1、Designation: E2626 081Standard Guide forSpectrometric Analysis of Reactive and Refractory Metals1This standard is issued under the fixed designation E2626; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision.
2、A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1NOTEEditorial corrections were made throughout in October 2009.1. Scope1.1 This guide covers a variety of analytical techniques thathave proven
3、to be acceptable for the analysis of the reactiveand refractory metals titanium, zirconium, niobium, hafnium,tantalum, molybdenum, tungsten, and vanadium.1.2 The principles and techniques in this guide can be usedby ISO 17025 compliant laboratories that need to implementother performance-based test
4、methods or need to document andvalidate extensions of standard test methods, or non-standardtest methods.1.3 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.4 This standard does not purport to address all of thesafety concerns
5、, if any, associated with its use. It is theresponsibility 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:2D1193 Specification for Reagent WaterE50 Pr
6、actices for Apparatus, Reagents, and Safety Consid-erations for Chemical Analysis of Metals, Ores, andRelated MaterialsE135 Terminology Relating to Analytical Chemistry forMetals, Ores, and Related MaterialsE539 Test Method forAnalysis of TitaniumAlloys by X-RayFluorescence SpectrometryE882 Guide fo
7、r Accountability and Quality Control in theChemical Analysis LaboratoryE1097 Guide for Determination of Various Elements byDirect Current Plasma Atomic Emission SpectrometryE1184 Practice for Determination of Elements by GraphiteFurnace Atomic Absorption SpectrometryE1479 Practice for Describing and
8、 Specifying Inductively-Coupled Plasma Atomic Emission SpectrometersE1552 Test Method for Determining Hafnium in Zirconiumand ZirconiumAlloys By Direct Current PlasmaAtomicEmission SpectrometryE1601 Practice for Conducting an Interlaboratory Study toEvaluate the Performance of an Analytical MethodE1
9、621 Guide for X-Ray Emission Spectrometric AnalysisE1770 Practice for Optimization of Electrothermal AtomicAbsorption Spectrometric EquipmentE2371 Test Method for Analysis of Titanium and TitaniumAlloys by Atomic Emission Plasma SpectrometryE2437 Practice for Designing and Validating Performance-Bas
10、ed Test Methods for the Analysis of Metals, Ores, andRelated MaterialsE2438 Practice for Implementing Standard PerformanceBased Test Methods for the Analysis of Metals, Ores, andRelated Materials2.2 ISO Standards:3ISO 17025 General Requirements for the Competence ofTesting and Calibration Laboratori
11、esISO Guide 32 Calibration in Analytical Chemistry and Useof Certified Reference Materials3. Terminology3.1 DefinitionsFor definitions of terms used in this guide,refer to Terminology E135.3.2 Definitions of Terms Specific to This Standard:3.2.1 reactive metal, na metal, such as titanium orzirconium
12、, that readily reacts with the environment. It has astrong affinity for oxygen and nitrogen and forms very stablecompounds that passivate in thin layers. When the reactivecoating is damaged, it self heals by reaction with the atmo-sphere.1This guide is under the jurisdiction of ASTM Committee E01 on
13、 AnalyticalChemistry for Metals, Ores, and Related Materials and is the direct responsibility ofSubcommittee E01.06 on Ti, Zr, W, Mo, Ta, Nb, Hf, Re.Current edition approved June 15, 2008. Published July 2008. DOI: 10.1520/E2626-08E01.2For referenced ASTM standards, visit the ASTM website, www.astm.
14、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.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org
15、.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesNOTICE: This standard has either been superseded and replaced by a new version or withdrawn.Contact ASTM International (www.astm.org) for the latest information13.2.2 refractory metal, n
16、a metal, such as hafnium,molybdenum, niobium, tantalum, vanadium, or tungsten, char-acterized by very high melting points, above about 1900 C,that oxidizes at temperatures far below its melting point.4. Significance and Use4.1 Test methods for chemical analysis of reactive andrefractory metals are p
17、rimarily intended to test such materialsfor compliance with compositional specifications. It is assumedthat all who use this guide will be trained analysts capable ofperforming common laboratory procedures skillfully andsafely. It is expected that work will be performed in a properlyequipped laborat
18、ory under appropriate quality control practicessuch as those described in Guide E882 and Practice E2437,aswell as in ISO 17025 and ISO Guide 32.4.2 This guide is intended to aid analytical chemistrylaboratories in the analysis of reactive and refractory metalsand their alloys when no specific standa
19、rd test methods areavailable. The principles incorporated in this practice can alsobe applied in laboratories that wish to validate and documentnon-standard test methods.4.3 The analysis of reactive and refractory materials istypically performed by only a small number of laboratories.Few of these la
20、boratories have analytical instrumentation incommon for use in interlaboratory proficiency testing pro-grams. This requires the use of within-laboratory developedtest methods that vary between laboratories. It is intended thatthis practice will give general guidance to experienced person-nel that wi
21、ll assist them in the development of a procedure thatwill meet their analytical objectives.4.4 Practice E2438 provides guidance for the developmentand documentation of an In-House Standard Operating Proce-dure (SOP).5. Hazards5.1 The dissolution of these metals usually requires the useof hydrofluori
22、c acid. Read and follow label precautions andmandatory safety data sheet (MSDS) information, and refer toPractices E50.5.2 Fine turnings, chips, or powder require more water tomoderate the reaction rate. If the metal is solid chunks ratherthan finely divided, the dissolution will be much slower andr
23、equire less water. It will also require additional acid tocomplete the dissolution. See Specification D1193 for reagentwater specifications.5.3 Fine turnings or powder of hafnium, titanium, andzirconium are pyrophoric. Observe the proper precautions.6. Test Methods6.1 Atomic Absorption Spectrometry
24、(AAS)This techniqueis applicable to elements that can be dissolved and placed in thevapor state (flame or flameless) as ground state atoms. Radia-tion from a hollow cathode light source emits the spectrum ofthe element to be analyzed, which is then passed through vaporcontaining the element to be an
25、alyzed, and into a monochro-mator set for radiation characteristic of the element. The degreeof absorption is measured, and is proportional to the amount ofthe particular element present.Analysis is made by comparisonto reference materials. Lists of elements that can bedetermined, sensitivities, wav
26、elengths, and operating param-eters are provided by the instrument manufacturers. Due to therequirements of the materials specifications, theAAS detectionlimits for many elements will not be low enough for the use ofthis technique. AAS has been utilized for the analysis of iron,chromium, nickel, and
27、 tin in zirconium alloys and for thedetermination of iron and zirconium in hafnium. PracticesE1184 and E1770 provide further details.6.2 Atomic Emission Spectrometry (AES)This techniquehas historically been the main means of analysis for thesemetals. Analysis by the techniques described in this sect
28、ion isbased upon the fact that each vaporized element, when suitablyexcited by an arc, spark, plasma, or other means, is made toemit its characteristic spectrum. The radiation thus emittedpasses into a spectrometer where it is resolved into itscomponent wavelengths and recorded by various means as a
29、definite pattern. The position of the spectral informationindicates QUALITATIVELY which elements are present. Theintensity determines QUANTITATIVELY the amount of eachelement in the sample when compared to intensities obtainedby using calibration materials. Calibration materials can bereference mate
30、rials or industry acceptable analyzed specimens.6.2.1 Arc/Spark Spectrometry (AS-AES)Instruments uti-lizing photographic film or plates were the mainstay for manyyears until parts and supplies became very difficult, if notimpossible, to obtain. Electronic read-out arc/spark instrumentsare still used
31、 by a number of laboratories. The primary problemwith arc/spark is the unavailability of solid reference materialsfor calibration. Metallurgical history and surface grain sizeeffects can become an issue. However, if proper calibrationmaterials were available, the majority of the necessary ele-ments
32、in a typical material specification could be analyzed.6.2.2 Direct Current Plasma Atomic Emission Spectrometry(DCP-AES)Since DCP-AES analysis, like atomicabsorption, Inductively Coupled Plasma Atomic EmissionSpectrometry (ICP-AES) (see 6.2.3), and Inductively CoupledPlasma-Mass Spectrometry (ICP-MS)
33、 (see 6.2.4), relies onsample dissolution, the major difficulties with reference mate-rials for calibration with can be overcome by the techniquesdiscussed in 9.4. One of the main positive attributes of thistechnique is the high resolution available due to the Echellegrating. The highly complex spec
34、tra of reactive and refractorymetals require an instrument with good spectral resolvingpower in order to find interference-free wavelengths. TheDCP-AES has a rugged sample introduction system that lendsitself well to the analysis of materials that have been dissolvedin acids such as hydrofluoric, ni
35、tric, and hydrochloric acids. Inmost cases, due to the nature of the source design, theDCP-AES does not achieve the detection limits or the precisionof an Inductively Coupled Plasma (ICP) source. In some cases,however, its significantly superior resolving power may allowit to out-perform an ICP that
36、 utilizes a conventional ruledgrating. The corrosion resistant nature of the sample introduc-tion system and jet materials on DCP-AES has allowed it to bevery capable for the analysis of silicon in a hydrofluoric acidE2626 0812solution. DCP-AES is unable to achieve the necessary detec-tion limits fo
37、r elements such as boron and cadmium in azirconium sample at the levels required by most specifications.Test Method E1552 gives details for the analysis of hafnium inzirconium and zirconium alloys using the DCP-AES techniqueand Test Method E2371 describes the analysis of titanium andtitanium alloys.
38、 Guide E1097 discusses the technique in moregeneral terms.6.2.3 Inductively Coupled Plasma Atomic Emission Spec-trometry (ICP-AES)Practice E1479 describes the compo-nents of an ICP-AES that are basic to its operation and to thequality of its performance. ICP-AES and ICP-MS represent theinstruments m
39、ost commonly used for the analysis of reactiveand refractory metals. These solution-based techniquescomplement each other to provide a reliable means of analysisof reactive and refractory metals. Care must always be taken toavoid serious spectral interferences due to the line-rich natureof reactive
40、and refractory metals. The advent of solid-statedetectors has provided much flexibility in the selection ofwavelengths. Section 8.3 gives guidance in wavelength selec-tion. Test Method E2371 gives details for the analysis oftitanium and titanium alloys, while Practice E1479 discussesthe techniques i
41、n more general terms.6.2.4 Inductively Coupled Plasma-Mass Spectrometry (ICP-MS)This technique is distinguished from ICP-AES by thedetection system used to analyze the species excited by aplasma. A mass spectrometer is utilized in this case. Much ofthe information in Practice E1479 is applicable to
42、ICP-MS.This technique is capable of analyzing the majority of the metalelements necessary to satisfy the material specifications forreactive and refractory metals. The high sensitivity of ICP-MSmay require significant dilution of the sample solution in orderto analyze elements at concentrations abov
43、e 0.1 %, by mass.6.3 Glow Discharge SpectrometryThe issue mentionedabove in securing solid reference materials is a concern thatmust be addressed with this technique. Glow Discharge instru-mentation is normally divided into two types of instrumenta-tion.6.3.1 Glow Discharge-Mass Spectrometry (GD-MS)
44、Inthis technique, the surface of a solid sample is sputtered withargon gas. Ionized species are then subjected to high-resolutionmass spectrometric analysis. This results in the high sensitivityanalysis of all elements in the periodic table, except hydrogenat the trace level. GD-MS has been used for
45、 the multi-elementsurvey analysis for these metals included in the scope of thisguide. Care must be taken in the interpretation of the results,however, due to the non-homogeneity of the sample surface.Reactive and refractory metals typically exhibit a relativelylarge grain size compared to the small
46、 area sampled by theconventional “pin” sample used by the GD-MS. It is alsopossible to sample a flat surface, which may help alleviate thegrain size problem. One should keep in mind that only a fewhundred micrograms of material are sampled, which under-scores the importance of homogeneity. Due to th
47、e high cost andcomplexity of the instrumentation, GD-MS is found in veryfew captive laboratories. Commercial analysis is availablethrough a limited number of laboratories.6.3.2 Glow Discharge Atomic Emission Spectrometry (GD-AES)The glow discharge excitation source is a device thatproduces luminous
48、plasma. Solid samples are sputtered usingthe low-pressure argon plasma. The argon ions etch atoms andsmall atomic clusters from the sample surface making themavailable for dissociation and excitation in the plasma. Metal-lurgical history is reduced because sampling and excitationtake place in separa
49、te locations. Calibration requires the use ofreference materials and where available it is possible todetermine the alloying and minor constituents simultaneously.6.4 X-ray Emission Spectrometry (XRF)See Guide E1621for details of the instrumentation. Again, the requirement for aset of homogeneous, solid reference materials limits the use ofthis technique. The low detection limit requirements for manyof the required elements in these materials will not be achievedby this technique. The analysis of iron, chromium, nickel, andtin in zirconium alloys and zirc
