1、Designation: A 751 08Standard Test Methods, Practices, and Terminology forChemical Analysis of Steel Products1This standard is issued under the fixed designation A 751; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of la
2、st 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 term
3、inology 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
5、 steel, 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 r
6、elatedalloys. 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 t
7、erminology 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 terminolog
8、y.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 est
9、ablish 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
10、of Steel, CastIron, Open-Hearth Iron, and Wrought Iron3E50 Practices for Apparatus, Reagents, and Safety Consid-erations for Chemical Analysis of Metals, Ores, andRelated MaterialsE59 Practice for Sampling Steel and Iron for Determinationof Chemical Composition3E60 Practice for Analysis of Metals, O
11、res, and RelatedMaterials by Molecular Absorption SpectrometryE 212 Test Method for Spectrographic Analysis of Carbonand Low-Alloy Steel by the Rod-To-Rod Technique3E 293 Test Method for Spectrographic Determination ofAcid-Soluble Aluminum in Low-Alloy Steel by the Solu-tion Technique3E 322 Test Met
12、hod for X-Ray Emission SpectrometricAnalysis of Low-Alloy Steels and Cast IronsE 327 Test Method for Optical Emission SpectrometricAnalysis of Stainless Type 18-8 Steels by the Point-To-Plane Technique3E 350 Test Methods for ChemicalAnalysis of Carbon Steel,Low-Alloy Steel, Silicon Electrical Steel,
13、 Ingot Iron, andWrought Iron1These 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
14、and Processes.Current edition approved Oct. 1, 2008. Published October 2008. Originallyapproved in 1977. Last previous edition approved in 2007 as A 751 07a.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of AS
15、TMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.E 352 Test M
16、ethods for Chemical Analysis of Tool Steelsand Other Similar Medium- and High-Alloy SteelsE 353 Test Methods for Chemical Analysis of Stainless,Heat-Resisting, Maraging, and Other Similar Chromium-Nickel-Iron AlloysE 354 Test Methods for Chemical Analysis of High-Temperature, Electrical, Magnetic, a
17、nd Other Similar Iron,Nickel, and Cobalt AlloysE 403 Method for Optical Emission Spetrometric Analysisof Carbon and Low-Alloy Steel by the Point-To-PlaneTechnique3E 404 Test Method for Spectrographic Determination ofBoron In Carbon and LowAlloy Steel by the Point-To-Plane Technique3E 415 Test Method
18、 for Atomic Emission Vacuum Spectro-metric Analysis of Carbon and Low-Alloy SteelE 421 Test Method for Spectrographic Determination ofSilicon and Aluminum in High-Purity Iron3E 485 Test Method for Optical Emission Vacuum Spectro-metricAnalysis of Blast Furnace Iron by the Point-to-PlaneTechniqueE 54
19、8 Guide for General Criteria Used for EvaluatingLaboratory Competence3E 572 Test Method for Analysis of Stainless and AlloySteels by X-ray Fluorescence SpectrometryE 663 Practice for Flame Atomic Absorption Analysis3E 743 Guide for Spectrochemical Laboratory Quality As-surance3E 851 Practice for Eva
20、luation of Spectrochemical laborato-ries3E 882 Guide for Accountability and Quality Control in theChemical Analysis LaboratoryE 1019 Test Methods for Determination of Carbon, Sulfur,Nitrogen, and Oxygen in Steel and in Iron, Nickel, andCobalt AlloysE 1024 Guide for Chemical Analysis of Metals and Me
21、talBearing Ores by Flame Atomic Absorption Spectropho-tometry3E 1063 Test Method for X-Ray Emission SpectrometricDetermination of Cerium and Lanthanum in Carbon andLow-Alloy Steel3E 1085 Test Method for X-Ray Emission SpectrometricAnalysis of Low-Alloy SteelsE 1086 Test Method for Optical Emission V
22、acuum Spectro-metric Analysis of Stainless Steel by Point-to-Plane Exci-tation TechniqueE 1087 Practice for Sampling Molten Steel From a LadleUsing an Immersion Sampler to Produce a Specimen forEmission Spectrochemical Analysis3E 1097 Guide for Direct Current Plasma-Atomic EmissionSpectrometry Analy
23、sisE 1184 Practice for Electrothermal (Graphite Furnace)Atomic Absorption AnalysisE 1282 Guide for Specifying the Chemical Compositionsand Selecting Sampling Practices and Quantitative Analy-sis Methods for Metals, Ores, and Related MaterialsE 1329 Practice for Verification and Use of Control Charts
24、in Spectrochemical Analysis2.2 ISO Standards4ISO/IEC 17025 General Requirements for the Competenceof Testing and Calibration Laboratories3. 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 st
25、eel as reportedto the purchaser and determined by analyzing a test sample,preferably obtained during the pouring of the steel, for theelements designated in a specification.3.1.1.2 product, check or verification analysisa chemicalanalysis of the semifinished or finished product, usually for thepurpo
26、se of determining conformance to the specification re-quirements. The range of the specified composition applicableto product analysis is normally greater than that applicable toheat analysis in order to take into account deviations associatedwith analytical reproducibility (Note 1) and the heteroge
27、neityof the steel.NOTE 1All of the chemical analysis procedures referenced in thisdocument include precision statements with reproducibility data with theexception of Test Methods E 30.3.1.1.3 product analysis tolerances (Note 2)a permissiblevariation over the maximum limit or under the minimum limi
28、tof a specified element and applicable only to product analyses,not cast or heat analyses.NOTE 2The term “analysis tolerance” is often misunderstood. It doesnot apply to cast or heat analyses determined to show conformance tospecified chemical limits. It applies only to product analysis and becomesm
29、eaningful only when the heat analysis of an element falls close to one ofthe specified limits. For example, stainless steel UNS 30400 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 anal
30、ysis. If the product analysis tolerance for such achromium level is 0.20 %, the product analysis of 17.80 % chromiumwould be acceptable. 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 refer
31、encestandards traceable to the National Institute of Standards andTechnology (NIST) (when available) or other sources refer-enced in 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 parti
32、es. The selectionof a laboratory to perform the referee analysis shall be a matterof agreement between the supplier and the purchaser.3.1.1.6 certified reference materiala specimen of materialspecially prepared, analyzed, and certified for chemical contentunder the jurisdiction of a recognized stand
33、ardizing agency orgroup, such as the National Institute of Standards and Tech-nology, for use by analytical laboratories as an accurate basisfor comparison. Reference samples should bear sufficient4Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10
34、036, http:/www.ansi.org.A751082resemblance 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 materialsused for routine analytical control a
35、nd traceable to NISTstandards and other recognized standards when appropriatestandards are available.3.1.2 Pertaining to Elements:3.1.2.1 intentionally added unspecified elementan ele-ment added in controlled amounts at the option of the producerto obtain desirable characteristics.3.1.2.2 residual e
36、lementa specified or unspecified ele-ment, not intentionally added, originating in raw materials,refractories, or air.3.1.2.3 specified 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 resid
37、ual element that may occur invery low concentrations, generally less than 0.01 %.4. Concerning the Specification of Chemical CompositionRequirements4.1 It is recommended that Guide E 1282 be consulted as aguide for specifying the chemical compositions for steels.4.2 The recommended practice for spec
38、ifying chemicalcomposition limits is to limit the number of significant figuresfor each element so that the number of figures to the 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 b
39、e 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 composition 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 cons
40、iderations may dictate the employment ofless than the number of figures to the right of the decimal aspreviously recommended.NOTE 3The 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 t
41、here is a technical reasonfor so doing.5. Cast or Heat Analysis5.1 The producer shall perform analyses for those elementsspecified in the material specification. The results of suchanalyses shall conform to the requirements specified in thematerial specification.5.1.1 For multiple heats, either indi
42、vidual heat or castanalysis or an average heat or cast analysis shall be reported. Ifsignificant variations in heat or cast size are 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 remelt
43、ed material, a heat isdefined as all the ingots remelted by the same process from aprimary heat. The heat analysis shall be obtained 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 specifica
44、tion, one sample from theproduct of each remelted ingot shall be analyzed, and theanalyses shall meet the heat analysis requirements.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 m
45、ay be used to establishthe heat analysis.5.2.1 If a product analysis is made to establish the heatanalysis, the product analysis shall meet the specified limits forheat analysis and the product analysis tolerances described inSection 6 do not apply.6. Product Analysis Requirements6.1 For product ana
46、lysis, the range of the specified chemicalcomposition is normally greater (designated product analysistolerances) than that applicable to heat analyses to take intoaccount deviations associated with analytical reproducibilityand the heterogeneity of the steel. If several determinations ofany element
47、 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 deter-mine conformance to the specified heat or cast analysis unlesspermitted by the individual material specification.6.3 Product analysis tolerances, where available,
48、 are givenin the individual material specifications or in the generalrequirement specifications.7. Unspecified Elements (Note 4)7.1 Reporting analyses of unspecified elements is permitted.NOTE 4All commercial metals contain small amounts of variouselements in addition to those which are specified. I
49、t is neither practical nornecessary to specify limits for every unspecified element that might bepresent, despite the fact that the 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 I
