3479/D3479M Test Method for Tension-Tension Fatigueof Polymer Matrix Composite MaterialsD3878 Terminology for Composite MaterialsE4 Practices for Force Verificat
10、ion of Testing MachinesE6 Terminology Relating to Methods of Mechanical TestingE83 Practice for Verification and Classification of Exten-someter SystemsE337 Test Method for Measuring Humidity with a Psy-chrometer (the Measurement of Wet- and Dry-Bulb Tem-peratures)E467 Practice for Verification of C
11、onstant Amplitude Dy-namic Forces in an Axial Fatigue Testing SystemE468 Practice for Presentation of Constant Amplitude Fa-tigue Test Results for Metallic MaterialsE739 Practice for StatisticalAnalysis of Linear or LinearizedStress-Life (S-N) and Strain-Life (-N) Fatigue DataE1012 Practice for Veri
12、fication of Testing Frame and Speci-men Alignment Under Tensile and Compressive AxialForce ApplicationE1150 Definitions of Terms Relating to Fatigue (Withdrawn1996)3E1823 Terminology Relating to Fatigue and Fracture TestingIEEE/ASTM SI 10 Standard for Use of the InternationalSystem of Units (SI) (Th
13、e Modern Metric System)3. Terminology3.1 Definitions:1This practice is under the jurisdiction of ASTM Committee C28 on AdvancedCeramics and is the direct responsibility of Subcommittee C28.07 on CeramicMatrix Composites.Current edition approved Feb. 1, 2017. Published February 2017. Originallyapprov
14、ed in 1996. Last previous edition approved in 2015 as C1360 10 (2015).DOI: 10.1520/C1360-17.2For referenced 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 S
15、ummary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internation
16、ally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.13.1.1 Definitions of terms relating to advanced cerami
17、cs,fiber-reinforced composites, tensile testing, and cyclic fatigueas they appear in Terminology C1145, Terminology D3878,Terminology E6, and Terminology E1823, respectively, applyto the terms used in this practice. Selected terms with defini-tions not specific to this practice follow in 3.2 with th
18、eappropriate source given in parenthesis. Terms specific to thispractice are defined in 3.3.3.2 Definitions of Terms Specific to This Standard:3.2.1 advanced ceramic, nA highly engineered, high per-formance predominately non-metallic, inorganic, ceramic ma-terial having specific functional attribute
19、s. (See TerminologyC1145.)3.2.2 axial strain LL1, nthe average longitudinal strainsmeasured at the surface on opposite sides of the longitudinalaxis of symmetry of the test specimen by two strain-sensingdevices located at the mid length of the reduced section. (SeePractice E1012.)3.2.3 bending strai
20、n LL1, nthe difference between thestrain at the surface and the axial strain. In general, the bendingstrain varies from point to point around and along the reducedsection of the test specimen. (See Practice E1012.)3.2.4 ceramic matrix composite, na material consisting oftwo or more materials (insolu
21、ble in one another), in which themajor, continuous component (matrix component) is a ceramic,while the secondary component(s) (reinforcing component)may be ceramic, glass-ceramic, glass, metal, or organic innature. These components are combined on a macroscale toform a useful engineering material po
22、ssessing certain proper-ties or behavior not possessed by the individual constituents.(See Terminology C1145.)3.2.5 continuous fiber-reinforced ceramic matrix composite(CFCC), na ceramic matrix composite in which the reinforc-ing phase consists of a continuous fiber, continuous yarn, or awoven fabri
23、c. (See Terminology C1145.)3.2.6 constant amplitude loading, nin cyclic fatigueloading, a loading in which all peak loads are equal and all ofthe valley loads are equal. (See Terminology E1823.)3.2.7 cyclic fatigue, nthe process of progressive localizedpermanent structural change occurring in a mate
24、rial subjectedto conditions that produce fluctuating stresses and strains atsome point or points and that may culminate in cracks orcomplete fracture after a sufficient number of fluctuations. (SeeTerminology E1823.) See Fig. 1 for nomenclature relevant tocyclic fatigue testing.3.2.7.1 DiscussionIn
25、glass technology, static tests of con-siderable duration are called “static fatigue” tests, a type of testgenerally designated as stress-rupture.3.2.7.2 DiscussionFluctuations may occur both in forceand with time (frequency) as in the case of “random vibration.”3.2.8 cyclic fatigue life, Nfthe numbe
26、r of loading cycles ofa specified character that a given test specimen sustains beforefailure of a specified nature occurs. (See Terminology E1823.)3.2.9 cyclic fatigue limit, SfFL2, nthe limiting value ofthe median cyclic fatigue strength as the cyclic fatigue life, Nf,becomes very large, (for exam
27、ple, Nf106107). (See Termi-nology E1823.)3.2.9.1 DiscussionCertain materials and environmentspreclude the attainment of a cyclic fatigue limit. Valuestabulated as “fatigue limits” in the literature are frequently (butnot always) values of Sfat 50 % survival at Nfcycles of stressin which the mean str
28、ess, Sm, equals zero.3.2.10 cyclic fatigue strength SN, FL2, nthe limitingvalue of the median cyclic fatigue strength at a particular cyclicfatigue life, Nf(See Terminology E1823).3.2.11 gage length, L, nthe original length of thatportion of the test specimen over which strain or change oflength is
29、determined. (See Terminology E6.)3.2.12 force ratio, nin cyclic fatigue loading, the algebraicratio of the two loading parameters of a cycle; the most widelyused ratios (See Terminology E1150, E1823):R 5minimum forcemaximum forceor R 5valley forcepeak forceandA 5force amplitudemean forceor A 5maximu
30、m force 2 minimum force!maximum force1minimum force!3.2.13 matrix-cracking stress FL2, nThe applied ten-sile stress at which the matrix cracks into a series of roughlyparallel blocks normal to the tensile stress. (See Test MethodC1275.)3.2.13.1 DiscussionIn some cases, the matrix-crackingstress may
31、be indicated on the stress-strain curve by deviationfrom linearity (proportional limit) or incremental drops in thestress with increasing strain. In other cases, especially withmaterials that do not possess a linear portion of the stress-straincurve, the matrix cracking stress may be indicated as th
32、e firststress at which a permanent offset strain is detected in theunloading stress-strain curve (elastic limit).3.2.14 modulus of elasticity FL2, nThe ratio of stress tocorresponding strain below the proportional limit. (See Termi-nology E6.)3.2.15 proportional limit stress FL2, nthe greateststress
33、 that a material is capable of sustaining without anydeviation from proportionality of stress to strain (Hookes law).(See Terminology E6.)FIG. 1 Cyclic Fatigue Nomenclature and Wave FormsC1360 1723.2.15.1 DiscussionMany experiments have shown thatvalues observed for the proportional limit vary great
34、ly with thesensitivity and accuracy of the testing equipment, eccentricityof loading, the scale to which the stress-strain diagram isplotted, and other factors. When determination of proportionallimit is required, specify the procedure and sensitivity of thetest equipment.3.2.16 percent bending, nth
35、e bending strain times 100divided by the axial strain. (See Practice E1012.)3.2.17 S-N diagram, na plot of stress versus the number ofcycles to failure. The stress can be maximum stress, Smax,minimum stress, Smin, stress range, S or Sr, or stressamplitude, Sa. The diagram indicates the S-N relations
36、hip for aspecified value of Sm, , R and a specified probability ofsurvival. For N, a log scale is almost always used, although alinear scale may also be used. For S, a linear scale is usuallyused, although a log scale may also be used. (See TerminologyE1150 and Practice E468.)3.2.18 slow crack growt
37、h, nsubcritical crack growth (ex-tension) that may result from, but is not restricted to, suchmechanisms as environmentally assisted stress corrosion ordiffusive crack growth. (See Terminology C1145.)3.2.19 tensile strength FL2, nthe maximum tensilestress which a material is capable of sustaining. T
38、ensilestrength is calculated from the maximum force during a tensiontest carried to rupture and the original cross-sectional area ofthe test specimen. (See Terminology E6.)3.3 Definitions of Terms Specific to This Standard:3.3.1 fracture strength FL2, nthe tensile stress that thematerial sustains at
39、 the instant of fracture. Fracture strength iscalculated from the force at fracture during a tension testcarried to rupture and the original cross-sectional area of thetest specimen.3.3.1.1 DiscussionIn some cases, the fracture strengthmay be identical to the tensile strength if the force at fractur
40、eis the maximum for the test.3.3.2 maximum stress, SmaxFL2, nthe maximum ap-plied stress during cyclic fatigue.3.3.3 mean stress, SmFL2, nthe difference between themean stress and the maximum or minimum stress such thatSm5Smax1Smin2(1)3.3.4 minimum stress, SminFL2, nthe minimum appliedstress during
41、cyclic fatigue.3.3.5 stress amplitude, SaFL2, nthe difference betweenthe mean stress and the maximum stress such thatSa5Smax2 Smin25 Smax2 Sm5 Sm2 Smin(2)3.3.6 stress range, SorSrFL2, nthe difference be-tween the maximum stress and the minimum stress such thatS 5 Sr5 Smax2 Smin(3)3.3.7 time to cycli
42、c fatigue failure, tft, ntotal elapsedtime from test initiation to test termination required to reach thenumber of cycles to failure.4. Significance and Use4.1 This practice may be used for material development,material comparison, quality assurance, characterization, reli-ability assessment, and de
43、sign data generation.4.2 Continuous fiber-reinforced ceramic matrix compositesare generally characterized by crystalline matrices and ceramicfiber reinforcements. These materials are candidate materialsfor structural applications requiring high degrees of wear andcorrosion resistance, and high-tempe
44、rature inherent damagetolerance (that is, toughness). In addition, continuous fiber-reinforced glass matrix composites are candidate materials forsimilar but possibly less demanding applications. Althoughflexural test methods are commonly used to evaluate themechanical behavior of monolithic advance
45、d ceramics, thenonuniform stress distribution in a flexural test specimen inaddition to dissimilar mechanical behavior in tension andcompression for CFCCs leads to ambiguity of interpretation oftest results obtained in flexure for CFCCs. Uniaxially loadedtensile tests provide information on mechanic
46、al behavior for auniformly stressed material.4.3 The cyclic fatigue behavior of CFCCs can have appre-ciable nonlinear effects (for example, sliding of fibers withinthe matrix) which may be related to the heat transfer of thespecimen to the surroundings. Changes in test temperature,frequency, and hea
47、t removal can affect test results. It may bedesirable to measure the effects of these variables to moreclosely simulate end-use conditions for some specific applica-tion.4.4 Cyclic fatigue by its nature is a probabilistic phenom-enon as discussed in STP 91A (1) and STP 588 (2).4Inaddition, the stren
48、gths of the brittle matrices and fibers ofCFCCs are probabilistic in nature. Therefore, a sufficientnumber of test specimens at each testing condition is requiredfor statistical analysis and design, with guidelines for sufficientnumbers provided in STP 91A (1), STP 588 (2), and PracticeE739. Studies
49、 to determine the influence of test specimenvolume or surface area on cyclic fatigue strength distributionsfor CFCCs have not been completed. The many differenttensile test specimen geometries available for cyclic fatiguetesting may result in variations in the measured cyclic fatiguebehavior of a particular material due to differences in thevolume of material in the gage section of the test specimens.4.5 Tensile cyclic fatigue tests provide information on thematerial response under fluctuating uni
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