1、Designation: E1999 11Standard 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 concen
3、tration ranges shown (Note 1):Concentration 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
4、 0.005 to 0.4Silicon 0 to 2.5 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 0.22_AQuantitative range in accordance with Practice E1601.NOTE 1The concentration ranges of the elements listed have beenestablished through c
5、ooperative testing of reference materials. Theseconcentration ranges can be extended by the use of suitable referencematerials.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 thicknesssh
6、ould be sufficient to prevent overheating during excitation. 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
7、 of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E135 Terminology Relating to Analytical Chemistry forMetals, Ores, and Related MaterialsE158 Practice
8、 for Fundamental Calculations to ConvertIntensities into Concentrations in Optical Emission Spec-trochemical Analysis3E172 Practice for Describing and Specifying the ExcitationSource in Emission Spectrochemical Analysis3E305 Practice for Establishing and Controlling AtomicEmission Spectrochemical An
9、alytical CurvesE351 Test Methods for Chemical Analysis of Cast IronAll TypesE406 Practice for Using Controlled Atmospheres in Spec-trochemical AnalysisE826 Practice for Testing Homogeneity of a Metal Lot orBatch in Solid Form by Spark Atomic Emission Spectrom-etryE1019 Test Methods for Determination
10、 of Carbon, Sulfur,Nitrogen, and Oxygen in Steel, Iron, Nickel, and CobaltAlloys by Various Combustion and Fusion TechniquesE1329 Practice for Verification and Use of Control Charts inSpectrochemical AnalysisE1601 Practice for Conducting an Interlaboratory Study toEvaluate the Performance of an Anal
11、ytical MethodE1763 Guide for Interpretation and Use of Results fromInterlaboratory Testing of Chemical Analysis MethodsE1806 Practice for Sampling Steel and Iron for Determina-tion of Chemical Composition1This test method is under the jurisdiction of ASTM Committee E01 onAnalytical Chemistry for Met
12、als, Ores, and Related Materials and is the directresponsibility of Subcommittee E01.01 on Iron, Steel, and Ferroalloys.Current edition approved May 15, 2011. Published July 2011. Originallyapproved in 1999. Last previous edition approved in 2004 as E1999 99 (2004).DOI: 10.1520/E1999-112For referenc
13、ed ASTM standards, visit the ASTM website, 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.3Withdrawn. The last approved version of this historical standard is refer
14、encedon www.astm.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.2.2 Other Documents:MNL 7A Manual on Presentation of Data and Control ChartAnalysis43. Terminology3.1 Definitions For definitions of terms used in this testmethod,
15、refer to Terminology E135.4. Summary of Test Method4.1 A capacitor discharge is produced between the flat,ground surface of the disk specimen and a conically shapedelectrode. The discharge is terminated at a predeterminedintensity of a selected iron line, or at a predetermined time, andthe relative
16、radiant energies of the analytical lines are recordedand converted to concentration.4.2 Carbon, phosphorus, sulfur and tin emit in the vacuumultraviolet region. The absorption of the radiation by air in thisregion is overcome by flushing the spark chamber with argonor argon-hydrogen gas mixture and
17、either evacuating thespectrometer or filling the spectrometer with an inert gas suchas nitrogen or argon. A capacitor discharge is producedbetween the flat, ground surface of the disk specimen and aconically shaped electrode. The discharge is terminated at apredetermined intensity of a selected iron
18、 line, or at a prede-termined time, and the relative radiant energies of the analyti-cal lines are recorded and converted to concentration.NOTE 2It is not within the scope of this test method to prescribespecific details of every instrument that could be used for the analysis ofcast iron by spark at
19、omic 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 inthis test method. Other spark atomic emission spectrometers with differentparameters may be used p
20、rovided that they produce equivalent or betterprecision and bias data5. Significance and Use5.1 The chemical composition of cast iron alloys shall bedetermined accurately in order to insure the desired metallur-gical properties. This procedure is suitable for manufacturingcontrol and inspection test
21、ing.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 a method.Frequently, these interferences shall be determined and propercorrections made by the use of various
22、 reference materials.Refer to Table 1 for possible interferences. The composition ofthe sample being analyzed should match closely the composi-tion of one or more of the reference materials used to prepareand control the calibration curve. Alternatively, mathematicalcorrections may be used to solve
23、for interelement effects (referto Practice E158). Various mathematical correction proceduresare commonly utilized. Any of these correction procedures thatproduce precision and accuracy results equal to or better thanthe results in the interlaboratory study for this test method areacceptable.7. Appar
24、atus7.1 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 representative of the material to beanalyzed. A chill-cast disk approximately 40 mm
25、(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 sampling procedures.7.1.2 Surface Grinder or Sander with Abrasive Belts orDisks, capable o
26、f 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.See Practice E172. Any other excitation source whose perfor-mance has been proven to be equival
27、ent may be used.7.3 Excitation Chamber, automatically flushed with argonor other inert gas. Clean the excitation chamber when thecounter electrode is replaced.4ASTM Manual Series, ASTM, 6th Edition, 1990.TABLE 1 Analytical and Internal Standard Lines, PossibleInterferencesElement Wavelength, nm Repo
28、rted 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,
29、 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 112NOTE 3Clean the lens or protective window as recommended by theinstrument manufacturer.7.4 Spectrometer, having sufficient resolving power
30、 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 length of0.5 m to 0.75 m. Spectral lines are listed in Table 1.
31、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:7.4.1 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 and a gas outlet.7.
32、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 orindirectly, and the
33、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, consisting of an argon
34、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 be in accor-dance with Practice E406.7.8 Vacuum Pump, if
35、required, capable of maintaining avacuum of 25 m Hg or less.NOTE 4A pump with a displacement of at least 0.23 m3/min (8 ft3/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 excitation of theanal
36、ytical lines of interest in the excitation chamber or lighttransmittance in the spectrometer chamber. Use in accordancewith Practice E406.8.2 Counter ElectrodesA silver or thoriated tungsten rodof 2-mm to 6-mm diameter ground to a 30 to 90 conical tip.Other material may be used provided it can be sh
37、own experi-mentally that equivalent precision and accuracy are obtained.NOTE 5A black deposit may build up on the tip of the electrode, thusreducing the overall intensity of the spectral radiation. The number ofacceptable excitations on an electrode varies from one instrument toanother and should be
38、 determined in each laboratory. Cleaning electrodesafter each burn significantly reduces this buildup and gives more consis-tent results.9. Calibrants9.1 Calibrants can come in three forms: certified referencematerials, reference materials, and analyzed productionsamples. In selecting calibrants, us
39、e caution with compositionsthat are unusual. One element may adversely influence theradiant energy of another element or its uniformity of distri-bution within the material. Tests should be made to determineif interrelations exist between elements in the calibrants. Tocompensate for inter-element ef
40、fects, it is suggested that thecalibrants approximate the composition of the material to betested. The metallurgical history of the calibrants should besimilar to that of the specimens being analyzed in accordancewith the recommendations of Practice E305.9.2 Certified Reference Materials (CRMs), use
41、d as cali-brants for chill-cast iron alloys are available commercially.9.3 Reference Materials (RMs), used as calibrants forchill-cast iron alloys are available commercially.NOTE 6The distinction is made between CRMs and productionmaterials because there are commercially available RMs produced byrep
42、utable producers that do not claim to be CRMs but in all other respectsfit the definition of CRMs.9.4 Analyzed Production Samples shall be chemically ana-lyzed test specimens taken from production heats producedaccording to Practice E1806. They shall cover the concentra-tion ranges of the elements t
43、o be determined and shall includeall of the specific types of alloys being analyzed. Thesecalibrants shall be homogeneous and free of voids and porosity.Refer to Test Methods E351 and E1019 or other nationallyaccepted test methods for chemical analysis of iron base alloys.Refer to Practice E826 for
44、information on homogeneity testingof reference materials.10. Preparation of Calibrants and Specimens10.1 Specimens, cast graphite-free specimens from moltenmetal into a suitable mold and cool. Refer to Practice E1806for information on the preparation of specimens for analysis.10.2 Preparation, prepa
45、re the surface to be analyzed on asuitable belt or disk grinder. Prepare the surface of thespecimens and calibrants in a similar manner. All specimensshall be free of moisture, oil, and residue for proper excitation.10.3 Specimen porosity is undesirable because it leads tothe “diffuse-type” rather t
46、han 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 Calibrants and specimens shall be refinished dry on abelt or disc sander before being re-excited on the
47、same area.11. Specimen Excitation Parameters11.1 Operate the spectrometer according to the manufactur-ers instructions.NOTE 7When parameters are established, maintain them carefully.The variation of the power supply voltage shall not exceed 65 % andpreferably should be held within 62%.11.1.1 An exam
48、ple of excitation parameters for a high-energy unidirectional spark source is listed below:Preburn ExposureCapacitance, F 10 10Inductance, H 20 20Resistance, V 04.4Potential, V 550 350Number of discharges/s 120 6011.2 Spark Conditions (Note 8)An example of sparkparameters is listed below:Flush perio
49、d, s 2 to 10E1999 113Preburn period, s 5 to 20Exposure period, s 5 to 20Gas Flow ft3/h L/minFlush 5 to 45 2.5 to 25Preburn 5 to 45 2.5 to 25Exposure 5 to 30 2.5 to 15NOTE 8Select preburn and exposure periods after a study of volati-zation rates during specimen excitation. Once established, maintain theparameters consistently. The instrument manufacturer can normally pro-vide this information.11.3 Electrode System For conventional capacitor dis-charge excitation systems, the specimen, electrically negative,serves as one electrode. The opposi
