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ASTM E468/E468M-23a

(Practice)

Standard Practice for Presentation of Constant Amplitude Fatigue Test Results for Metallic Materials

Standard Practice for Presentation of Constant Amplitude Fatigue Test Results for Metallic Materials

SIGNIFICANCE AND USE
4.1 Fatigue test results may be significantly influenced by the properties and history of the parent material, the operations performed during the preparation of the fatigue specimens, and the testing machine and test procedures used during the generation of the data. The presentation of fatigue test results should include citation of basic information on the material, specimens, and testing to increase the utility of the results and to reduce to a minimum the possibility of misinterpretation or improper application of those results.
SCOPE
1.1 This practice covers the desirable and minimum information to be communicated between the originator and the user of data derived from constant-force amplitude axial, bending, or torsion fatigue tests of metallic materials tested in air and at room temperature.  
Note 1: Practice E466, although not directly referenced in the text, is considered important enough to be listed in this standard.  
1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

Status
Published
Publication Date
31-Oct-2023
ICS
77.040.10 - Mechanical testing of metals
Technical Committee
E08 - Fatigue and Fracture
Drafting Committee
E08.05 - Cyclic Deformation and Fatigue Crack Formation
Current Stage
Ref Project

Relations

Replaces
ASTM E468/E468M-23 - Standard Practice for Presentation of Constant Amplitude Fatigue Test Results for Metallic Materials
Effective Date
01-Nov-2023

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Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: E468/E468M − 23a
Standard Practice for
Presentation of Constant Amplitude Fatigue Test Results for
1
Metallic Materials
This standard is issued under the fixed designation E468/E468M; 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 E466 Practice for Conducting Force Controlled Constant
Amplitude Axial Fatigue Tests of Metallic Materials
1.1 This practice covers the desirable and minimum infor-
E467 Practice for Verification of Constant Amplitude Dy-
mation to be communicated between the originator and the user
namic Forces in an Axial Fatigue Testing System
of data derived from constant-force amplitude axial, bending,
E739 Guide for Statistical Analysis of Linear or Linearized
or torsion fatigue tests of metallic materials tested in air and at
Stress-Life (S-N) and Strain-Life (ε-N) Fatigue Data
room temperature.
3
(Withdrawn 2024)
NOTE 1—Practice E466, although not directly referenced in the text, is
E1823 Terminology Relating to Fatigue and Fracture Testing
considered important enough to be listed in this standard.
2.2 Special Technical Publications:
1.2 The values stated in either SI units or inch-pound units
STP 91–A A Guide for Fatigue Testing and the Statistical
4
are to be regarded separately as standard. The values stated in
Analysis of Fatigue Data
5
each system are not necessarily exact equivalents; therefore, to
STP 588 Manual on Statistical Planning and Analysis
ensure conformance with the standard, each system shall be
3. Terminology Definitions and Nomenclature
used independently of the other, and values from the two
systems shall not be combined.
3.1 The terms and abbreviations used in this practice are
1.3 This standard does not purport to address all of the defined in Terminology E6 and in Terminology E1823.
safety concerns, if any, associated with its use. It is the
4. Significance and Use
responsibility of the user of this standard to establish appro-
priate safety, health, and environmental practices and deter-
4.1 Fatigue test results may be significantly influenced by
mine the applicability of regulatory limitations prior to use.
the properties and history of the parent material, the operations
1.4 This international standard was developed in accor-
performed during the preparation of the fatigue specimens, and
dance with internationally recognized principles on standard-
the testing machine and test procedures used during the
ization established in the Decision on Principles for the
generation of the data. The presentation of fatigue test results
Development of International Standards, Guides and Recom-
should include citation of basic information on the material,
mendations issued by the World Trade Organization Technical
specimens, and testing to increase the utility of the results and
Barriers to Trade (TBT) Committee.
to reduce to a minimum the possibility of misinterpretation or
improper application of those results.
2. Referenced Documents
5. Listing of Basic Information About Fatigue Test
2
2.1 ASTM Standards:
Specimen
E6 Terminology Relating to Methods of Mechanical Testing
5.1 Specification and Properties of Material:
E8/E8M Test Methods for Tension Testing of Metallic Ma-
5.1.1 Material Prior to Fatigue Test Specimen
terials
Preparation—The minimum information to be presented
should include the designation or specification (for example,
A441, SAE 1070, and so forth) or proprietary grade; form of
1
This practice is under the jurisdiction of ASTM Committee E08 on Fatigue and
product (for example, plate, bar, casting, and so forth); heat
Fracture and is the direct responsibility of E08.05 E08.05 on Cyclic Deformation
number; melting practice; last mechanical working and last
and Fatigue Crack Formation.
Current edition approved Nov. 1, 2023. Published January 2024. Originally
approved in 1972. Last previous edition approved in 2023 as E468/E468M –23.
3
DOI: 10.1520/E0468_E0468M-23A. The last approved version of this historical standard is referenced on
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or www.astm.org.
4
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM A Guide for Fatigue Testing and the Statistical Analysis of Fatigue Data,
Standards volume information, refer to the standard’s Document Summary page on ASTM International, 1963.
5
the ASTM website. Manual on Statistical Planning and Analysis, ASTM International, 1975.,
Copyright © ASTM Inte
...

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. Because
it 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 version
of the standard as published by ASTM is to be considered the official document.
Designation: E468/E468M − 23 E468/E468M − 23a
Standard Practice for
Presentation of Constant Amplitude Fatigue Test Results for
1
Metallic Materials
This standard is issued under the fixed designation E468/E468M; 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
1.1 This practice covers the desirable and minimum information to be communicated between the originator and the user of data
derived from constant-force amplitude axial, bending, or torsion fatigue tests of metallic materials tested in air and at room
temperature.
NOTE 1—Practice E466, although not directly referenced in the text, is considered important enough to be listed in this standard.
1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each
system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used
independently of the other, and values from the two systems shall not be combined.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of
regulatory limitations prior to use.
1.4 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2
2.1 ASTM Standards:
E6 Terminology Relating to Methods of Mechanical Testing
E8/E8M Test Methods for Tension Testing of Metallic Materials
E466 Practice for Conducting Force Controlled Constant Amplitude Axial Fatigue Tests of Metallic Materials
E467 Practice for Verification of Constant Amplitude Dynamic Forces in an Axial Fatigue Testing System
E739 Guide for Statistical Analysis of Linear or Linearized Stress-Life (S-N) and Strain-Life (ε-N) Fatigue Data (Withdrawn
3
2024)
E1823 Terminology Relating to Fatigue and Fracture Testing
1
This practice is under the jurisdiction of ASTM Committee E08 on Fatigue and Fracture and is the direct responsibility of E08.05 E08.05 on Cyclic Deformation and
Fatigue Crack Formation.
Current edition approved May 15, 2023Nov. 1, 2023. Published June 2023January 2024. Originally approved in 1972. Last previous edition approved in 20182023 as
E468E468/E468M —18. DOI: 10.1520/E0468_E0468M-23. –23. DOI: 10.1520/E0468_E0468M-23A.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
3
The last approved version of this historical standard is referenced on www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
E468/E468M − 23a
2.2 Special Technical Publications:
4
STP 91–A A Guide for Fatigue Testing and the Statistical Analysis of Fatigue Data
5
STP 588 Manual on Statistical Planning and Analysis
3. Terminology Definitions and Nomenclature
3.1 The terms and abbreviations used in this practice are defined in Terminology E6 and in Terminology E1823.
4. Significance and Use
4.1 Fatigue test results may be significantly influenced by the properties and history of the parent material, the operations
performed during the preparation of the fatigue specimens, and the testing machine and test procedures used during the generation
of the data. The presentation of fatigue test results should include citation of basic information on the material, specimens, and
testing to increase the utility of the results and to reduce to a minimum the possibility of misinterpretation or improper application
of those results.
5. Listing of Basic Information About Fatigue Test Specimen
5.1 Specification and Properties of Material:
5.1.1 Material Prior to Fatigue Test Specimen Preparation—The minimum information to be presented should include the
designation or specification (for example,
...

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6.1 Creep crack growth rate expressed as a function of the steady state C* or K characterizes the resistance of a material to crack growth under conditions of extensive creep deformation or under brittle creep conditions. Background information on the rationale for employing the fracture mechanics approach in the analyses of creep crack growth data is given in (11, 13, 30-35).  
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1.1 This test method covers the determination of creep crack initiation (CCI) and creep crack growth (CCG) in metals at elevated temperatures using pre-cracked specimens subjected to static or quasi-static loading conditions. The solutions presented in this test method are validated for base material (that is, homogenous properties) and mixed base/weld material with inhomogeneous microstructures and creep properties. The CCI time, t0.2, which is the time required to reach an initial crack extension of δai = 0.2 mm to occur from the onset of first applied force, and CCG rate, a˙  or da/dt are expressed in terms of the magnitude of creep crack growth correlated by fracture mechanics parameters, C* or K, with C* defined as the steady state determination of the crack tip stresses derived in principal from C*(t) and Ct   (1-17).2 The crack growth derived in this manner is identified as a material property which can be used in modeling and life assessment methods (17-28).  
1.1.1 The choice of the crack growth correlating parameter C*, C*(t), Ct, or K depends on the material creep properties, geometry and size of the specimen. Two types of material behavior are generally observed during creep crack growth tests; creep-ductile (1-17) and creep-brittle (29-44). In creep ductile materials, where creep strains dominate and creep crack growth is accompanied by substantial time-dependent creep strains at the crack tip, the crack growth rate is correlated by the steady state definitions of Ct or C*(t) , defined as C* (see 1.1.4). In creep-brittle materials, creep crack growth occurs at low creep ductility. Consequently, the time-dependent creep strains are comparable to or dominated by accompanying elastic strains local to the crack tip. Under such steady state creep-brittle conditions, Ct or K could be chosen as the correlating parameter (8-14).  
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ASTM E740/E740M-23(Practice)
Standard Practice for Fracture Testing with Surface-Crack Tension Specimens

SIGNIFICANCE AND USE
4.1 The surface-crack tension (SCT) test is used to estimate the load-carrying capacity of simple sheet- or plate-like structural components having a type of flaw likely to occur in service. The test is also used for research purposes to investigate failure mechanisms of cracks under service conditions.  
4.2 The residual strength of an SCT specimen is a function of the crack depth and length and the specimen thickness as well as the characteristics of the material. This relationship is extremely complex and cannot be completely described or characterized at present.  
4.2.1 The results of the SCT test are suitable for direct application to design only when the service conditions exactly parallel the test conditions. Some methods for further analysis are suggested in Appendix X1.  
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1.1 This practice covers the design, preparation, and testing of surface-crack tension (SCT) specimens. It relates specifically to testing under continuously increasing force and excludes cyclic and sustained loadings. The quantity determined is the residual strength of a specimen having a semielliptical or circular-segment fatigue crack in one surface. This value depends on the crack dimensions and the specimen thickness as well as the characteristics of the material.  
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1.3 This practice is limited to specimens having a uniform rectangular cross section in the test section. The test section width and length must be large with respect to the crack length. Crack depth and length should be chosen to suit the ultimate purpose of the test.  
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Note 1: Further information on background and need for this type of test is given in the report of ASTM Task Group E24.01.05 on Part-Through-Crack Testing (1).2  
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Standard Test Method for Determining Plane-Strain Crack-Arrest Fracture Toughness, KIa, of Ferritic Steels

SIGNIFICANCE AND USE
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ASTM E1820-23b(Test Method)
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5.1 Assuming the presence of a preexisting, sharp, fatigue crack, the material fracture toughness values identified by this test method characterize its resistance to: (1)  fracture of a stationary crack, (2) fracture after some stable tearing, (3) stable tearing onset, and (4) sustained stable tearing. This test method is particularly useful when the material response cannot be anticipated before the test. Application of procedures in Test Method E1921 is recommended for testing ferritic steels that undergo cleavage fracture in the ductile-to-brittle transition.  
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5.2 The following cautionary statements are based on some observations.  
5.2.1 Particular care must be exercised in applying to structural flaw tolerance assessment the fracture toughness value associated with fracture after some stable tearing has occurred. This response is characteristic of ferritic steel in the transition regime. This response is especially sensitive to material inhomogeneity and to constraint variations that may be induced by planar geometry, thickness differences, mode of loading, and structural details.  
5.2.2 The J-R curve from bend-type specimens recommended by this test method (SE(B), C(T), and DC(T)) has been observed to be conservative with respect to results from tensile loading configurations.  
5.2.3 The values of δc, δu, Jc, and Ju  may be affected by specimen dimensions.
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1.1 This test method covers procedures and guidelines for the determination of fracture toughness of metallic materials using the following parameters: K, J, and CTOD (δ). Toughness can be measured in the R-curve format or as a point value. The fracture toughness determined in accordance with this test method is for the opening mode (Mode I) of loading.
Note 1: Until this version, KIc could be evaluated using this test method as well as by using Test Method E399. To avoid duplication, the evaluation of KIc has been removed from this test method and the user is referred to Test Method E399.  
1.2 The recommended specimens are single-edge bend, [SE(B)], compact, [C(T)], and disk-shaped compact, [DC(T)]. All specimens contain notches that are sharpened with fatigue cracks.  
1.2.1 Specimen dimensional (size) requirements vary according to the fracture toughness analysis applied. The guidelines are established through consideration of material toughness, material flow strength, and the individual qualification requirements of the toughness value per values sought.  
Note 2: Other standard methods for the determination of fracture toughness using the parameters K, J, and CTOD are contained in Test Methods E399, E1290, and E1921. This test method was developed to provide a common method for determining all applicable toughness parameters from a single test.  
1.3 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations iss...

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ASTM E647-23a(Test Method)
Standard Test Method for Measurement of Fatigue Crack Growth Rates

SIGNIFICANCE AND USE
5.1 Fatigue crack growth rate expressed as a function of crack-tip stress-intensity factor range, da/dN versus ΔK, characterizes a material's resistance to stable crack extension under cyclic loading. Background information on the ration-ale for employing linear elastic fracture mechanics to analyze fatigue crack growth rate data is given in Refs (3) and (4).  
5.1.1 In innocuous (inert) environments fatigue crack growth rates are primarily a function of ΔK and force ratio, R, or Kmax and R (Note 1). Temperature and aggressive environments can significantly affect da/dN versus ΔK, and in many cases accentuate R-effects and introduce effects of other loading variables such as cycle frequency and waveform. Attention needs to be given to the proper selection and control of these variables in research studies and in the generation of design data.
Note 1: ΔK, Kmax, and R are not independent of each other. Specification of any two of these variables is sufficient to define the loading condition. It is customary to specify one of the stress-intensity parameters (ΔK or Kmax) along with the force ratio, R.  
5.1.2 Expressing da/dN as a function of ΔK provides results that are independent of planar geometry, thus enabling exchange and comparison of data obtained from a variety of specimen configurations and loading conditions. Moreover, this feature enables da/dN versus ΔK data to be utilized in the design and evaluation of engineering structures. The concept of similitude is assumed, which implies that cracks of differing lengths subjected to the same nominal ΔK will advance by equal increments of crack extension per cycle.  
5.1.3 Fatigue crack growth rate data are not always geometry-independent in the strict sense since thickness effects sometimes occur. However, data on the influence of thickness on fatigue crack growth rate are mixed. Fatigue crack growth rates over a wide range of ΔK have been reported to either increase, decrease, or remain unaffected as specimen...
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1.1 This test method2 covers the determination of fatigue crack growth rates from near-threshold (see region I in Fig. 1) to Kmax  controlled instability (see region III in Fig. 1.) Results are expressed in terms of the crack-tip stress-intensity factor range (ΔK), defined by the theory of linear elasticity.  
1.9 Special requirements for the various specimen configurations appear in the following order:
The Compact Specimen  
Annex A1  
The Middle Tension Specimen  
Annex A2  
The Eccentrically-Loaded Single Edge Crack Tension Specimen  
Annex A3  
1.10 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.11 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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ASTM
ASTM E561-23(Test Method)
Standard Test Method for KR Curve Determination

SIGNIFICANCE AND USE
5.1 The KR curve characterizes the resistance to fracture of materials during slow, stable crack extension and results from the growth of the plastic zone ahead of the crack as it extends from a fatigue precrack or sharp notch. It provides a record of the toughness development as a crack is driven stably under increasing applied stress intensity factor K. For a given material, KR curves are dependent upon specimen thickness, temperature, and strain rate. The amount of valid KR data generated in the test depends on the specimen type, size, method of loading, and, to a lesser extent, testing machine characteristics.  
5.2 For an untested geometry, the KR curve can be matched with the applied-K curves (crack driving curves) to estimate the degree of stable crack extension and the conditions necessary to cause unstable crack propagation (2). In making this estimate, KR curves are regarded as being independent of initial crack size ao and the specimen configuration in which they are developed. For a given material, material thickness, and test temperature, KR curves appear to be a function of only the effective crack extension Δae (3).  
5.2.1 To predict crack behavior and instability in a component, a family of applied-K curves is generated by calculating  K as a function of crack size for the component using a series of force, displacement, or combined loading conditions. The KR curve may be superimposed on the family of applied-K curves as shown in Fig. 1, with the origin of the KR curve coinciding with the assumed initial crack size ao. The intersection of the applied-K curves with the KR curve shows the expected effective stable crack extension for each loading condition. The applied-K curve that develops tangency with the KR curve defines the critical loading condition that will cause the onset of unstable fracture under the loading conditions used to develop the applied-K curves.
FIG. 1 Schematic Representation of KR curve and Applied K Curves to Predict Insta...
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1.1 This test method covers the determination of the resistance to fracture of metallic materials under Mode I loading at static rates using either of the following notched and precracked specimens: the middle-cracked tension M(T) specimen or the compact tension C(T) specimen. A KR curve is a continuous record of toughness development (resistance to crack extension) in terms of KR plotted against crack extension in the specimen as a crack is driven under an increasing stress intensity factor, K. (1)2  
1.2 Materials that can be tested for KR curve development are not limited by strength, thickness, or toughness, so long as specimens are of sufficient size to remain predominantly elastic to the effective crack extension value of interest.  
1.3 Specimens of standard proportions are required, but size is variable, to be adjusted for yield strength and toughness of the materials.  
1.4 Only two of the many possible specimen types that could be used to develop KR curves are covered in this method.  
1.5 The test is applicable to conditions where a material exhibits slow, stable crack extension under increasing crack driving force, which may exist in relatively tough materials under plane stress crack tip conditions.  
1.6 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.  
1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Reco...

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ASTM
ASTM E2789-10(2021)(Guide)
Standard Guide for Fretting Fatigue Testing

SIGNIFICANCE AND USE
4.1 Fretting fatigue tests are used to determine the effects of several fretting parameters on the fatigue lives of metallic materials. Some of these parameters include differing materials, relative displacement amplitudes, normal force at the fretting contact, alternating tangential force, the contact geometry, surface integrity parameters such as finish, and the environment. Comparative tests are used to determine the effectiveness of palliatives on the fatigue life of specimens with well-controlled boundary conditions so that the mechanics of the fretting fatigue test can be modeled. Generally, it is useful to compare the fretting fatigue response to plain fatigue to obtain knockdown or reduction factors from fretting fatigue. The results may be used as a guide in selecting material combinations, design stress levels, lubricants, and coatings to alleviate or eliminate fretting fatigue concerns in new or existing designs. However, due to the synergisms of fatigue, wear, and corrosion on the fretting fatigue parameters, extreme care should be exercised in the judgment to determine if the test conditions meet the design or system conditions.  
4.2 For data to be comparable, reproducible, and correlated amongst laboratories and relevant to mimic fretting in an application, all parameters critical to the fretting fatigue life of the material in question will need to be replicated. Because alterations in environment, metallurgical properties, fretting loading (controlled forces and displacements), compliance of the test system, etc. can affect the response, no general guidelines exist to quantitatively ascertain what the effect will be on the specimen fretting fatigue life if a single parameter is varied. To assure test results can be correlated and reproduced, all material variables, testing information, physical procedures, and analytical procedures should be reported in a manner that is consistent with good current test practices.  
4.3 Because of the wear phenome...
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1.1 This guide defines terminology and covers general requirements for conducting fretting fatigue tests and reporting the results. It describes the general types of fretting fatigue tests and provides some suggestions on developing and conducting fretting fatigue test programs.  
1.2 Fretting fatigue tests are designed to determine the effects of mechanical and environmental parameters on the fretting fatigue behavior of metallic materials. This guide is not intended to establish preference of one apparatus or specimen design over others, but will establish guidelines for adherence in the design, calibration, and use of fretting fatigue apparatus and recommend the means to collect, record, and reporting of the data.  
1.3 The number of cycles to form a fretting fatigue crack is dependent on both the material of the fatigue specimen and fretting pad, the geometry of contact between the two, and the method by which the loading and displacement are imposed. Similar to wear behavior of materials, it is important to consider fretting fatigue as a system response, instead of a material response. Because of this dependency on the configuration of the system, quantifiable comparisons of various material combinations should be based on tests using similar fretting fatigue configurations and material couples.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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ASTM
ASTM E606/E606M-21(Test Method)
Standard Test Method for Strain-Controlled Fatigue Testing

SIGNIFICANCE AND USE
4.1 Strain-controlled fatigue is a phenomenon that is influenced by the same variables that influence force-controlled fatigue. The nature of strain-controlled fatigue imposes distinctive requirements on fatigue testing methods. In particular, cyclic total strain should be measured and cyclic plastic strain should be determined. Furthermore, either of these strains typically is used to establish cyclic limits; total strain usually is controlled throughout the cycle. The uniqueness of this test method and the results it yields are the determination of cyclic stresses and strains at any time during the tests. Differences in strain histories other than constant-amplitude alter fatigue life as compared with the constant amplitude results (for example, periodic overstrains and block or spectrum histories). Likewise, the presence of nonzero mean strains and varying environmental conditions may alter fatigue life as compared with the constant-amplitude, fully reversed fatigue tests. Care must be exercised in analyzing and interpreting data for such cases. In the case of variable amplitude or spectrum strain histories, cycle counting can be performed with Practice E1049.  
4.2 Strain-controlled fatigue can be an important consideration in the design of industrial products. It is important for situations in which components or portions of components undergo either mechanically or thermally induced cyclic plastic strains that cause failure within relatively few (that is, approximately 5) cycles. Information obtained from strain-controlled fatigue testing may be an important element in the establishment of design criteria to protect against component failure by fatigue.  
4.3 Strain-controlled fatigue test results are useful in the areas of mechanical design as well as materials research and development, process and quality control, product performance, and failure analysis. Results of a strain-controlled fatigue test program may be used in the formulation of empirical relat...
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1.1 This test method covers the determination of fatigue properties of nominally homogeneous materials by the use of test specimens subjected to uniaxial forces. It is intended as a guide for fatigue testing performed in support of such activities as materials research and development, mechanical design, process and quality control, product performance, and failure analysis. While this test method is intended primarily for strain-controlled fatigue testing, some sections may provide useful information for force-controlled or stress-controlled testing.  
1.2 The use of this test method is limited to specimens and does not cover testing of full-scale components, structures, or consumer products.  
1.3 This test method is applicable to temperatures and strain rates for which the magnitudes of time-dependent inelastic strains are on the same order or less than the magnitudes of time-independent inelastic strains. No restrictions are placed on environmental factors such as temperature, pressure, humidity, medium, and others, provided they are controlled throughout the test, do not cause loss of or change in dimension with time, and are detailed in the data report.  
Note 1: The term inelastic is used herein to refer to all nonelastic strains. The term plastic is used herein to refer only to the time-independent (that is, noncreep) component of inelastic strain. To truly determine a time-independent strain the force would have to be applied instantaneously, which is not possible. A useful engineering estimate of time-independent strain can be obtained when the strain rate exceeds some value. For example, a strain rate of 1 × 10−3 sec−1  is often used for this purpose. This value should increase with increasing test temperature.  
1.4 This test method is restricted to the testing of uniform gage section test specimens subjected to axial forces as shown in Fig. 1(a). Testing is limited to strain-controlled cycling. The test ...

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ASTM
ASTM E466-21(Practice)
Standard Practice for Conducting Force Controlled Constant Amplitude Axial Fatigue Tests of Metallic Materials

SIGNIFICANCE AND USE
4.1 The axial force fatigue test is used to determine the effect of variations in material, geometry, surface condition, stress, and so forth, on the fatigue resistance of metallic materials subjected to direct stress for relatively large numbers of cycles. The results may also be used as a guide for the selection of metallic materials for service under conditions of repeated direct stress.  
4.2 In order to verify that such basic fatigue data generated using this practice is comparable, reproducible, and correlated among laboratories, it may be advantageous to conduct a round-robin-type test program from a statistician's point of view. To do so would require the control or balance of what are often deemed nuisance variables; for example, hardness, cleanliness, grain size, composition, directionality, surface residual stress, surface finish, and so forth. Thus, when embarking on a program of this nature it is essential to define and maintain consistency a priori, as many variables as reasonably possible, with as much economy as prudent. All material variables, testing information, and procedures used should be reported so that correlation and reproducibility of results may be attempted in a fashion that is considered reasonably good current test practice.  
4.3 The results of the axial force fatigue test are suitable for application to design only when the specimen test conditions realistically simulate service conditions or some methodology of accounting for service conditions is available and clearly defined.
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1.1 This practice covers the procedure for the performance of axial force controlled fatigue tests to obtain the fatigue strength of metallic materials in the fatigue regime where the strains are predominately elastic, both upon initial loading and throughout the test. This practice is limited to the fatigue testing of axial unnotched and notched specimens subjected to a constant amplitude, periodic forcing function in air at room temperature.  
1.2 The use of this test method is limited to specimens and does not cover testing of full-scale components, structures, or consumer products.  
1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.  
1.4 The text of this standard references notes and footnotes that provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the standard.
Note 1: The following documents, although not directly referenced in the text, are considered important enough to be listed in this practice:
E739 Practice for Statistical Analysis of Linear or Linearized Stress-Life (S-N) and Strain-Life (ε-N) Fatigue Data
STP 566 Handbook of Fatigue Testing2
STP 588 Manual on Statistical Planning and Analysis for Fatigue Experiments3
STP 731 Tables for Estimating Median Fatigue Limits4  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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