1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN 15991:2011Testing of ceramic andbasic materials Directdetermination of massfractions of impurities inpowders and granules ofsilicon carbide by inductivelycoupled plasma opt
2、icalemission spectrometry (ICPOES) with electrothermalvaporisation (ETV)Copyright European Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN 15991:2011 BRITISH STANDARDNational forewordThis Bri
3、tish Standard is the UK implementation of EN 15991:2011.The UK participation in its preparation was entrusted to TechnicalCommittee RPI/1, Refractory products and materials.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purp
4、ort to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. BSI 2011ISBN 978 0 580 64180 0ICS 81.060.10Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandar
5、ds Policy and Strategy Committee on 28 February 2011.Amendments issued since publicationDate Text affectedCopyright European Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN 15991:2011EUROPEAN
6、 STANDARD NORME EUROPENNE EUROPISCHE NORM EN 15991 January 2011 ICS 81.060.10 English Version Testing of ceramic and basic materials - Direct determination of mass fractions of impurities in powders and granules of silicon carbide by inductively coupled plasma optical emission spectrometry (ICP OES)
7、 with electrothermal vaporisation (ETV)Essais sur matriaux cramiques et basiques - Dtermination directe des fractions massiques dimpurets dans les poudres et les granuls de carbure de silicium par spectroscopie dmission optique plasma induit par haute frquence (ICP OES) avec vaporisation lectrotherm
8、ique (ETV) Prfung keramischer Roh- und Werkstoffe - Direkte Bestimmung der Massenanteile von Spurenverunreinigungen in pulver- und kornfrmigem Siliciumcarbid mittels optischer Emissionsspektrometrie mit induktiv gekoppeltem Plasma (ICP OES) und elektrothermischer Verdampfung (ETV) This European Stan
9、dard was approved by CEN on 10 December 2010. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concernin
10、g such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into it
11、s own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland,
12、Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-
13、1000 Brussels 2011 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 15991:2011: ECopyright European Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without li
14、cense from IHS-,-,-BS EN 15991:2011EN 15991:2011 (E) 2 Contents Page Foreword 31 Scope 42 Principle 43 Spectrometry 44 Apparatus .65 Reagents and auxiliary material .76 Sampling and sample preparation .77 Calibration 78 Procedure .89 Wavelength and working range 910 Calculation of the results and ev
15、aluation .911 Reporting of results .912 Precision 1013 Test report . 10Annex A (informative) Results of interlaboratory study . 11Annex B (informative) Wavelength and working range 16Annex C (informative) Possible interferences and their elimination 18Annex D (informative) Information regarding the
16、evaluation of the uncertainty of the mean value . 21Annex E (informative) Commercial certified reference materials . 22Annex F (informative) Information regarding the validation of an analytical method based on liquid standards at the example of SiC and graphite 23Bibliography . 26Copyright European
17、 Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN 15991:2011EN 15991:2011 (E) 3 Foreword This document (EN 15991:2011) has been prepared by Technical Committee CEN/TC 187 “Refractory products
18、and materials”, the secretariat of which is held by BSI. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by July 2011, and conflicting national standards shall be withdrawn at the latest by July 2011
19、. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. According to the CEN/CENELEC Internal Regulations, the national standards organizati
20、ons of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal
21、, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Copyright European Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN 15991:2011EN 15991:2011 (E) 4 1 Scope This
22、 European Standard defines a method for the determination of the trace element concentrations of Al, Ca, Cr, Cu, Fe, Mg, Ni, Ti, V and Zr in powdered and granular silicon carbide. Dependent on element, wavelength, plasma conditions and weight, this test method is applicable for mass contents of the
23、above trace contaminations from about 0,1 mg/kg to about 1 000 mg/kg, after evaluation also from 0,001 mg/kg to about 5 000 mg/kg. NOTE 1 Generally for optical emission spectrometry using inductively coupled plasma (ICP OES) and electrothermal vaporisation (ETV) there is a linear working range of up
24、 to four orders of magnitude. This range can be expanded for the respective elements by variation of the weight or by choosing lines with different sensitivity. After adequate verification, the standard is also applicable to further metallic elements (excepting Rb and Cs) and some non-metallic conta
25、minations (like P and S) and other allied non-metallic powdered or granular materials like carbides, nitrides, graphite, soot, coke, coal, and some other oxidic materials (see 1, 4, 5, 6, 7, 8, 9 and 10). NOTE 2 There is positive experience with materials like for example graphite, B4C, Si3N4, BN an
26、d several metal oxides as well as with the determination of P and S in some of these materials. 2 Principle The sample material, crushed if necessary, is evaporated in an argon- carrier-gas stream in a graphite boat in the graphite tube furnace of the ETV unit. The evaporation products containing th
27、e element traces are transported as a dry aerosol into the plasma of the ICP-torch and there excited for the emission of optical radiation. In a simultaneous emission spectrometer in, for example Paschen-Runge- or Echelle-configuration, the optical radiation is dispersed. The intensities of suited s
28、pectral lines or background positions are registered with applicable detectors like photomultipliers (PMT), charge coupled devices (CCD), charge injection devices (CID), and serial coupled devices (SCD). By comparison of the intensities of the element-specific spectral lines of the sample with calib
29、ration samples of known composition, the mass fractions of the sample elements are determined. 3 Spectrometry Optical emission spectrometry is based on the generation of line spectra of excited atoms or ions, where each spectral line is associated with an element and the line intensities are proport
30、ional to the mass fractions of the elements in the analysed sample. In contrary to the wet chemical analysis from dilution in ICP OES the classical sample digestion is replaced by electrothermal vaporisation at high temperatures in a graphite furnace. By a suitable design of the furnace (see Figures
31、 1 and 2) and a suited gas regime in the transition area graphite tube / transport tube (see Figure 1), it is ensured that the sample vapour is carried over into a form that is to transport effectively (see 5, 6, 7, 8, 10). Carbide forming elements, for example titanium, zirconium, that are not or i
32、ncompletely evaporating need a suited modifier, like a halogenation agent, preferably dichlorodifluoromethane, to be converted into a form that is easy to transport (see 1, 3, 5 and 10.) The dry aerosol is introduced into the ICP plasma by the injector tube and there excited for the emission of ligh
33、t (see Figures 1 to 3). Copyright European Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN 15991:2011EN 15991:2011 (E) 5 Key 1 graphite tube with boat and sample 5 bypass gas (Ar) 2 carrier g
34、as (Ar) 6 aerosol 3 reaction gas (Freon) 7 to the ICP torch 4 shield gas (Ar) Figure 1 Schematic configuration of the ETV-gas regime with the gas flows carrier-gas, bypass-gas and shield-gas Key 1 graphite tube furnace 6 bypass-gas (Ar) 2 pyrometer 7 aerosol 3 carrier gas (Ar) + reaction gas 8 trans
35、port tube 4 solid sample 9 ICP-torch 5 vapour 10 power supply 0 A to 400 A Figure 2 Schematic design of the ETV-ICP-combination with an axial plasma (example) Copyright European Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted
36、without license from IHS-,-,-BS EN 15991:2011EN 15991:2011 (E) 6 Key 1 Al2O3-transport tube 5 carrier gas evaporated sample 2 Al2O3-transition ring 6 bypass gas 3 nozzle 7 gas mixture in laminar flow 4 graphite tube Figure 3 Schematic configuration of the transition area between graphite- and transp
37、ort-tube NOTE Figures 1 to 3 show a well established commercial instrument. 4 Apparatus 4.1 Common laboratory instruments according to 4.2 to 4.7. 4.2 ICP-emission spectrometer, simultaneous, preferably with the possibility to register transient emission signals and suited for the synchronised start
38、 of ETV vaporisation cycle and signal registration. NOTE Especially for changing matrices the measurement of the spectral background near the analysis lines is beneficial, because by this the systematic and stochastic contributions of the analysis uncertainty can be decreased, the latter only by sim
39、ultaneous measurement of the background. The use of spectrometers equipped with Echelle or similar CID systems are an advantage in such cases as they allow a simultaneous background measurement, in addition to their possibility to save a lot of time in the analysis cycle. 4.3 Electrothermal vaporisa
40、tion system with graphite furnace with suited transition zone graphite tube / transport tube for optimised aerosol formation, to be connected to the injector tube of the ICP torch by a transport tube for example made of corundum, PTFE, PFA, PVC (cross-linked), with controlled gas flows (preferably w
41、ith mass-flow-control) and furnace control (preferably with continuous online-temperature measurement of the graphite boat connected to a feed forward control of the power supply) for a reproducible control of the temperature development. 4.4 Tweezers, self-closing, made of a material preventing con
42、tamination. 4.5 Micro spatula, made of a material preventing contamination. 4.6 Microbalance, capable of reading to the nearest 0,01 mg. NOTE A microbalance with a direct reading of 0,001 mg is advantageous. 4.7 Mill or crusher, free of contamination, for example mortar made of a material that does
43、not contaminate the sample with any of the analytes to be determined. Copyright European Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN 15991:2011EN 15991:2011 (E) 7 5 Reagents and auxiliary
44、 material Only analytical grade reagents shall be used unless stated otherwise. 5.1 Sample boats of graphite (spectral grade) adapted in size to the graphite tube of the ETV, baked out for the necessary purity. 5.2 Calibration samples with well-defined mass fractions of trace-impurities, preferably
45、certified reference materials (CRM). NOTE For silicon nitride, silicon carbide and boron carbide certified reference material is available for main-, minor- and trace-components. (For CRMs, see Annex E.) 5.3 Calibration solutions, made of tested stock solutions of the elements to be analysed. 5.4 Mo
46、difier, halogenation agents, for example in form of halocarbons, preferably dichlorodifluoromethane. NOTE Dichlordiflouromethane is the most effective modifier, some alternative modifiers have serious disadvantages. According to the EU-regulation (see 12) of materials influencing the ozone layer, th
47、is chemical product is allowed for laboratory use and for the use as a starting substance. 5.5 Argon purity 99,99 % (volume fraction). 6 Sampling and sample preparation Sampling has to be performed in a way that the sample to be analysed is representative for the total amount of material, using for
48、example ISO 5022 13, ISO 8656-1 14, EN ISO 21068-1 15, but this list is not exhaustive. If the sample is not received in a dry state, it shall be dried at (110 10) C until constant mass is achieved ( 0,5 % variation). The sample is then cooled down to room temperature and stored in a desiccator. NOTE Drying for 2 h is normally sufficient. It is critical that the sample material is on hand at a particle size of 50 m; eventually it has to be broken up and homogenised, if necessary. For this a crushing device suit
