ASTM C1361-01(2007)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation:C1361–01 (Reapproved 2007)
Standard Practice for
Constant-Amplitude, Axial, Tension-Tension Cyclic Fatigue
of Advanced Ceramics at Ambient Temperatures
This standard is issued under the fixed designation C1361; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use. Refer to Section 7
1.1 This practice covers the determination of constant-
for specific precautions.
amplitude, axial tension-tension cyclic fatigue behaviour and
performance of advanced ceramics at ambient temperatures to
2. Referenced Documents
establish “baseline” cyclic fatigue performance. This practice
2.1 ASTM Standards:
builds on experience and existing standards in tensile testing
C1145 Terminology of Advanced Ceramics
advanced ceramics at ambient temperatures and addresses
C1273 Test Method for Tensile Strength of Monolithic
various suggested test specimen geometries, test specimen
Advanced Ceramics at Ambient Temperatures
fabrication methods, testing modes (force, displacement, or
C1322 Practice for Fractography and Characterization of
strain control), testing rates and frequencies, allowable bend-
Fracture Origins in Advanced Ceramics
ing, and procedures for data collection and reporting. This
E4 Practices for Force Verification of Testing Machines
practice does not apply to axial cyclic fatigue tests of compo-
E6 TerminologyRelatingtoMethodsofMechanicalTesting
nents or parts (that is, machine elements with non uniform or
E83 Practice for Verification and Classification of Exten-
multiaxial stress states).
someter Systems
1.2 This practice applies primarily to advanced ceramics
E337 Test Method for Measuring Humidity with a Psy-
that macroscopically exhibit isotropic, homogeneous, continu-
chrometer (the Measurement of Wet- and Dry-Bulb Tem-
ous behaviour. While this practice applies primarily to mono-
peratures)
lithic advanced ceramics, certain whisker- or particle-
E467 Practice for Verification of Constant Amplitude Dy-
reinforced composite ceramics as well as certain discontinuous
namic Forces in an Axial Fatigue Testing System
fibre-reinforced composite ceramics may also meet these
E468 Practice for Presentation of Constant Amplitude Fa-
macroscopic behaviour assumptions. Generally, continuous
tigue Test Results for Metallic Materials
fibre-reinforced ceramic composites (CFCCs) do not macro-
E739 Practice for Statistical Analysis of Linear or Linear-
scopically exhibit isotropic, homogeneous, continuous behav-
ized Stress-Life ( S-N) and Strain-Life (e-N) Fatigue Data
iour and application of this practice to these materials is not
E1012 PracticeforVerificationofTestFrameandSpecimen
recommended.
Alignment Under Tensile and Compressive Axial Force
1.3 The values stated in SI units are to be regarded as the
Application
standard and are in accordance with IEEE/ASTM SI 10.
E1823 Terminology Relating to Fatigue and Fracture Test-
1.4 This standard does not purport to address all of the
ing
safety concerns, if any, associated with its use. It is the
IEEE/ASTM SI 10 Standard for Use of the International
responsibility of the user of this standard to establish appro-
System of Units (SI) (The Modern Metric System)
2.2 Military Handbook:
This practice is under the jurisdiction of ASTM Committee C28 on Advanced
Ceramics and is the direct responsibility of Subcommittee C28.01 on Mechanical
Properties and Performance. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved Feb. 1, 2007. Published March 2007. Originally contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
approved in 1996. Last previous edition approved in 2001 as C1361–01. DOI: Standards volume information, refer to the standard’s Document Summary page on
10.1520/C1361-01R07. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
C1361–01 (2007)
MIL-HDBK-790 Fractography and Characterization of 3.2.5.2 Discussion—Fluctuations may occur both in load
Fracture Origins in Advanced Structural Ceramics and with time (frequency) as in the case of random vibration.
3.2.6 cyclic fatigue life, N—thenumberofloadingcyclesof
f
3. Terminology
a specified character that a given test specimen sustains before
3.1 Definitions—Definitions of terms relating to advanced
failure of a specified nature occurs. (See Terminology E1823.)
–2
ceramics, cyclic fatigue, and tensile testing as they appear in
3.2.7 cyclic fatigue limit, S,[FL ], n—thelimitingvalueof
f
Terminology C1145, Terminology E1823, and Terminology
the median cyclic fatigue strength as the cyclic fatigue life, N,
f
6 7
E6, respectively, apply to the terms used in this practice.
becomes very large. (for example, N>10 -10 ). (See Terminol-
Selected terms with definitions non-specific to this practice
ogy E1823)
follow in 3.2 with the appropriate source given in parenthesis.
3.2.7.1 Discussion—Certain materials and environments
Terms specific to this practice are defined in 3.3.
preclude the attainment of a cyclic fatigue limit. Values
3.2 Definitions of Terms Non Specific to This Standard:
tabulated as cyclic fatigue limits in the literature are frequently
3.2.1 advanced ceramic, n—a highly engineered, high per-
(but not always) values of S at 50 % survival at N cycles of
f f
formance predominately non-metallic, inorganic, ceramic ma-
stress in which the mean stress, S , equals zero.
m
terial having specific functional attributes. (See Terminology –2
3.2.8 cyclic fatigue strength S , [FL ], n—the limiting
N
C1145.)
valueofthemediancyclicfatiguestrengthataparticularcyclic
–1
3.2.2 axial strain [LL ], n—the average longitudinal
fatigue life, N. (See Terminology E1823.)
f
strains measured at the surface on opposite sides of the
3.2.9 gage length, [L], n—the original length of that portion
longitudinal axis of symmetry of the test specimen by two
of the test specimen over which strain or change of length is
strain-sensing devices located at the mid length of the reduced
determined. (See Terminology E6.)
section. (See Practice E1012.)
–1 3.2.10 load ratio, n—in cyclic fatigue loading, the algebraic
3.2.3 bending strain [LL ], n—the difference between the
ratio of the two loading parameters of a cycle; the most widely
strainatthesurfaceandtheaxialstrain.Ingeneral,thebending
used ratios (see Terminology E1823):
strain varies from point to point around and along the reduced
minimum force valley force
section of the test specimen. (See Practice E1012.)
R 5 or R 5
maximum force peak force
3.2.4 constant amplitude loading, n—in cyclic fatigue load-
ing, a loading in which all peak loads are equal and all of the
and:
valley forces are equal. (See Terminology E1823.)
force amplitude ~maximum force – minimum force!
3.2.5 cyclic fatigue, n—the process of progressive localized
A5 orA5
mean force ~maximum force 1 minimum force!
permanent structural change occurring in a material subjected
–2
3.2.11 modulus of elasticity [FL ], n—the ratio of stress to
to conditions that produce fluctuating stresses and strains at
corresponding strain below the proportional limit. (See Termi-
some point or points and that may culminate in cracks or
nology E6.)
complete fracture after a sufficient number of fluctuations. (See
Terminology E1823.) See Fig. 1 for nomenclature relevant to 3.2.12 percent bending, n—the bending strain times 100
cyclic fatigue testing. divided by the axial strain. (See Practice E1012.)
3.2.5.1 Discussion—In glass technology static tests of con-
3.2.13 S-N diagram, n—a plot of stress versus the number
siderable duration are called static fatigue tests, a type of test
of cycles to failure. The stress can be maximum stress, S ,
max
generally designated as stress-rupture.
minimum stress, S , stress range, DS or S , or stress ampli-
min r
tude, S . The diagram indicates the S-N relationship for a
a
specified value of S , A, R and a specified probability of
m
survival. For N, a log scale is almost always used, although a
Available from Army Research Laboratory-Materials Directorate, Aberdeen
linear scale may also be used. For S, a linear scale is usually
Proving Ground, MD 21005.
used, although a log scale may also be used. (See Terminology
E1823 and Practice E468.)
3.2.14 slow crack growth, n—sub-critical crack growth
(extension) that may result from, but is not restricted to, such
mechanisms as environmentally-assisted stress corrosion or
diffusive crack growth.
–2
3.2.15 tensile strength [FL ], n—the maximum tensile
stress which a material is capable of sustaining. Tensile
strengthiscalculatedfromthemaximumforceduringatension
test carried to rupture and the original cross-sectional area of
the test specimen. (See Terminology E6.)
3.3 Definitions of Terms Specific to This Standard:
–2
3.3.1 maximum stress, S [FL ], n—the maximum ap-
max
plied stress during cyclic fatigue.
–2
3.3.2 mean stress, S [FL ], n—the average applied
max
FIG. 1 Cyclic Fatigue Nomenclature and Wave Forms stress during cyclic fatigue such that
C1361–01 (2007)
S 1 S
content, methods of test specimen preparation or fabrication-
max min
S 5 (1)
m
,test specimen conditioning, test environment, force or strain
–2
limits during cycling, wave shapes (that is, sinusoidal, trap-
3.3.3 minimum stress, S [FL ], n—the minimum applied
min
ezoidal, etc.), and failure mode. Some of these effects may be
stress during cyclic fatigue.
–2
consequences of stress corrosion or sub critical (slow) crack
3.3.4 stress amplitude, S [FL ], n—the difference between
a
growth which can be difficult to quantify. In addition, surface
the mean stress and the maximum or minimum stress such that
or near-surface flaws introduced by the test specimen fabrica-
S – S
max min
S 5 5 S – S 5 S – S (2)
tion process (machining) may or may not be quantifiable by
a max m m min
conventional measurements of surface texture. Therefore, sur-
–2
3.3.5 stress range, DSorS [FL ],, n—the difference be-
r
face effects (for example, as reflected in cyclic fatigue reduc-
tween the maximum stress and the minimum stress such that
tion factors as classified by Marin (3)) must be inferred from
DS = S = S – S
r max min
the results of numerous cyclic fatigue tests performed with test
3.3.6 time to cyclic fatigue failure, tf [t], n—total elapsed
specimens having identical fabrication histories.
timefromtestinitiationtotestterminationrequiredtoreachthe
4.6 The results of cyclic fatigue tests of specimens fabri-
number of cycles to failure.
cated to standardized dimensions from a particular material or
selected portions of a part, or both, may not totally represent
4. Significance and Use
the cyclic fatigue behavior of the entire, full-size end product
4.1 This practice may be used for material development,
or its in-service behavior in different environments.
material comparison, quality assurance, characterization, reli-
4.7 However, for quality control purposes, results derived
ability assessment, and design data generation.
from standardized tensile test specimens may be considered
4.2 High-strength, monolithic advanced ceramic materials
indicativeoftheresponseofthematerialfromwhichtheywere
are generally characterized by small grain sizes (<50 µm) and
taken for given primary processing conditions and post-
bulk densities near the theoretical density. These materials are
processing heat treatments.
candidates for load-bearing structural applications requiring
4.8 The cyclic fatigue behavior of an advanced ceramic is
high degrees of wear and corrosion resistance, and high-
dependent on its inherent resistance to fracture, the presence of
temperature strength. Although flexural test methods are com-
flaws, or damage accumulation processes, or both. There can
monly used to evaluate strength of advanced ceramics, the non
be significant damage in the test specimen without any visual
uniform stress distribution in a flexure specimen limits the
evidence such as the occurrence of a macroscopic crack. This
volume of material subjected to the maximum applied stress at
can result in a specific loss of stiffness and retained strength.
fracture. Uniaxially-loaded tensile strength tests may provide
Depending on the purpose for which the test is being con-
information on strength-limiting flaws from a greater volume
ducted, rather than final fracture, a specific loss in stiffness or
of uniformly stressed material.
retainedstrengthmayconstitutefailure.Incaseswherefracture
4.3 Cyclic fatigue by its nature is a probabilistic phenom-
occurs, analysis of fracture surfaces and fractography, though
enon as discussed in STP 91Aand STP 588.(1,2) In addition,
beyond the scope of this practice, are recommended.
the strengths of advanced ceramics are probabilistic in nature.
5. Interferences
Therefore, a sufficient number of test specimens at each testing
condition is required for statistical analysis and design, with 5.1 Test environment (vacuum, inert gas, ambient air, etc.)
guidelines for sufficient numbers provided in STP 91A, (1) including moisture content (for example, relative humidity)
STP 588, (2) and Practice E739. The many different tensile mayhaveaninfluenceonthemeasuredcyclicfatiguebehavior.
specimen geometries available for cyclic fatigue testing may In particular, the behavior of materials susceptible to slow
result in variations in the measured cyclic fatigue behavior of crack growth fracture will be strongly influenced by test
aparticularmaterialduetodifferencesinthevolumeorsurface environment and testing rate. Conduct tests to evaluate the
area of material in the gage section of the test specimens.
mechanical cyclic fatigue behaviour of a material in inert
4.4 Tensile cyclic fatigue tests provide information on the environments to minimize slow crack growth effects. Con-
material response under fluctuating uniaxial tensile stresses.
versely, conduct tests in environments or at test modes and
Uniform stress states are required to effectively evaluate any rates representative of service conditions to evaluate material
non-linear stress-strain behavior which may develop as the performance under use conditions, or both. Regardless of
result of cumulative damage processes (for example, microc- whether testing is conducted in uncontrolled ambient air or
racking, cyclic fatigue crack growth, etc.). controlled environments, monitor and report relative humidity
4.5 Cumulative damage processes due
...