ASTM E1999-2018 Standard Test Method for Analysis of Cast Iron by Spark Atomic Emission Spectrometry.pdf

1、Designation: E1999 18Standard Test Method forAnalysis of Cast Iron by Spark Atomic EmissionSpectrometry1This standard is issued under the fixed designation E1999; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last rev

2、ision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the analysis of cast iron byspark atomic emission spectrometry for the following elementsin the ranges

3、 shown (Note 1):Ranges, %Elements Applicable Range, % Quantitative Range, %ACarbon 1.9 to 3.8 1.90 to 3.8Chromium 0 to 2.0 0.025 to 2.0Copper 0 to 0.75 0.015 to 0.75Manganese 0 to 1.8 0.03 to 1.8Molybdenum 0 to 1.2 0.01 to 1.2Nickel 0 to 2.0 0.02 to 2.0Phosphorus 0 to 0.4 0.005 to 0.4Silicon 0 to 2.

4、5 0.15 to 2.5Sulfur 0 to 0.08 0.01 to 0.08Tin 0 to 0.14 0.004 to 0.14Titanium 0 to 0.12 0.003 to 0.12Vanadium 0 to 0.22 0.008 to 0.22AQuantitative range as directed in Practice E1601.NOTE 1The ranges of the elements listed have been establishedthrough cooperative testing of reference materials. Thes

5、e ranges can beextended by the use of suitable reference materials.1.2 This test method covers analysis of specimens having adiameter adequate to overlap the bore of the spark standopening (to effect an argon seal). The specimen thicknessshould be sufficient to prevent overheating during excitation.

6、 Aheat sink backing may be used. The maximum thickness islimited only by the height that the stand will permit.1.3 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 establish appro-priate safe

7、ty, health, and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of

8、International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2E29 Practice for Using Significant Digits in Test Data toDetermine Conformance with SpecificationsE135 Terminology Relatin

9、g to Analytical Chemistry forMetals, Ores, and Related MaterialsE305 Practice for Establishing and Controlling AtomicEmission Spectrochemical Analytical CurvesE406 Practice for Using Controlled Atmospheres in Spec-trochemical AnalysisE826 Practice for Testing Homogeneity of a Metal Lot orBatch in So

10、lid Form by Spark Atomic Emission Spec-trometryE1329 Practice for Verification and Use of Control Charts inSpectrochemical AnalysisE1601 Practice for Conducting an Interlaboratory Study toEvaluate the Performance of an Analytical MethodE1763 Guide for Interpretation and Use of Results fromInterlabor

11、atory Testing of Chemical Analysis Methods(Withdrawn 2015)3E1806 Practice for Sampling Steel and Iron for Determina-tion of Chemical CompositionE2972 Guide for Production, Testing, and Value Assignmentof In-House Reference Materials for Metals, Ores, andOther Related Materials2.2 Other Documents:MNL

12、 7 Manual on Presentation of Data and Control ChartAnalysis43. Terminology3.1 DefinitionsFor definitions of terms used in this testmethod, refer to Terminology E135.1This test method is under the jurisdiction of ASTM Committee E01 onAnalytical Chemistry for Metals, Ores, and Related Materials and is

13、 the directresponsibility of Subcommittee E01.01 on Iron, Steel, and Ferroalloys.Current edition approved April 15, 2018. Published June 2018. Originallyapproved in 1999. Last previous edition approved in 2011 as E1999 11. DOI:10.1520/E1999-18.2For referenced ASTM standards, visit the ASTM website,

14、www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.4ASTM Manual Series, ASTM Interna

15、tional, 8th Edition, 2010.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles f

16、or theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.14. Summary of Test Method4.1 A capacitor discharge is produced between the flat,ground surface of the disk specimen and a conically shapedelect

17、rode. The discharge is terminated at a predeterminedintensity of a selected iron line, or at a predetermined time, andthe relative radiant energies of the analytical lines are recordedand converted to mass fractions.4.2 Carbon, phosphorus, sulfur and tin emit in the vacuumultraviolet region. The abs

18、orption of the radiation by air in thisregion is overcome by flushing the spark chamber with argonor argon-hydrogen gas mixture and either evacuating thespectrometer or filling the spectrometer with an inert gas suchas nitrogen or argon.NOTE 2It is not within the scope of this test method to prescri

19、bespecific details of every instrument that could be used for the analysis ofcast iron by spark atomic emission spectrometry. The parameters listed inthis test method represent the parameters of the specific instruments usedduring the interlaboratory study to produce the precision and bias listed in

20、this test method. Other spark atomic emission spectrometers with differentparameters may be used provided that they produce equivalent or betterprecision and bias data.5. Significance and Use5.1 The chemical composition of cast iron alloys shall bedetermined accurately in order to insure the desired

21、 metallur-gical properties. This procedure is suitable for manufacturingcontrol and inspection testing.6. Interferences6.1 Interferences may vary with spectrometer design andexcitation characteristics. Direct spectral interferences may bepresent on one or more of the wavelengths listed in this testm

22、ethod. Frequently, these interferences shall be determinedand proper corrections made by the use of various referencematerials. Refer to Table 1 for possible interferences. Thecomposition of the sample being analyzed should matchclosely the composition of one or more of the referencematerials used t

23、o prepare and control the calibration curve.Alternatively, mathematical corrections may be used to solvefor interelement effects. Various mathematical correction pro-cedures are commonly utilized. Any of these correction proce-dures that produce precision and accuracy results equal to orbetter than

24、the results in the interlaboratory study for this testmethod are acceptable.7. Apparatus7.1 When required, use sample preparation equipment asfollows:7.1.1 Sample Mold, to produce graphite-free white chillediron samples that are homogeneous, free of voids or porosity inthe region to be excited, and

25、representative of the material to beanalyzed. A chill-cast disk approximately 40 mm (112 in.) indiameter and 3-mm to 12-mm (18-in. to12-in.) thick issatisfactory. A sample mold made from copper with a lowoxygen content has proven to be optimum for this purpose.Refer to Practice E1806 for iron sampli

26、ng procedures.7.1.2 Surface Grinder or Sander with Abrasive Belts orDisks, capable of providing a flat, clean, uniform surface on thereference materials and specimens.7.2 Excitation Source, capable of providing sufficient en-ergy to sample the specimen and excite the analytes of interest.Any other e

27、xcitation source whose performance has beenproven to be equivalent may be used.7.3 Excitation Chamber, automatically flushed with argon orother inert gas. Clean the excitation chamber when the counterelectrode is replaced.7.3.1 Clean the lens or protective window as recommendedby the instrument manu

28、facturer.7.4 Spectrometer, having sufficient resolving power andlinear dispersion to separate clearly the analytical lines fromother lines in the spectrum in the spectral region 170.0 nm to520.0 nm. The spectrometers used to test this method had adispersion of 0.3 nm/mm to 0.6 nm/mm and a focal leng

29、th of0.5 m to 0.75 m. Spectral lines are listed in Table 1. Theprimary slit width is 15 m to 50 m. Secondary slit width is15 m to 200 m. The spectrometer shall be provided with oneor more of the following:TABLE 1 Analytical and Internal Standard Lines,Possible InterferencesElement Wavelength, nm Rep

30、orted PossibleInterferingElementsCarbon 193.09 Al, Mo, Cu, SChromium 267.72 Mo, S, Mn265.86Copper 211.21 Ni221.81327.40 Mo, P510.55 VManganese 293.31 Cr, Mo, WMolybdenum 202.03 Ni281.61 MnNickel 243.79 Mn231.60 Mn341.48352.45 MoPhosphorus 178.29 Cr, Mn, Mo, CuSilicon 212.41 Mo, Cu, Ni251.61288.16 Mo

31、, CrSulfur 180.73 Mn, Cu, CrTin 189.99 Mn, Mo, FeTitanium 334.90 Cr337.28 Fe334.19Vanadium 310.23 Ni311.07IronA273.07271.44281.33360.89AInternal standard.E1999 1827.4.1 An air/gas inlet and a vacuum outlet. The spectrometershall be operated at a vacuum of 25 m of mercury or below.7.4.2 A gas inlet a

32、nd a gas outlet.7.4.3 Sealed with nitrogen or other inert gas.7.5 Measuring System, consisting of photomultipliers hav-ing individual voltage adjustment, capacitors on which theoutput of each photomultiplier is stored and an electronicsystem to measure voltages on the capacitors either directly orin

33、directly, and the necessary switching arrangements to pro-vide the desired sequence of operation.7.6 Readout Console or Computer, capable of indicating theratio of the analytical lines to the internal standard withsufficient precision to produce the accuracy of analysis desired.7.7 Gas System, consi

34、sting of an argon or argon-hydrogensupply with pressure and flow regulation. Automatic sequenc-ing shall be provided to actuate the flow at a given rate for aspecific time interval. The flow rate may be manually orautomatically controlled. The gas system shall meet the re-quirements of Practice E406

35、.7.8 Vacuum Pump, if required, capable of maintaining avacuum of 25 m Hg or less.NOTE 3A pump with a displacement of at least 0.23 m3/min (8ft3/min) is usually adequate.8. Reagents and Materials8.1 Inert Gas (Argon, Nitrogen), or Hydrogen, as required,shall be of sufficient purity to permit proper e

36、xcitation of theanalytical lines of interest in the excitation chamber and topermit light transmittance in the spectrometer chamber. Use asdirected in Practice E406.8.2 Counter ElectrodesA silver or tungsten rod of 2-mmto 6-mm diameter ground to a 30 to 90 conical tip. Othermaterial may be used prov

37、ided it can be shown experimentallythat equivalent precision and accuracy are obtained.8.2.1 A black deposit may build up on the tip of theelectrode, thus reducing the overall intensity of the spectralradiation. The number of acceptable excitations on an electrodevaries from one instrument to anothe

38、r and should be deter-mined in each laboratory. Cleaning of the electrodes after eachburn significantly reduces this buildup and gives more consis-tent results.9. Calibration Reference Materials (RMs)9.1 These can come in three forms: certified referencematerials, reference materials, and analyzed p

39、roductionsamples. In selecting calibration RMs, use caution with com-positions that are unusual. One element may adversely influ-ence the radiant energy of another element or its uniformity ofdistribution within the material. Tests should be made todetermine if interrelations exist between elements

40、in thecalibration RMs. To compensate for inter-element effects, it issuggested that the calibration RMs approximate the composi-tion of the material to be tested. The metallurgical history ofthe calibration RMs should be similar to that of the specimensbeing analyzed as directed in Practice E305.9.2

41、 Certified Reference Materials (CRMs), used as calibra-tion RMs for chill-cast iron alloys and are available commer-cially.9.3 Reference Materials (RMs), used as calibration RMs forchill-cast iron alloys and are available commercially.NOTE 4The distinction is made between CRMs and productionmaterial

42、s because there are commercially available RMs produced byreputable producers that do not claim to be CRMs but in all other respectsfit the definition of CRMs. Refer to Guide E2972 for additional informa-tion regarding reference materials.9.4 Analyzed Production Samples shall be chemically ana-lyzed

43、 test specimens taken from production heats produced asdirected in Practice E1806. They shall cover the mass fractionranges of the elements to be determined and shall include all ofthe specific types of alloys being analyzed. These calibrationRMs shall be homogeneous and free of voids and porosity.R

44、efer to Practice E826 for information on homogeneity testingof reference materials using spark atomic emission spectrom-etry.10. Preparation of Calibration RMs and Specimens10.1 Specimens, cast graphite-free specimens from moltenmetal into a suitable mold and cool. Refer to Practice E1806for informa

45、tion on the preparation of specimens for analysis.10.2 Preparation, prepare the surface to be analyzed on asuitable belt or disk grinder. Prepare the surface of thespecimens and calibration RMs in a similar manner. Allspecimens shall be free of moisture, oil, and residue for properexcitation.10.3 Sp

46、ecimen porosity is undesirable because it leads tothe “diffuse-type” rather than the desired “concentrated-type”discharge. The specimen surface should be kept clean becausethe specimen is the electron emitter, and electron emission isinhibited by oily, dirty surfaces.10.4 Calibration RMs and specime

47、ns shall be refinished dryon a belt or disc sander before being re-excited on the samearea.11. Specimen Excitation Parameters11.1 Operate the spectrometer as directed by the manufac-turers instructions. When the parameters in 11.1.1 areestablished, maintain them carefully. The variation of thepower

48、supply voltage shall not exceed 6 5 % and preferablyshould be held within 6 2%.11.1.1 An example of excitation parameters for a high-energy unidirectional spark source is listed below:Preburn IntegrationCapacitance, F 10 10Inductance, H 20 20Resistance, 04.4Potential, V 550 350Number of discharges/s

49、 120 60E1999 18311.2 Spark Conditions (11.2.1)An example of spark pa-rameters is listed below:Flush period, s 2 to 10Preburn period, s 5 to 20Integration period, s 5 to 20Gas Flow ft3/h L/minFlush 5 to 45 2.5 to 25Preburn 5 to 45 2.5 to 25Integration 5 to 30 2.5 to 1511.2.1 Select preburn and integration periods after a studyof volatization rates during specimen excitation. Onceestablished, maintain the parameters consistently. The instru-ment manufacturer can normally provide this information.11.3 Electrode System For conventional capacitor dis-charge exc