ISO/TC 164/SC 4 - Fatigue, fracture and toughness testing

This document applies to stress and/or force-controlled thermo-mechanical fatigue (TMF) testing. Both forms of control, force or stress, can be applied according to this document. This document describes the equipment, specimen preparation, and presentation of the test results in order to determine TMF properties.

This document specifies the conditions for performing torsional, constant-amplitude, nominally elastic stress fatigue tests on metallic specimens without deliberately introducing stress concentrations. The tests are typically carried out at ambient temperature or an elevated temperature in air by applying a pure couple to the specimen about its longitudinal axis. While the form, preparation and testing of specimens of circular cross-section and tubular cross-section are described in this document, component and other specialized types of testing are not included. Similarly, low-cycle torsional fatigue tests carried out under constant-amplitude angular displacement control, which lead to failure in a few thousand cycles, are also excluded.

This document specifies the method for rotating bar bending fatigue testing of metallic materials. The tests are conducted at room temperature or elevated temperature in air, the specimen being rotated. Fatigue tests on notched specimens are not covered by this document, since the shape and size of notched specimens have not been standardized. However, fatigue test procedures described in this document can be applied to fatigue tests of notched specimens.

This document specifies methods for determining fracture toughness in terms of K, δ, J and R-curves for homogeneous metallic materials subjected to quasistatic loading. Specimens are notched, precracked by fatigue and tested under slowly increasing displacement. The fracture toughness is determined for individual specimens at or after the onset of ductile crack extension or at the onset of ductile crack instability or unstable crack extension. In cases where cracks grow in a stable manner under ductile tearing conditions, a resistance curve describing fracture toughness as a function of crack extension is measured. In some cases in the testing of ferritic materials, unstable crack extension can occur by cleavage or ductile crack initiation and growth, interrupted by cleavage extension. The fracture toughness at crack arrest is not covered by this document. Special testing requirements and analysis procedures are necessary when testing weldments, and these are described in ISO 15653 which is complementary to this document. Statistical variability of the results strongly depends on the fracture type, for instance, fracture toughness associated with cleavage fracture in ferritic steels can show large variation. For applications that require high reliability, a statistical approach can be used to quantify the variability in fracture toughness in the ductile-to-brittle transition region, such as that given in ASTM E1921. However, it is not the purpose of this document to specify the number of tests to be carried out nor how the results of the tests are to be applied or interpreted.

This document specifies the conditions for conducting the plane bending fatigue test on an axial machine, constant-amplitude, force or displacement controlled, at room temperature (ideally between 10 °C and 35 °C) on metallic specimens, without deliberately introduced stress concentrations. This document does not include the reversed/partially loading test. The purpose of the test is to provide relevant results, such as the relation between applied stress and number of cycles to failure for a given material condition, expressed by hardness and microstructure, at various stress ratios. Although the shape, preparation and testing of specimens of rectangular and bevelled cross-section are specified, component testing and other specialized forms of testing are not included in this document. Fatigue tests on notched specimens are not covered by this document since the shape and size of notched test pieces have not been specified in any standard so far. Guidelines are given in Annex A. However, the fatigue-test procedures described in this document can be used for testing such notched specimens. It is possible for the results of a fatigue test to be affected by atmospheric conditions. Where controlled conditions are required, ISO 554:1976, 2.1 applies.

This document specifies a test method for the determination of brittle crack arrest toughness. It is applicable to ferritic steel base metals exhibiting ductile to brittle transition behaviour. Applicable materials are rolled steel plates. It is intended for materials with a tensile strength of 950 MPa or less and a test piece thickness of 200 mm or less. The range of arrest temperatures is between −196 °C and +100 °C. This document can be applied to flat rolled steel plates but not to flattened steel pipes because the flattening can cause changes in arrest toughness.

This document describes tests for determining the fatigue crack growth rate from the fatigue crack growth threshold stress-intensity factor range, ΔKth, to the onset of rapid, unstable fracture. This document is primarily intended for use in evaluating isotropic metallic materials under predominantly linear-elastic stress conditions and with force applied only perpendicular to the crack plane (mode I stress condition), and with a constant force ratio, R.

ISO/TR 12112:2018 discusses the general principles of multiaxial fatigue testing and the design recommendations for specific classes of multiaxial testing machines and test specimens.

ISO 15653:2018 specifies methods for determining fracture toughness in terms of stress intensity factor (K), crack tip opening displacement or CTOD (δ) and experimental equivalent of the J-integral for welds in metallic materials (J). ISO 15653:2018 complements ISO 12135, which covers all aspects of fracture toughness testing of parent metal and which needs to be used in conjunction with this document. This document describes methods for determining point values of fracture toughness. It should not be considered a way of obtaining a valid R-curve (resistance-to-crack-extension curve). However, the specimen preparation methods described in this document could be usefully employed when determining R-curves for welds. The methods use fatigue precracked specimens which have been notched, after welding, in a specific target area in the weld. Methods are described to evaluate the suitability of a weld for notch placement within the target area, which is either within the weld metal or within the weld heat-affected zone (HAZ), and then, where appropriate, to evaluate the effectiveness of the fatigue crack in sampling these areas.

ISO 1099:2017 specifies the conditions for conducting axial, constant-amplitude, force-controlled, fatigue tests at ambient temperature on metallic specimens, without deliberately introduced stress concentrations. The object of testing while employing this document is to provide fatigue information, such as the relation between applied stress and number of cycles to failure for a given material condition, such as hardness and microstructure, at various stress ratios. While the form, preparation and testing of specimens of circular and rectangular cross-section are described, component testing and other specialized forms of testing are not included in this document.

ISO 12106:2017 specifies a method of testing uniaxially deformed specimens under strain control at constant amplitude, uniform temperature and fixed strain ratios including at Re = −1 for the determination of fatigue properties. It can also be used as a guide for testing under other R-ratios, as well as elevated temperatures where creep deformation effects may be active.

ISO 148-1:2016 specifies the Charpy (V-notch and U-notch) pendulum impact test method for determining the energy absorbed in an impact test of metallic materials. This part of ISO 148 does not cover instrumented impact testing, which is specified in ISO 14556. Annexes B and C are based on ASTM E23 and are used with the permission of ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959, USA.

ISO 148-2:2016 covers the verification of pendulum-type impact testing machines, in terms of their constructional elements, their overall performance and the accuracy of the results they produce. It is applicable to machines with 2 mm or 8 mm strikers used for pendulum impact tests carried out, for instance, in accordance with ISO 148‑1. It can be applied to pendulum impact testing machines of various capacities and of different design. Impact machines used for industrial, general or research laboratory testing of metallic materials in accordance with this part of ISO 148 are referred to as industrial machines. Those with more stringent requirements are referred to as reference machines. Specifications for the verification of reference machines are found in ISO 148‑3. ISO 148-2:2016 describes two methods of verification. a) The direct method, which is static in nature, involves measurement of the critical parts of the machine to ensure that it meets the requirements of this part of ISO 148. Instruments used for the verification and calibration are traceable to national or international standards. b) The indirect method, which is dynamic in nature, uses reference test pieces to verify points on the measuring scale for absorbed energy. The requirements for the reference test pieces are found in ISO 148‑3. A pendulum impact testing machine is not in compliance with this part of ISO 148 until it has been verified by both the direct and indirect methods and meets the requirements of Clause 6 and Clause 7. ISO 148-2:2016 describes how to assess the different components of the total energy absorbed in fracturing a test piece. This total absorbed energy consists of - the energy needed to fracture the test piece itself, and - the internal energy losses of the pendulum impact testing machine performing the first half-cycle swing from the initial position. NOTE Internal energy losses are due to the following: - air resistance, friction of the bearings of the rotation axis and of the indicating pointer of the pendulum which can be determined by the direct method (see 6.4.5); - shock of the foundation, vibration of the frame and pendulum for which no suitable measuring methods and apparatus have been developed.

ISO 148-3:2016 specifies the requirements, preparation and methods for qualifying test pieces used for the indirect verification of pendulum impact testing machines in accordance with ISO 148‑2. It specifies notched test pieces with nominal dimensions identical to those specified in ISO 148‑1; however, the tolerances are more stringent. NOTE 1 The chemical composition or heat treatment, or both, are varied according to the energy level desired. NOTE 2 Reference test pieces are qualified on reference pendulum impact testing machines which are also described in this part of ISO 148.

In fracture assessments of steel structures containing cracks, it has generally been assumed that the fracture resistance of fracture toughness specimens is equal to the fracture resistance of structural components. However, such an assumption often leads to excessively conservative fracture assessments. This is due to a loss of plastic constraint in structural components, which are subjected mainly to tensile loading. By contrast, fracture toughness specimens hold a constrained stress state near the crack-tip due to bending mode. The loss of constraint is significant for high strength steels with high yield-to-tensile ratios (= yield stress/tensile strength) which have been extensively developed and widely applied to structures in recent years. ISO 27306:2016 specifies a method for converting the CTOD (crack-tip opening displacement) fracture toughness obtained from laboratory specimens to an equivalent CTOD for structural components, taking constraint loss into account. This method can also apply to fracture assessment using the stress intensity factor or the J-integral concept (see Clause 9). ISO 27306:2016 deals with the unstable fracture that occurs from a crack-like defect or fatigue crack in ferritic structural steels. Unstable fracture accompanied by a significant amount of ductile crack extension and ductile fractures are not included in the scope hereof. The CTOD fracture toughness of structural steels is measured in accordance with the established test methods, ISO 12135[1] or BS 7448-1. The fracture assessment of a cracked component is done using an established method such as FAD (Failure Assessment Diagram) in the organization concerned, and reference is not made to the details thereof in ISO 27306:2016. It can be used for eliminating the excessive conservatism frequently associated with the conventional fracture mechanics methods and accurately assessing the unstable fracture initiation limit of structural components from the fracture toughness of the structural steel. This is also used for rationally determining the fracture toughness of materials to meet the design requirements of performance of structural components.

ISO 26843:205 specifies requirements for performing and evaluating instrumented precracked Charpy impact tests on metallic materials using a fracture mechanics approach. Minimum requirements are given for measurement and recording equipment such that similar sensitivity and comparable measurements are achieved. Dynamic fracture mechanics properties determined using this International Standard are comparable with conventional large-scale fracture mechanics results when the corresponding validity criteria are met. Because of the small absolute size of the Charpy specimen, this is often not the case. Nevertheless, the values obtained can be used in research and development of materials, in quality control, and to establish the variation of properties with test temperature under impact loading rates. Fracture toughness properties determined through the use of this International Standard may differ from values measured at quasistatic loading rates. Indeed, an increase in loading rate causes a decrease in fracture toughness when tests are performed in the brittle or ductile-to-brittle regimes; the opposite is observed (i.e. increase in fracture toughness) in the fully ductile regime. More information on the dependence of fracture toughness on loading (or strain) rate is given in Reference [1]. In addition, it is generally acknowledged that fracture toughness also depends on test temperature. For these reasons, the user is required to report the actual test temperature and loading rate for each test performed. In case of cleavage fracture of ferritic steels in the ductile-to-brittle transition region, variability can be very large and cannot be adequately described by simple statistics. In this case, additional tests are required and the analysis is to be performed using a statistical procedure applicable to this type of test, see for example Reference [2]. NOTE Modifications to the analytical procedures prescribed in Reference [2] might be necessary to account for the effect of elevated (impact) loading rates.

ISO 14556:2015 specifies a method of instrumented Charpy V-notch pendulum impact testing on metallic materials and the requirements concerning the measurement and recording equipment. With respect to the Charpy pendulum impact test described in ISO 148‑1, this test provides further information on the fracture behaviour of the product under impact testing conditions. General information about instrumented impact testing can be found in Reference [1] to Reference [5].

ISO 22889:2013 specifies methods for determining the resistance to stable crack extension in terms of crack opening displacement, δ5, and critical crack tip opening angle, ψc, for homogeneous metallic materials by the quasistatic loading of cracked specimens that exhibit low constraint to plastic deformation. Compact and middle-cracked tension specimens are notched, precracked by fatigue, and tested under slowly increasing displacement. ISO 22889:2013 describes methods covering tests on specimens not satisfying requirements for size-insensitive fracture properties; namely, compact specimens and middle-cracked tension specimens in relatively thin gauges. Methods are given for determining the crack extension resistance curve (R-curve). Point values of fracture toughness for compact specimens are determined according to ISO 12135. Methods for determining point values of fracture toughness for the middle-cracked tension specimen are given. Crack extension resistance is determined using either the multiple-specimen or single-specimen method. The multiple-specimen method requires that each of several nominally identical specimens be loaded to a specified level of displacement. The extent of ductile crack extension is marked and the specimens are then broken open to allow measurement of crack extension. Single-specimen methods based on either unloading compliance or potential drop techniques can be used to measure crack extension, provided they meet specified accuracy requirements. Recommendations for single-specimen techniques are described in ISO 12135. Using either technique, the objective is to determine a sufficient number of data points to adequately describe the crack extension resistance behaviour of a material. The measurement of δ5 is relatively simple and well established. The δ5 results are expressed in terms of a resistance curve, which has been shown to be unique within specified limits of crack extension. Beyond those limits, δ5 R-curves for compact specimens show a strong specimen dependency on specimen width, whereas the δ5 R-curves for middle-cracked tension specimens show a weak dependency. CTOA is more difficult to determine experimentally. The critical CTOA is expressed in terms of a constant value achieved after a certain amount of crack extension. The CTOA concept has been shown to apply to very large amounts of crack extension and can be applied beyond the current limits of δ5 applications. Both measures of crack extension resistance are suitable for structural assessment. The δ5 concept is well established and can be applied to structural integrity problems by means of simple crack driving force formulae from existing assessment procedures. The CTOA concept is generally more accurate. Its structural application requires numerical methods, i.e. finite element analysis. Investigations have shown a very close relation between the concept of constant CTOA and a unique R-curve for both compact and middle-cracked tension specimens up to maximum load. Further study is required to establish analytical or numerical relationships between the δ5 R-curve and the critical CTOA values.

ISO 12110-1:2013 establishes general principles for fatigue testing of laboratory specimens under a sequence of cycles the amplitude of which varies from cycle to cycle. This sequence of cycles is called loading time history (see 3.7) and is usually derived from loading measurements performed on components or structures submitted to true service loadings. Detailed description of service loads recording is relevant to each laboratory or industrial sector and is therefore outside the scope of ISO 12110-1:2013. The aim of the two parts of ISO 12110 is to set requirements and give some guidance on how to perform a variable amplitude fatigue test in order to produce consistent results for comparison purposes taking into account the typical scatter of fatigue data. Achieving this should help designers to correlate models and experimental data obtained from various sources. Since ISO 12110-1:2013 involves mainly loading time histories and control signal generation, one expects it might be applied to strain or fatigue crack growth rate controlled loading conditions as well as to force-controlled loading conditions. This is theoretically true but precautions may be taken when applying this document to loading modes other than force-controlled loading mode. ISO 12110-1:2013 relates to variable amplitude loading under force control mode which corresponds to most of the variable amplitude fatigue tests performed worldwide at the date of publication. ISO 12110-1:2013 applies to the single actuator loading mode which corresponds to uniaxial loading in many cases. The variable amplitude loading time histories referred in this document are deterministic; that is why ISO 12110-1:2013 deals with variable amplitude loading instead of random loading. The following issues are not within the scope of ISO 12110-1:2013 and therefore will not be addressed: constant amplitude tests with isolated overloads or underloads; tests on large components or structures;environmental effects like corrosion, creep linked to temperature/time interactions leading to frequency and waveform effects; multiaxial loading.

ISO 12110-2:2013 presents cycle counting techniques and data reduction methods which are used in variable amplitude fatigue testing. For each test or test series, cycle counting is mandatory whereas data reduction methods are optional. ISO 12110-2:2013 supports ISO 12110-1 which contains the general principles and describes the common requirements about variable amplitude fatigue testing. ISO 12110-2:2013, the term "loading" refers either to force, stress, or strain since the methods presented here are valid for all. The following issues are not within the scope of this document and therefore are not addressed: constant amplitude tests with isolated overloads or underloads; large components or structures; environmental effects like corrosion, creep, etc. linked to temperature/time interactions leading to frequency and waveform effects; multiaxial loading.

ISO 12107:2012 presents methods for the experimental planning of fatigue testing and the statistical analysis of the resulting data. The purpose is to determine the fatigue properties of metallic materials with both a high degree of confidence and a practical number of specimens.

ISO 4965-1:2012 describes two methods for determining the relationship between the dynamic force range applied to a test-piece in a uniaxial, sinusoidal, constant amplitude test and the force range indicated by the testing system. These methods are applicable to dynamic testing systems operating away from system resonant frequencies and are relevant to testing systems where the dynamic force measurement errors are either unknown or where they are expected to exceed 1 % of the applied force range. The dynamic force measurement errors are determined by comparison of the peak forces indicated by the dynamic testing system with those measured by the strain gauged dynamic calibration device (DCD). This DCD has previously undergone static calibration against the testing system indicator. For Method A (Replica test-piece method), the dynamic calibration is applicable over the validated range of frequencies for that type of test-piece only. A frequency-dependent correction factor is applicable for the correction of dynamic force measurement errors of up to 10 % of dynamic force range. By using such a correction factor, the actual test specimen dynamic force measurement error will be reduced to less than 1 % of the dynamic force range. For Method B (Compliance envelope method), the dynamic calibration is applicable over the range of test frequencies validated for test-pieces whose compliance lies between those of the two DCDs. No correction factor is applicable, as Method B does not permit dynamic force measurement errors above 1 % of the dynamic force range.

In order to perform a dynamic calibration of a uniaxial testing system, it is necessary to measure the forces experienced by the test-piece to known levels of accuracy; this measurement is made by a dynamic calibration device (DCD) in place of the test-piece and the calibration method is described in ISO 4965-1. ISO 4965-2:2012 defines the calibration procedure for the DCD's instrumentation. The method for the analysis of the results is also described, leading to a range of testing frequencies over which the instrumentation is valid for use with DCDs in accordance with ISO 4965-1.

This International Standard describes a method for verifying the alignment in a testing machine using a straingauged measuring device. It is applicable to dynamic uniaxial tension/compression, pure torsion and combined tension/compression plus torsion fatigue testing machines for metallic materials. The methodology outlined in this International Standard is generic and can be applied to static testing machines and in non-metallic materials testing.

ISO 12111:2011 is applicable to the TMF (thermomechanical fatigue) testing of uniaxially loaded metallic specimens under strain control. Specifications allow for any constant cyclic amplitude of mechanical strain and temperature with any constant cyclic mechanical strain ratio and any constant cyclic temperature-mechanical strain phasing.

ISO 26845:2009 specifies requirements for performing and evaluating instrumented precracked Charpy impact tests on steels using a fracture mechanics approach. Minimum requirements are given for measurement and recording equipment, such that similar sensitivity and comparable measurements are achieved. ISO 26845:2009 can be applied to other metallic materials by agreement. Dynamic fracture mechanics properties determined using ISO 26845:2009 are comparable to conventional large-scale fracture mechanics results when the corresponding validity criteria are met. Because of the small absolute size of the Charpy specimen, this is often not the case. Nevertheless, the values obtained can be used in research and development of materials, in quality control and service evaluation and to establish the variation of properties with test temperature under impact loading rates.

ISO 3785:2006 specifies a method for designating test specimen axes in relation to product texture by means of an X-Y-Z orthogonal coordinate system. The system applies equally to unnotched and notched (or precracked) test specimens. The method is intended only for metallic materials with uniform texture that can be unambiguously determined.

ISO 12135:2016 specifies methods for determining fracture toughness in terms of K, δ, J and R-curves for homogeneous metallic materials subjected to quasistatic loading. Specimens are notched, precracked by fatigue and tested under slowly increasing displacement. The fracture toughness is determined for individual specimens at or after the onset of ductile crack extension or at the onset of ductile crack instability or unstable crack extension. In some cases in the testing of ferritic materials, unstable crack extension can occur by cleavage or ductile crack initiation and growth, interrupted by cleavage extension. The fracture toughness at crack arrest is not covered by this document. In cases where cracks grow in a stable manner under ductile tearing conditions, a resistance curve describing fracture toughness as a function of crack extension is measured. In most cases, statistical variability of the results is modest and reporting the average of three or more test results is acceptable. In cases of cleavage fracture of ferritic materials in the ductile-to-brittle transition region, variability can be large and additional tests may be required to quantify statistical variability. Special testing requirements and analysis procedures are necessary when testing weldments and these are described in ISO 15653 which is complementary to this document. When fracture occurs by cleavage or when cleavage is preceded by limited ductile crack extension, it may be useful to establish the reference temperature for the material by conducting testing and analysis in accordance with ASTM E1921.[2]

ISO 12108:2012 describes tests for determining the fatigue crack growth rate from the fatigue crack growth threshold stress-intensity factor range to the onset of rapid, unstable fracture. ISO 12108:2012 is primarily intended for use in evaluating isotropic metallic materials under predominantly linear-elastic stress conditions and with force applied only perpendicular to the crack plane (mode I stress condition), and with a constant stress ratio.

ISO 1352:2011 specifies the conditions for performing torsional, constant-amplitude, nominally elastic stress fatigue tests on metallic specimens without deliberately introducing stress concentrations. The tests are carried out at ambient temperature (ideally at between 10 °C and 35 °C) in air by applying a pure couple to the specimen about its longitudinal axis. While the form, preparation and testing of specimens of circular cross-section and tubular cross-section are described in ISO 1352:2011, component and other specialized types of testing are not included. Similarly, low-cycle torsional fatigue tests carried out under constant-amplitude angular displacement control, which lead to failure in a few thousand cycles, are also excluded.

ISO 12737:2010 specifies the ISO method for determining the plane-strain fracture toughness of homogeneous metallic materials using a specimen that is notched and precracked by fatigue, and subjected to slowly increasing crack displacement force.

ISO 1143:2010 specifies the method for rotating bar bending fatigue testing of metallic materials. The tests are conducted at room temperature or elevated temperature in air, the specimen being rotated.

ISO 15653:2010 specifies methods for determining fracture toughness in terms of K (stress intensity factor), δ (crack tip opening displacement, CTOD) and J (experimental equivalent of the J‑integral) for welds in metallic materials. ISO 15653 is complementary to ISO 12135, which covers all aspects of fracture toughness testing of parent metal and which needs to be used in conjunction with this document. It describes methods for determining point values of fracture toughness. It should not be considered a way of obtaining a valid R‑curve (resistance-to-crack-extension curve). However, the specimen preparation methods described in ISO 15653 could be usefully employed when determining R‑curves for welds. The methods use fatigue precracked specimens which have been notched, after welding, in a specific target area in the weld. Methods are described to evaluate the suitability of a weld for notch placement within the target area, which is either within the weld metal or within the weld heat-affected zone (HAZ), and then, where appropriate, to evaluate the effectiveness of the fatigue crack in sampling these areas.

ISO 148-1:2009 specifies the Charpy pendulum impact (V‑notch and U‑notch) test method for determining the energy absorbed in an impact test of metallic materials. ISO 148-1:2009 does not apply to instrumented impact testing, which is specified in ISO 14556.

ISO 27306:2009 specifies a method for converting the CTOD (Crack-Tip Opening Displacement) fracture toughness obtained from laboratory specimens to an equivalent CTOD for structural components, taking constraint loss into account. This method can also apply to fracture toughness assessment using the stress intensity factor or the J-integral concept. ISO 27306:2009 deals with the unstable fracture that occurs from a crack-like defect or fatigue crack in ferritic structural steels. Unstable fracture accompanied by a significant amount of ductile crack extension and ductile fractures is not included in the scope hereof. ISO 27306:2009 can be used for eliminating the excessive conservatism frequently associated with the conventional fracture mechanics methods and accurately assessing the unstable fracture initiation limit of structural components from the fracture toughness of the structural steel. This is also used for rationally determining the fracture toughness of materials to meet the design requirements of deformability of structural components.

ISO 148-3:2008 covers the requirements, preparation and methods for qualifying test pieces used for the indirect verification of pendulum impact testing machines in accordance with ISO 148-2. ISO 148-3:2008 specifies notched test pieces with nominal dimensions identical to those specified in ISO 148-1; however, the tolerances are more stringent.

ISO 148-2:2008 covers the verification of the constructional elements of pendulum-type impact testing machines. It is applicable to machines with 2 mm or 8 mm strikers used for pendulum impact tests carried out, for instance, in accordance with ISO 148-1. It can analogously be applied to pendulum impact testing machines of various capacities and of different design. Impact machines used for industrial, general or research laboratory testing of metallic materials in accordance with ISO 148-2:2008 are referred to as industrial machines. Those with more stringent requirements are referred to as reference machines. Specifications for the verification of reference machines are found in ISO 148-3. ISO 148-2:2008 describes two methods of verification: a direct method and an indirect method.

ISO 22889:2007 specifies methods for determining the resistance to stable crack extension in terms of crack opening displacement and critical crack tip opening angle for homogeneous metallic materials by the quasistatic loading of cracked specimens that exhibit low constraint to plastic deformation. Compact and middle-cracked tension specimens are notched, precracked by fatigue, and tested under slowly increasing displacement. ISO 22889:2007 describes methods covering tests on specimens not satisfying requirements for size-insensitive fracture properties; namely, compact specimens and middle-cracked tension specimens in relatively thin gauges. Methods are given for determining the crack extension resistance curve. Methods for determining point values of fracture toughness for the middle-cracked tension specimen are also given.

ISO 148-1:2006 specifies the Charpy pendulum impact (V-notch and U-notch) test method for determining the energy absorbed in an impact test of metallic materials. ISO 148-1:2006 does not address instrumented impact testing, which is specified in ISO 14556:2000.

ISO 12737:2005 specifies the ISO method for determining the plane-strain fracture toughness of homogeneous metallic materials using a specimen that is notched and precracked by fatigue, and subjected to a slowly increasing crack displacement force.

International Standard ISO 12135 specifies methods for determining fracture toughness in terms of K, δ, J and R-curves for homogeneous metallic materials subjected to quasistatic loading. Specimens are notched, precracked by fatigue and tested under slowly increasing displacement.

Method for determining the plan-strain fracture toughness of homogeneous metallic materials using a specimen that is notched and precracked by fatigue.

Specifies the charpy impact method using V-notch test pieces. Determines the impact strength of steel by breaking by one blow from a swinging pendulum, under conditions defined hereafter, a test piece resting on two supports and determining the energy absorbed.

Specifies a method for the identification of test piece axes in relation to the grain flow, by means of a system of co-ordinates. Applies to both unnotched metal test pieces. The system present is only intended to be applied in situations where a uniform grain flow can be unambiguously indentified (see also 4.2 and the annex).

Specifies the charpy impact method using U-notch test pieces. Determines the impact strength of steel by breaking by one blow from a swinging pendulum, under conditions defined hereafter, a test piece resting on two supports and determining the energy absorbed.