1、Designation: A751 11Standard Test Methods, Practices, and Terminology forChemical Analysis of Steel Products1This standard is issued under the fixed designation A751; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last
2、 revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.INTRODUCTIONThese test methods, practices, and termin
3、ology were prepared to answer the need for a singledocument that would include all aspects of obtaining and reporting the chemical analysis of steel,stainless steel, and related alloys. Such subjects as definitions of terms and product (check) analysisvariations (tolerances) required clarification.
4、Requirements for sampling, meeting specified limits, andtreatment of data usually were not clearly established in product specifications.It is intended that these test methods, practices, and terminology will contain all requirements forthe determination of chemical composition of steel, stainless s
5、teel, or related alloys so that productspecifications will need contain only special modifications and exceptions.1. Scope*1.1 These test methods, practices, and terminology coverdefinitions, reference methods, practices, and guides relating tothe chemical analysis of steel, stainless steel, and rel
6、atedalloys. It includes both wet chemical and instrumental tech-niques.1.2 Directions are provided for handling chemical require-ments, product analyses, residual elements, and referencestandards, and for the treatment and reporting of chemicalanalysis data.1.3 These test methods, practices, and ter
7、minology applyonly to those product standards which include these testmethods, practices, and terminology, or parts thereof, as arequirement.1.4 In cases of conflict, the product specification require-ments shall take precedence over the requirements of these testmethods, practices, and terminology.
8、1.5 Attention is directed to ISO/IEC 17025 when there maybe a need for information on criteria for evaluation of testinglaboratories.1.6 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to estab
9、lish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E29 Practice for Using Significant Digits in Test Data toDetermine Conformance with SpecificationsE30 Test Methods for Chemical Analysis of
10、 Steel, CastIron, Open-Hearth Iron, and Wrought Iron3E50 Practices for Apparatus, Reagents, and Safety Consid-erations for Chemical Analysis of Metals, Ores, andRelated MaterialsE60 Practice for Analysis of Metals, Ores, and RelatedMaterials by SpectrophotometryE212 Test Method for Spectrographic An
11、alysis of Carbonand Low-Alloy Steel by the Rod-To-Rod Technique3E293 Test Method for Spectrographic Determination ofAcid-Soluble Aluminum in Low-Alloy Steel by the Solu-tion Technique3E322 Test Method for X-Ray Emission SpectrometricAnalysis of Low-Alloy Steels and Cast IronsE327 Test Method for Opt
12、ical Emission SpectrometricAnalysis of Stainless Type 18-8 Steels by the Point-To-Plane Technique3E350 Test Methods for Chemical Analysis of Carbon Steel,Low-Alloy Steel, Silicon Electrical Steel, Ingot Iron, andWrought IronE352 Test Methods for Chemical Analysis of Tool Steelsand Other Similar Medi
13、um- and High-Alloy Steels1These test methods, practices, and terminology are under the jurisdiction ofASTM Committee A01 on Steel, Stainless Steel and Related Alloys and are thedirect responsibility of Subcommittee A01.13 on Mechanical and Chemical Testingand Processing Methods of Steel Products and
14、 Processes.Current edition approved Nov. 1, 2011. Published November 2011. Originallyapproved in 1977. Last previous edition approved in 2007 as A751 08. DOI:10.1520/A0751-11.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For
15、 Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn. The last approved version of this historical standard is referencedon www.astm.org.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM Internati
16、onal, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.E353 Test Methods for Chemical Analysis of Stainless,Heat-Resisting, Maraging, and Other Similar Chromium-Nickel-Iron AlloysE354 Test Methods for Chemical Analysis of High-Temperature, Electrical, Magnetic, and
17、 Other Similar Iron,Nickel, and Cobalt AlloysE404 Test Method for Spectrographic Determination ofBoron In Carbon and LowAlloy Steel by the Point-To-Plane Technique3E415 Test Method for Atomic Emission Vacuum Spectro-metric Analysis of Carbon and Low-Alloy SteelE421 Test Method for Spectrographic Det
18、ermination ofSilicon and Aluminum in High-Purity Iron3E485 Test Method for Optical Emission Vacuum Spectro-metricAnalysis of Blast Furnace Iron by the Point-to-PlaneTechnique3E548 Guide for General Criteria Used for Evaluating Labo-ratory Competence3E572 Test Method forAnalysis of Stainless andAlloy
19、 Steelsby X-ray Fluorescence SpectrometryE663 Practice for Flame Atomic Absorption Analysis3E743 Guide for Spectrochemical Laboratory Quality Assur-ance3E851 Practice for Evaluation of Spectrochemical laborato-ries3E882 Guide for Accountability and Quality Control in theChemical Analysis LaboratoryE
20、1019 Test Methods for Determination of Carbon, Sulfur,Nitrogen, and Oxygen in Steel, Iron, Nickel, and CobaltAlloys by Various Combustion and Fusion TechniquesE1024 Guide for Chemical Analysis of Metals and MetalBearing Ores by Flame Atomic Absorption Spectropho-tometry3E1063 Test Method for X-Ray E
21、mission SpectrometricDetermination of Cerium and Lanthanum in Carbon andLow-Alloy Steel3E1085 Test Method for Analysis of Low-Alloy Steels byX-Ray Fluorescence SpectrometryE1086 Test Method for Atomic Emission Vacuum Spectro-metric Analysis of Stainless Steel by Point-to-Plane Exci-tation TechniqueE
22、1097 Guide for Direct Current Plasma-Atomic EmissionSpectrometry AnalysisE1184 Practice for Determination of Elements by GraphiteFurnace Atomic Absorption SpectrometryE1282 Guide for Specifying the Chemical Compositionsand Selecting Sampling Practices and Quantitative Analy-sis Methods for Metals, O
23、res, and Related MaterialsE1329 Practice for Verification and Use of Control Charts inSpectrochemical AnalysisE1806 Practice for Sampling Steel and Iron for Determina-tion of Chemical Composition2.2 ISO Standards:4ISO/IEC 17025 General Requirements for the Competenceof Testing and Calibration Labora
24、tories3. Terminology3.1 Definitions:3.1.1 Pertaining to Analyses:3.1.1.1 cast or heat (formerly ladle) analysisapplies tochemical analyses representative of a heat of steel as reportedto the purchaser and determined by analyzing a test sample,preferably obtained during the pouring of the steel, for
25、theelements designated in a specification.3.1.1.2 product, check or verification analysisa chemicalanalysis of the semifinished or finished product, usually for thepurpose of determining conformance to the specification re-quirements. The range of the specified composition applicableto product analy
26、sis is normally greater than that applicable toheat analysis in order to take into account deviations associatedwith analytical reproducibility (Note 1) and the heterogeneityof the steel.NOTE 1All of the chemical analysis procedures referenced in thisdocument include precision statements with reprod
27、ucibility data with theexception of Test Methods E50.3.1.1.3 product analysis tolerances (Note 2)a permissiblevariation over the maximum limit or under the minimum limitof a specified element and applicable only to product analyses,not cast or heat analyses.NOTE 2The term “analysis tolerance” is oft
28、en misunderstood. It doesnot apply to cast or heat analyses determined to show conformance tospecified chemical limits. It applies only to product analysis and becomesmeaningful only when the heat analysis of an element falls close to one ofthe specified limits. For example, stainless steel UNS 3040
29、0 limits forchromium are 18.00 to 20.00 %. A heat that the producer reported as18.01 % chromium may be found to show 17.80 % chromium by a userperforming a product analysis. If the product analysis tolerance for such achromium level is 0.20 %, the product analysis of 17.80 % chromiumwould be accepta
30、ble. A product analysis of 17.79 % would not beacceptable.3.1.1.4 proprietary analytical methoda non-standard ana-lytical method, not published by ASTM, utilizing referencestandards traceable to the National Institute of Standards andTechnology (NIST) (when available) or other sources refer-enced in
31、 Section 10.3.1.1.5 referee analysisperformed using ASTM methodslisted in 9.1.1 and NIST reference standards or methods andreference standards agreed upon between parties. The selectionof a laboratory to perform the referee analysis shall be a matterof agreement between the supplier and the purchase
32、r.3.1.1.6 certified reference materiala specimen of materialspecially prepared, analyzed, and certified for chemical contentunder the jurisdiction of a recognized standardizing agency orgroup, such as the National Institute of Standards and Tech-nology, for use by analytical laboratories as an accur
33、ate basisfor comparison. Reference samples should bear sufficientresemblance to the material to be analyzed so that no signifi-cant differences are required in procedures or corrections (forexample, for interferences or inter-element effects).3.1.1.7 working reference materialsreference materialsuse
34、d for routine analytical control and traceable to NISTstandards and other recognized standards when appropriatestandards are available.3.1.2 Pertaining to Elements:4Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.A751 1123
35、.1.2.1 intentionally added unspecified elementan ele-ment added in controlled amounts at the option of the producerto obtain desirable characteristics.3.1.2.2 residual elementa specified or unspecified ele-ment, not intentionally added, originating in raw materials,refractories, or air.3.1.2.3 speci
36、fied elementan element controlled to a speci-fied range, maximum or minimum, in accordance with therequirements of the product specification.3.1.2.4 trace elementa residual element that may occur invery low concentrations, generally less than 0.01 %.4. Concerning the Specification of Chemical Compos
37、itionRequirements4.1 It is recommended that Guide E1282 be consulted as aguide for specifying the chemical compositions for steels.4.2 The recommended practice for specifying chemicalcomposition limits is to limit the number of significant figuresfor each element so that the number of figures to the
38、 right of thedecimal point conforms to the following:ChemicalConcentrationMaximum Number of Figures tothe Right of the Decimal PointUp to 0.010 %, incl. 0.XXXX or may be expressed as ppmOver 0.010 % to0.10 %, incl. 0.XXXOver 0.10 % to 3.0 %,incl. 0.XXOver 3.0 % 0.X4.3 For those cases in which the co
39、mposition range spanseither 0.10 % or 3.0 %, the number of figures to the right of thedecimal is to be determined by that indicated by the upperlimit.4.4 Technical considerations may dictate the employment ofless than the number of figures to the right of the decimal aspreviously recommended.NOTE 3T
40、he recommendations should be employed to reduce thenumber of significant figures, such as from 18.00 % to 18.0 %, but asignificant figure should never be added unless there is a technical reasonfor so doing.5. Cast or Heat Analysis5.1 The producer shall perform analyses for those elementsspecified i
41、n the material specification. The results of suchanalyses shall conform to the requirements specified in thematerial specification.5.1.1 For multiple heats, either individual heat or castanalysis or an average heat or cast analysis shall be reported. Ifsignificant variations in heat or cast size are
42、 involved, aweighted average heat or cast analysis, based on the relativequantity of metal in each heat or cast, shall be reported.5.1.2 For consumable electrode remelted material, a heat isdefined as all the ingots remelted by the same process from aprimary heat. The heat analysis shall be obtained
43、 from oneremelted ingot, or the product of one remelted ingot, from eachprimary melt. If this heat analysis does not meet the heatanalysis requirements of the specification, one sample from theproduct of each remelted ingot shall be analyzed, and theanalyses shall meet the heat analysis requirements
44、.5.2 If the test samples taken for the heat analysis are lost,inadequate, or not representative of the heat, a product analysisof the semifinished or finished product may be used to establishthe heat analysis.5.2.1 If a product analysis is made to establish the heatanalysis, the product analysis sha
45、ll meet the specified limits forheat analysis and the product analysis tolerances described inSection 6 do not apply.6. Product Analysis Requirements6.1 For product analysis, the range of the specified chemicalcomposition is normally greater (designated product analysistolerances) than that applicab
46、le to heat analyses to take intoaccount deviations associated with analytical reproducibilityand the heterogeneity of the steel. If several determinations ofany element in the heat are made, they may not vary bothabove and below the specified range.6.2 Product analysis tolerances may not be used to
47、deter-mine conformance to the specified heat or cast analysis unlesspermitted by the individual material specification.6.3 Product analysis tolerances, where available, are givenin the individual material specifications or in the generalrequirement specifications.7. Unspecified Elements (Note 4)7.1
48、Reporting analyses of unspecified elements is permitted.NOTE 4All commercial metals contain small amounts of variouselements in addition to those which are specified. It is neither practical nornecessary to specify limits for every unspecified element that might bepresent, despite the fact that the
49、presence of many of these elements isoften routinely determined by the producer.7.2 Analysis limits shall be established for specific elementsrather than groups of elements such as “all others,” “rareearths,” and “balance.”8. Sampling8.1 Cast or Heat Analyses:8.1.1 Samples shall be taken, insofar as possible, during thecasting of a heat, at a time which, in the producers judgment,best represents the composition of the cast.8.1.2 In case the heat analysis samples or analyses are lostor inadequate, or when it is evident that the sample does nottruly represent th
