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This guide covers the definition and rating of the microstructure of carbide structures in annealed high carbon bearing steels. Requirements for the optical metallograph apparatus and specimen preparation including polishing and etching are detailed. The description of the reference photomicrographs (graded illustrations of annealed carbides categorized by size, network, and lamellar content (shape)) that shall be used in the evaluation and the equation that shall define the rating are given.1.1 This guide covers the description of carbide structures in annealed high carbon bearing steels.1.2 Included is a guide for rating steel specimens by a graded series of photomicrographs showing the incidence of certain conditions.1.3 The reference photomicrographs are graded illustrations of annealed carbides categorized by size, network, and lamellar content (shape).1.4 This guide is to facilitate communication and description of microstructure. It does not establish limits of acceptability. Such limits are a matter of agreement between user and producer.1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.6 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.1.7 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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5.1 This test method is suitable for manufacturing control and for verifying that a product meets specifications. This test method provides rapid, multi-element determinations with sufficient accuracy to ensure product quality and to minimize production delays. The analytical performance data may be used as a benchmark to determine if similar X-ray spectrometers provide equivalent precision and accuracy, or if the performance of a particular X-ray spectrometer has changed.5.2 Calcium is sometimes added to steel to affect inclusion shape which enhances certain mechanical properties of steel. This test method is useful for determining the residual calcium in the steel after such treatment.5.2.1 Because calcium occurs primarily in inclusions, the precision of this test method is a function of the distribution of the calcium-bearing inclusions in the steel. The variation of determinations on freshly prepared surfaces will give some indication of the distribution of these inclusions.1.1 This test method covers the wavelength dispersive X-ray fluorescence analysis of low-alloy steels for the following elements:Element Mass FractionRange, %Calcium 0.001 to 0.007Chromium 0.04 to 2.5Cobalt 0.03 to 0.2Copper 0.03 to 0.6Manganese 0.04 to 2.5Molybdenum 0.005 to 1.5Nickel 0.04 to 3.0Niobium 0.002 to 0.1Phosphorus 0.010 to 0.08Silicon 0.06 to 1.5Sulfur 0.009 to 0.1Vanadium 0.012 to 0.61.1.1 Unless exceptions are noted, mass fraction ranges can be extended and additional elements can be included by the use of suitable reference materials and measurement conditions. Deviations from the published scope must be validated by experimental means. See Guide E2857 for information on validation options.1.2 The values stated in the International System of Units (SI) are to be regarded as standard. The values given in parentheses are mathematical conversions to other units that are provided for information only, because they may be used in older software and laboratory procedures.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. Specific precautionary statements are given in Section 10.1.4 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.

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4.1 A pressure vessel surveillance program requires a methodology for relating radiation-induced changes in materials exposed in accelerated surveillance locations to the condition of the pressure vessel (see Practice E853). An important consideration is that the irradiation exposures be expressed in a unit that is physically related to the damage mechanisms.4.2 A major source of neutron radiation damage in metals is the displacement of atoms from their normal lattice sites. Hence, an appropriate damage exposure index is the number of times, on the average, that an atom has been displaced during an irradiation. This can be expressed as the total number of displaced atoms per unit volume, per unit mass, or per atom of the material. Displacements per atom is the most common way of expressing this quantity. The number of dpa associated with a particular irradiation depends on the amount of energy deposited in the material by the neutrons, and hence, depends on the neutron spectrum. (For a more extended discussion, see Practice E521.)4.3 No simple correspondence exists in general between dpa and a particular change in a material property. A reasonable starting point, however, for relative correlations of property changes produced in different neutron spectra is the dpa value associated with each environment. That is, the dpa values themselves provide a spectrum-sensitive index that may be a useful correlation parameter, or some function of the dpa values may affect correlation.4.4 Since dpa is a construct that depends on a model of the neutron interaction processes in the material lattice, as well as the cross section (probability) for each of these processes, the value of dpa would be different if improved models or cross sections are used. The calculated displacement cross section for ferritic iron, as given in this practice, is determined by the procedure given in 6.3. The currently recommended iron displacement cross section in this practice (Table 1) was generated using the ENDF/B-VI iron cross section (1).3 A recent calculation using ENDF/B-VII.0 produced identical results (2, 3). The iron cross section data in ENDF/B-VII.1 does not differ from ENDF/B-VII.0. Although the ENDF/B-VI based iron displacement cross section differs from the previously recommended ENDF/B-IV iron displacement cross section (1) by about 60 % in the energy region around 10 keV, by about 10 % for energies between 100 keV and 2 MeV, and by a factor of 4 near 1 keV due to the opening of reaction channels in the cross section, the integral iron dpa values are much less sensitive to the change in cross sections. The update from ENDF/B-IV to ENDF/B-VI dpa rates, when applied to the H. B. Robinson-2 pressurized water reactor, resulted in “up to ∼4 % higher dpa rates in the region close to the pressure vessel outer surface” and in “slightly lower dpa rates ... close to the pressure vessel inner wall” (4, 5). Table 2 presents a comparison of a previous edition (Practice E693–94) and currently recommended dpa estimates for several neutron spectra.(A) Energies represent the lower bin boundary. The upper bin limit is 20.0 MeV.(A) The spectrum-average dpa values in this table were computed using Eq 11 in a 640 SAND-II energy group representation and a lower integration bound of Eo = 10–10 MeV.1.1 This practice describes a standard procedure for characterizing neutron irradiations of iron (and low alloy steels) in terms of the exposure index displacements per atom (dpa) for iron.1.2 Although the methods of this practice apply to any material for which a displacement cross section σd(E) is known (see Practice E521), this practice is written specifically for iron.1.3 It is assumed that the displacement cross section for iron is an adequate approximation for calculating displacements in steels that are mostly iron (95 to 100 %) in radiation fields for which secondary damage processes are not important.1.4 Procedures analogous to this one can be formulated for calculating dpa in charged particle irradiations. (See Practice E521.)1.5 The application of this practice requires knowledge of the total neutron fluence and flux spectrum. Refer to Practice E521 for determining these quantities.1.6 The correlation of radiation effects data is beyond the scope of this practice.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 Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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6.1 Use of the etch test allows rapid acceptance of specific lots of material without the need to perform time-consuming and costly hot acid immersion tests on those lots.AbstractThis specification covers the standard practices for detecting susceptibility to intergranular attack in austenitic stainless steels. These practices include five intergranular corrosion tests, namely: (1) oxalic acid etch test for classification of etch structures of austenitic stainless steels; (2) ferric sulfate-sulfuric acid test, (3) nitric acid test and (4) copper-copper sulfate-sulfuric acid test for detecting susceptibility to intergranular attack in austenitic stainless steels; and (5) copper-copper sulfate-50% sulfuric acid test for detecting susceptibility to intergranular attack in molybdenum-bearing cast austenitic stainless steels. Methods for preparing the test specimens, rapid screening tests, apparatus setup and testing procedures, and calculations and report contents are described for each testing practice. The etch structure types used to classify the specimens are: step structure, dual structure, ditch structure, isolated ferrite, interdendritic ditches, end-grain pitting I, and end-grain pitting II.1.1 These practices cover the following five tests:1.1.1 Practice A—Oxalic Acid Etch Test for Classification of Etch Structures of Austenitic Stainless Steels (Sections 4 to 13, inclusive),1.1.2 Practice B—Ferric Sulfate-Sulfuric Acid Test for Detecting Susceptibility to Intergranular Attack in Austenitic Stainless Steels (Sections 14 to 25, inclusive),1.1.3 Practice C—Nitric Acid Test for Detecting Susceptibility to Intergranular Attack in Austenitic Stainless Steels (Sections 26 to 36, inclusive),1.1.4 Practice E—Copper–Copper Sulfate–Sulfuric Acid Test for Detecting Susceptibility to Intergranular Attack in Austenitic Stainless Steels (Sections 37 to 46, inclusive), and1.1.5 Practice F—Copper–Copper Sulfate–50 % Sulfuric Acid Test for Detecting Susceptibility to Intergranular Attack in Molybdenum-Bearing Austenitic Stainless Steels (Sections 47 to 58, inclusive).1.2 The Oxalic Acid Etch Test is a rapid method of identifying, by simple etching, those specimens of certain stainless steel grades that are essentially free of susceptibility to intergranular attack associated with chromium carbide precipitates. These specimens will have low corrosion rates in certain corrosion tests and therefore can be eliminated (screened) from testing as “acceptable.” The etch test is applicable only to those grades listed in the individual hot acid tests and classifies the specimens either as “acceptable” or as “suspect.”1.3 The ferric sulfate-sulfuric acid test, the copper–copper sulfate–50 % sulfuric acid test, and the nitric acid test are based on weight loss determinations and, thus, provide a quantitative measure of the relative performance of specimens evaluated. In contrast, the copper–copper sulfate–16 % sulfuric acid test is based on visual examination of bend specimens and, therefore, classifies the specimens only as acceptable or nonacceptable.1.4 The presence or absence of intergranular attack in these tests is not necessarily a measure of the performance of the material in other corrosive environments. These tests do not provide a basis for predicting resistance to forms of corrosion other than intergranular, such as general corrosion, pitting, or stress-corrosion cracking.NOTE 1: See Appendix X1 for information regarding test selection.1.5 The values stated in SI units are to be regarded as standard. The inch-pound equivalents are in parentheses and may be approximate.1.6 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. Some specific hazards statements are given in 10.1, 20.1.1, 20.1.9, 31.3, 34.4, 53.1.1, and 53.1.10.1.7 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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This specification covers the chemical requirements for wrought stainless steels used for the manufacture of surgical instruments. Classes of stainless steels covered here are Class 3 (austenitic stainless steel), Class 4 (martensitic stainless steel), Class 5 (precipitation hardening stainless steel), and Class 6 (ferritic stainless steel). The data contained in this specification, such as typical hardness values, common heat treating cycles, and examples of selected stainless steels that have been used for surgical instruments, are provided for reference only. Mechanical property, heat treatment, hardness, and all other requirements except for chemical composition, are governed by the appropriate material standards as specified or as agreed upon between purchaser and supplier. 1.1 This specification covers the chemistry requirements for wrought stainless steels used for the manufacture of surgical instruments. The data contained in Tables 1-4 of this specification, including typical hardness values, common heat treating cycles, and examples of selected stainless steels that have been used for surgical instruments, is provided for reference only. Mechanical property requirements, heat treating requirements, hardness requirements, and all other requirements except chemistry are governed by the appropriate material standards as referenced below or as agreed upon between the purchaser and supplier. 1.2 The SI units in this standard are the primary units. The values stated in either primary SI units or secondary inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of each other. Combining values from the two systems may result in nonconformance with the standard. 1.3 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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4.1 These test methods for the chemical analysis of metals and alloys are primarily intended as referee methods to test such materials for compliance with compositional specifications particularly those under the jurisdiction of ASTM Committee A01 on Steel, Stainless Steel, and Related Alloys. It is assumed that all who use these test methods will be trained analysts capable of performing common laboratory procedures skillfully and safely. It is expected that work will be performed in a properly equipped laboratory under appropriate quality control practices such as those described in Guide E882.1.1 These test methods cover the chemical analysis of tool steels and other similar medium- and high-alloy steels having chemical compositions within the following limits:Element Composition Range, %Aluminum   0.005 to 1.5Boron   0.001 to 0.10Carbon   0.03  to 2.50Chromium   0.10  to 14.0Cobalt   0.10  to 14.0Copper   0.01  to 2.0Lead   0.001 to 0.01Manganese   0.10  to 15.00Molybdenum   0.01  to 10.00Nickel   0.02  to 4.00Nitrogen   0.001 to 0.20Phosphorus   0.002 to 0.05Silicon   0.10  to 2.50Sulfur   0.002 to 0.40Tungsten   0.01  to 21.00Vanadium   0.02  to 5.501.2 The test methods in this standard are contained in the sections indicated below:    SectionsCarbon, Total, by the Combustion— Thermal Conductivity Method— Discontinued 1986   125–135Carbon, Total, by the Combustion Gravimetric Method—Discontinued 2012   78–88Chromium by the Atomic Absorption Spectrometry Method (0.006 % to 1.00 %) 174–183Chromium by the Peroxydisulfate Oxidation—Titration Method   (0.10 % to 14.00 %) 184–192Chromium by the Peroxydisulfate-Oxidation Titrimetric Method—Discontinued 1980   117–124Cobalt by the Ion-Exchange— Potentiometric Titration Method     (2 % to 14 %)  52–59Cobalt by the Nitroso-R-Salt  Spectrophotometric Method  (0.10 % to 5.0 %)  60–69Copper by the Neocuproine  Spectrophotometric Method  (0.01 % to 2.00 %) 89–98Copper by the Sulfide Precipitation- Electrodeposition Gravimetric Method   (0.01 % to 2.0 %)  70–77Lead by the Ion-Exchange—Atomic  Absorption Spectrometry Method (0.001 % to 0.01 %) 99–108Manganese by the Periodate  Spectrophotometric Method  (0.10 % to 5.00 %) 9–18Molybdenum by the Ion Exchange– 8-Hydroxyquinoline Gravimetric Method    203–210Molybdenum by the Thiocyanate Spectrophotometric Method  (0.01 % to 1.50 %) 162–173Nickel by the Dimethylglyoxime Gravimetric Method (0.1 % to 4.0 %) 144–151Phosphorus by the Alkalimetric Method  (0.01 % to 0.05 %) 136–143Phosphorus by the Molybdenum Blue  Spectrophotometric Method (0.002 % to 0.05 %) 19–29Silicon by the Gravimetric Method  (0.10 % to 2.50 %) 45–51Sulfur by the Gravimetric Method—Discontinued 1988   29–35Sulfur by the Combustion-Iodate  Titration Method—Discontinued 2012   36–44Sulfur by the Chromatographic Gravimetric Method—Discontinued 1980   109–116Tin by the Solvent Extraction— Atomic Absorption Spectrometry Method (0.002 % to 0.10 %) 152–161Vanadium by the Atomic Absorption Spectrometry Method (0.006 % to 0.15 %) 193–2021.3 Test methods for the determination of carbon and sulfur not included in this standard can be found in Test Methods E1019.1.4 Some of the composition ranges given in 1.1 are too broad to be covered by a single test method and therefore this standard contains multiple test methods for some elements. The user must select the proper test method by matching the information given in the and Interference sections of each test method with the composition of the alloy to be analyzed.1.5 The values stated in SI units are to be regarded as standard.1.6 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. Specific hazards statements are given in Section 6 and in special “Warning” paragraphs throughout these test methods.1.7 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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AbstractThese test methods cover the detection of detrimental intermetallic phase in duplex austenitic/ferritic stainless steel to the extent that toughness and corrosion resistance is affected significantly. These test methods will not necessarily detect losses of toughness or corrosion resistance attributable to other causes. Test method A-sodium hydroxide etch test, test method B-Charpy impact test, and test method C-ferric chloride corrosion test shall be made for classification of structures of duplex stainless steels.1.1 The purpose of these test methods is to allow detection of the presence of intermetallic phases in certain duplex stainless steels as listed in Table 1, Table 2, and Table 3 to the extent that toughness or corrosion resistance is affected significantly. These test methods will not necessarily detect losses of toughness or corrosion resistance attributable to other causes. Similar test methods for other duplex stainless steels are described in Test Method A1084, but the procedures described in this standard differ significantly from Test Methods A, B, and C in A1084.1.2 Duplex (austenitic-ferritic) stainless steels are susceptible to the formation of intermetallic compounds during exposures in the temperature range from approximately 600 to 1750 °F (320 to 955 °C). The speed of these precipitation reactions is a function of composition and thermal or thermomechanical history of each individual piece. The presence of these phases is detrimental to toughness and corrosion resistance.1.3 Correct heat treatment of duplex stainless steels can eliminate these detrimental phases. Rapid cooling of the product provides the maximum resistance to formation of detrimental phases by subsequent thermal exposures.1.4 Compliance with the chemical and mechanical requirements for the applicable product specification does not necessarily indicate the absence of detrimental phases in the product.1.5 These test methods include the following:1.5.1 Test Method A—Sodium Hydroxide Etch Test for Classification of Etch Structures of Duplex Stainless Steels (Sections 3 – 7).1.5.2 Test Method B—Charpy Impact Test for Classification of Structures of Duplex Stainless Steels (Sections 8 – 13).1.5.3 Test Method C—Ferric Chloride Corrosion Test for Classification of Structures of Duplex Stainless Steels (Sections 14 – 20).1.6 The presence of detrimental intermetallic phases is readily detected in all three tests, provided that a sample of appropriate location and orientation is selected. Because the occurrence of intermetallic phases is a function of temperature and cooling rate, it is essential that the tests be applied to the region of the material experiencing the conditions most likely to promote the formation of an intermetallic phase. In the case of common heat treatment, this region will be that which cooled most slowly. Except for rapidly cooled material, it may be necessary to sample from a location determined to be the most slowly cooled for the material piece to be characterized.1.7 The tests do not determine the precise nature of the detrimental phase but rather the presence or absence of an intermetallic phase to the extent that it is detrimental to the toughness and corrosion resistance of the material.1.8 Examples of the correlation of thermal exposures, the occurrence of intermetallic phases, and the degradation of toughness and corrosion resistance are given in Appendix X1 and Appendix X2.1.9 The values stated in either inch-pound or SI units are to be regarded as the standard. The values given in parentheses are for information only.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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This specification covers specially heat treated 5% and 5 1/2% nickel alloy steel plates intended primarily for welded pressure vessels for service at low or cryogenic temperatures. Plates are classified as Grade A and Grade B. The steel shall be killed and shall conform to the fine austenitic grain size requirements specified. Plates shall be heat treated in accordance with the required specifications. The steel shall conform to the chemical requirements specified. Tensions tests and impacts tests shall be made to meet the mechanical requirements specified.1.1 This specification2 covers specially heat treated 5 % and 5 1/2 % nickel alloy steel plates intended primarily for welded pressure vessels for service at low or cryogenic temperatures.1.2 The maximum thickness of plates which can be supplied under this specification is limited only by the capacity of the material to meet the specified requirements.1.3 This material is susceptible to magnetization. Use of magnets in handling after heat treatment should be avoided if residual magnetism would be detrimental to subsequent fabrication or service.1.4 The values stated in either inch-pound units or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system are not exact equivalents; therefore, each system must be used independently of the other. Combining values from the two systems may result in nonconformance with the specification.1.5 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.1.6 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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AS 1330-1974 Method for the dropweight tear test of ferritic steels 现行 发布日期 :  1970-01-01 实施日期 : 

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5.1 This test method covers a procedure for experimentally determining macroscopic residual stress tensor components of quasi-isotropic bearing steel materials by XRD. Here the stress components are represented by the tensor σij as shown in Eq 1 (1,5 p. 40). The stress strain relationship in any direction of a component is defined by Eq 2 with respect to the azimuth phi(φ) and polar angle psi(ψ) defined in Fig. 1 (1, p. 132). 5.1.1 Alternatively, Eq 2 may also be shown in the following arrangement (2, p. 126): 5.2 Using XRD and Bragg’s law, interplanar strain measurements are performed for multiple orientations. The orientations are selected based on a modified version of Eq 2, which is dictated by the mode used. Conflicting nomenclature may be found in literature with regard to mode names. For example, what may be referred to as a ψ (psi) diffractometer in Europe may be called a χ (chi) diffractometer in North America. The three modes considered here will be referred to as omega, chi, and modified-chi as described in 9.5. 5.3 Omega Mode (Iso Inclination) and Chi Mode (Side Inclination)—Interplanar strain measurements are performed at multiple ψ angles along one φ azimuth (let φ = 0°) (Figs. 2 and 3), reducing Eq 2 to Eq 3. Stress normal to the surface (σ33) is assumed to be insignificant because of the shallow depth of penetration of X-rays at the free surface, reducing Eq 3 to Eq 4. Post-measurement corrections may be applied to account for possible σ33 influences (12.12). Since the σij values will remain constant for a given azimuth, the s1{hkl} term is renamed C. FIG. 2 Omega Mode Diagram for Measurement in σ11 Direction FIG. 3 Chi Mode Diagram for Measurement in σ11 Direction Note 1: Stress matrix is rotated 90° about the surface normal compared to Fig. 2 and Fig. 14. 5.3.1 The measured interplanar spacing values are converted to strain using Eq 24, Eq 25, or Eq 26. Eq 4 is used to fit the strain versus sin2ψ data yielding the values σ11, τ13, and C. The measurement can then be repeated for multiple phi angles (for example 0, 45, and 90°) to determine the full stress/strain tensor. The value, σ11, will influence the overall slope of the data, while τ13 is related to the direction and degree of elliptical opening. Fig. 4 shows a simulated d versus sin2ψ profile for the tensor shown. Here the positive 20-MPa τ13 stress results in an elliptical opening in which the positive psi range opens upward and the negative psi range opens downward. A higher τ13 value will cause a larger elliptical opening. A negative 20-MPa τ13 stress would result in the same elliptical opening only the direction would be reversed with the positive psi range opening downwards and the negative psi range opening upwards as shown in Fig. 5. FIG. 4 Sample d (2θ) Versus sin2ψ Dataset with σ11 = -500 MPa and τ13 = +20 MPa FIG. 5 Sample d (2θ) Versus sin2ψ Dataset with σ11 = -500 MPa and τ13 = -20 MPa 5.4 Modified Chi Mode—Interplanar strain measurements are performed at multiple β angles with a fixed χ offset, χm (Fig. 6). Measurements at various β angles do not provide a constant φ angle (Fig. 7), therefore, Eq 2 cannot be simplified in the same manner as for omega and chi mode. FIG. 6 Modified Chi Mode Diagram for Measurement in σ11 Direction FIG. 7 ψ and φ Angles Versus β Angle for Modified Chi Mode with χm = 12° 5.4.1 Eq 2 shall be rewritten in terms of β and χm. Eq 5 and 6 are obtained from the solution for a right-angled spherical triangle (3). 5.4.2 Substituting φ and ψ in Eq 2 with Eq 5 and 6 (see X1.1), we get: 5.4.3 Stress normal to the surface (σ33) is assumed to be insignificant because of the shallow depth of penetration of X-rays at the free surface reducing Eq 7 to Eq 8. Post-measurement corrections may be applied to account for possible σ33 influences (see 12.12). Since the σij values and χm will remain constant for a given azimuth, the s1{hkl} term is renamed C, and the σ22 term is renamed D. 5.4.4 The σ11 influence on the d versus sin2β plot is similar to omega and chi mode (Fig. 8) with the exception that the slope shall be divided by cos2χm. This increases the effective 1/2 s2{hkl} by a factor of 1/cos2χm for σ11. FIG. 8 Sample d (2θ) Versus sin2β Dataset with σ11 = -500 MPa 5.4.5 The τij influences on the d versus sin2β plot are more complex and are often assumed to be zero (3). However, this may not be true and significant errors in the calculated stress may result. Figs. 9-13 show the d versus sin2β influences of individual shear components for modified chi mode considering two detector positions (χm = +12° and χm = -12°). Components τ12 and τ13 cause a symmetrical opening about the σ11 slope influence for either detector position (Figs. 9-11); therefore, σ11 can still be determined by simply averaging the positive and negative β data. Fitting the opening to the τ12 and τ13 terms may be possible, although distinguishing between the two influences through regression is not normally possible. FIG. 9 Sample d (2θ) versus sin2β Dataset with χm = +12°, σ11 = -500 MPa, and τ12 = -100 MPa FIG. 10 Sample d (2θ) Versus sin2β Dataset with χm = -12°, σ11 = -500 MPa, and τ12 = -100 MPa FIG. 11 Sample d (2θ) Versus sin2β Dataset with χm = +12 or -12°, σ11 = -500 MPa, and τ13 = -100 MPa FIG. 12 Sample d (2θ) Versus sin2β Dataset with χm = +12°, σ11 = -500 MPa, τ23 = -100 MPa, and Measured σ11 = -472.5 MPa FIG. 13 Sample d (2θ) Versus sin2β Dataset with χm = -12°, σ11 = -500 MPa, τ23 = -100 MPa, and Measured σ11 = -527.5 MPa 5.4.6 The τ23 value affects the d versus sin2β slope in a similar fashion to σ11 for each detector position (Figs. 12 and 13). This is an unwanted effect since the σ11 and τ23 influence cannot be resolved for one χm position. In this instance, the τ23 shear stress of -100 MPa results in a calculated σ11 value of -472.5 MPa for χm = +12° or -527.5 MPa for χm = -12°, while the actual value is -500 MPa. The value, σ11 can still be determined by averaging the β data for both χm positions. 5.4.7 The use of the modified chi mode may be used to determine σ11 but shall be approached with caution using one χm position because of the possible presence of a τ23 stress. The combination of multiple shear stresses including τ23 results in increasingly complex shear influences. Chi and omega mode are preferred over modified chi for these reasons. 1.1 This test method covers a procedure for experimentally determining macroscopic residual stress tensor components of quasi-isotropic bearing steel materials by X-ray diffraction (XRD). 1.2 This test method provides a guide for experimentally determining stress values, which play a significant role in bearing life. 1.3 Examples of how tensor values are used are: 1.3.1 Detection of grinding type and abusive grinding; 1.3.2 Determination of tool wear in turning operations; 1.3.3 Monitoring of carburizing and nitriding residual stress effects; 1.3.4 Monitoring effects of surface treatments such as sand blasting, shot peening, and honing; 1.3.5 Tracking of component life and rolling contact fatigue effects; 1.3.6 Failure analysis; 1.3.7 Relaxation of residual stress; and 1.3.8 Other residual-stress-related issues that potentially affect bearings. 1.4 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.5 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. 1.6 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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