1、BS EN ISO15351:2010ICS 77.080.01NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBRITISH STANDARDSteel and iron Determination ofnitrogen content Thermalconductimetric methodafter fusion in acurrent of inert gas(Routine method) (ISO15351:1999)This British Standardwas published un
2、der theauthority of the StandardsPolicy and StrategyCommittee on 31 May 2010 BSI 2010ISBN 978 0 580 69260 4Amendments/corrigenda issued since publicationDate CommentsBS EN ISO 15351:2010National forewordThis British Standard is the UK implementation of EN ISO 15351:2010.It is identical to ISO 15351:
3、1999.The UK participation in its preparation was entrusted to TechnicalCommittee ISE/18, Sampling and analysis of iron and steel.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not purport to include all the necessary provisionso
4、f a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunityfrom legal obligations.EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 15351 April 2010 ICS 77.080.01 English Version Steel and iron - Determination of nitrogen content -
5、 Thermal conductimetric method after fusion in a current of inert gas (Routine method) (ISO 15351:1999) Aciers et fontes - Dosage de lazote - Mthode par conductibilit thermique aprs fusion sous gaz inerte (Mthode pratique) (ISO 15351:1999) Stahl und Eisen - Bestimmung des Stickstoffgehaltes - Messun
6、g der Wrmeleitfhigkeit nach Aufschmelzen in strmendem Inertgas (Routineverfahren) (ISO 15351:1999)This European Standard was approved by CEN on 18 March 2010. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard th
7、e status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, Germ
8、an). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus
9、, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMI
10、T EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2010 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 15351:2010: EBS EN ISO 15351:2010EN ISO 15351:2010 (E) 3 Forewo
11、rd The text of ISO 15351:1999 has been prepared by Technical Committee ISO/TC 17 “Steel” of the International Organization for Standardization (ISO) and has been taken over as EN ISO 15351:2010 by Technical Committee ECISS/TC 102 “Methods of chemical analysis for iron and steel” the secretariat of w
12、hich is held by SIS. 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 October 2010, and conflicting national standards shall be withdrawn at the latest by October 2010. Attention is drawn to the po
13、ssibility 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 organizations of the following countries
14、 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, Romania, Slovakia, Slovenia,
15、 Spain, Sweden, Switzerland and the United Kingdom. Endorsement notice The text of ISO 15351:1999 has been approved by CEN as a EN ISO 15351:2010 without any modification. BS EN ISO 15351:2010ISO 15351:1999(E) ISO 1999 All rights reserved iiiContents Page1 Scope . .12 Normative references 13 Princip
16、le. .24 Reagents and materials 25 Apparatus .26 Sampling .37 Procedure . 38 Expression of results 59 Test report 6Annex A (informative) Features of commercial resistive electrode furnaces and nitrogen analysers 7Annex B (informative) Additional information on the international cooperative tests 9Ann
17、ex C (informative) Graphical representation of precision data .11BS EN ISO 15351:2010ISO 15351:1999(E)iv ISO 1999 All rights reservedForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISOmember bodies). The work of preparing Inter
18、national Standards is normally carried out through ISO technicalcommittees. Each member body interested in a subject for which a technical committee has been established hasthe right to be represented on that committee. International organizations, governmental and non-governmental, inliaison with I
19、SO, also take part in the work. ISO collaborates closely with the International ElectrotechnicalCommission (IEC) on all matters of electrotechnical standardization.International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3.Draft International Standards a
20、dopted by the technical committees are circulated to the member bodies for voting.Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote.Attention is drawn to the possibility that some of the elements of this International Standard may be the
21、subject ofpatent rights. ISO shall not be held responsible for identifying any or all such patent rights.International Standard ISO 15351 was prepared by Technical Committee ISO/TC 17, Steel, Subcommittee SC 1,Methods of determination of chemical composition.Annexes A, B and C of this International
22、Standard are for information only.BS EN ISO 15351:2010INTERNATIONAL STANDARD ISO 15351:1999(E) ISO 1999 All rights reserved 1SteelandironDeterminationofnitrogencontentThermalconductimetric method after fusion in a current of inert gas(Routine method)1 ScopeThis International Standard specifies a the
23、rmal conductimetric method after fusion under inert gas for thedetermination of nitrogen in steel and iron.The method is applicable to nitrogen contents between 0,002 % (m/m) and 0,6 % (m/m).2 Normative referencesThe following normative documents contain provisions which, through reference in this t
24、ext, constitute provisions ofthis International Standard. For dated references, subsequent amendments to, or revisions of, any of thesepublications do not apply. However, parties to agreements based on this International Standard are encouraged toinvestigate the possibility of applying the most rece
25、nt editions of the normative documents indicated below. Forundated references, the latest edition of the normative document referred to applies. Members of ISO and IECmaintain registers of currently valid International Standards.ISO Guide 31:1981, Contents of certificates of reference materials.ISO
26、Guide 35:1989, Certification of reference materials General and statistical principles.ISO 385-1:1984, Laboratory glassware Burettes Part 1: General requirements.ISO 648:1977, Laboratory glassware One-mark pipettes.ISO 1042:1998, Laboratory glassware One-mark volumetric flasks.ISO 3696:1987, Water f
27、or analytical laboratory use Specification and test methods.ISO 5725-1:1994, Accuracy (trueness and precision) of measurement methods and results Part 1: Generalprinciples and definitions.ISO 5725-2:1994, Accuracy (trueness and precision) of measurement methods and results Part 2: Basic methodfor th
28、e determination of repeatability and reproducibility of a standard measurement method.ISO 5725-3:1994, Accuracy (trueness and precision) of measurement methods and results Part 3: Intermediatemeasures of the precision of a standard measurement method.ISO 10702:1993, Steel and iron Determination of n
29、itrogen content Titrimetric method after distillation.ISO 10720:1997, Steel and iron Determination of nitrogen content Thermal conductimetric method afterfusion in a current of inert gas.ISO 14284:1996, Steel and iron Sampling and preparation of samples for the determination of chemicalcomposition.B
30、S EN ISO 15351:2010ISO 15351:1999(E)2 ISO 1999 All rights reserved3PrincipleFusion of a test portion in a single-use graphite crucible under helium gas at a high temperature (e.g. 2 200 Gb0C).Extraction of the nitrogen in the form of molecular nitrogen in the stream of helium.Separation from the oth
31、er gaseous extracts and measurement by thermal conductimetric method.Calibration graph established using steel or iron certified reference materials (CRM).NOTE The accuracy of the method is largely dependant upon the accuracy of the method used to certify the nitrogenconcentration of CRMs as well as
32、 upon their homogeneity. These calibration specimens shall be ECRM, NIST, JK, JSS, CMSIand other national or international CRMs.4 Reagents and materialsDuring the analysis, unless otherwise stated, use only reagents of recognized analytical grade and only grade 3water as specified in ISO 3696.4.1 Wa
33、ter, prepare just before use.4.2 Helium, high purity, total impurity content 0,000 5 % (m/m).An oxidation reagent or catalyst copper(II) oxide or platinum tube heated to a temperature above 450 Gb0C shall beused prior to a purifying unit, when the presence of organic contaminants is suspected in the
34、 helium.4.3 Copper (II) oxide, on granulated support.4.4 Magnesium perchlorate Mg (ClO4)2(commercial designation: anhydrone), particle size: from 1,2 mm to2 mm, or anhydrous calcium sulfate, (commercial designation: drierite), particle size from 0,6 mm to 0,85 mm.4.5 Sodium hydroxide, on granulated
35、support (commercial designation: ascarite), particle size: from 0,7 mm to1,2 mm.4.6 Appropriate solvent, suitable for washing greasy or dirty test samples, e.g. acetone.4.7 Steel or iron reference materials (RM), one or more of whose property values are sufficientlyhomogeneous as described in ISO Gu
36、ide 35 and well-established for use in the calibration of an apparatus, theassessment of a measurement method or for assigning values to materials.4.8 Steel or iron certified reference materials (CRM), steel or iron reference materials (4.7), accompanied bya certificate in accordance with ISO Guide
37、31 and one or more of whose chemical element concentrations havebeen established, in accordance with ISO Guide 35, by a referee method (e.g. ISO 10702 and 10720) whichestablishes its traceability to an accurate realization of the unit in which the property values are expressed, and forwhich each cer
38、tified value is accompanied by an uncertainty at a stated level of confidence.5 ApparatusDuring the analysis, unless otherwise stated, use only ordinary laboratory apparatus.All volumetric glassware shall be class A, in accordance with ISO 385-1, ISO 648 or ISO 1042 as appropriate.The apparatus requ
39、ired for fusion of the test portion and separation and measurement of the extracted nitrogenmay be obtained commercially from a number of manufacturers. Follow the manufacturers instructions for theoperation of the instrument.Features of commercial instruments are given in annex A.BS EN ISO 15351:20
40、10ISO 15351:1999(E) ISO 1999 All rights reserved 35.1 Graphite crucible, single-use.Use high purity crucibles suitable for use with the apparatus.5.2 Crucible tongs, for handling the crucibles used.5.3 Glass-wool filters.6 SamplingCarry out sampling in accordance with ISO 14284 or appropriate nation
41、al standards for steel and iron.7 ProcedureWARNING The risks involved when using an apparatus for fusing the test portion are mainly risks ofburns. It is therefore essential to use crucible tongs (5.2) and appropriate containers for the crucibles used.7.1 GeneralKeep the glass-wool filters (5.3) cle
42、an. Using a certified reference material, verify the effectiveness of the installedreagents (4.3, 4.4 and 4.5) and change them if necessary.In certain instruments, it is necessary to clean the sample introduction pipe in the furnace after each analysis inorder to eliminate carbon deposits. If the el
43、ectricity supply has been switched off for a long time, allow time for theinstrument to stabilize as recommended by the manufacturer.After changing the filters (5.3) and/or reagents (4.3, 4.4 and 4.5), or when the apparatus has been inoperative for aperiod, stabilize the instrument by carrying out t
44、rial analyses, the results of which are to be disregarded, thenproceed with calibration as indicated in 7.5 before analysing the sample.If the instrument used provides a direct reading in percentage of nitrogen, adjust the instrument reading for eachcalibration range as follows.Read the content of a
45、 certified reference material of high nitrogen content at various power settings. The requiredheating power for the determination of test samples is that at which the reading levels off.In order to determine a high alloy test sample a high alloy certified reference material shall be used to know the
46、required heating power.7.2 Test portionDegrease the test sample by washing in a suitable solvent (4.6). Evaporate the last traces of the washing liquid byheating.Weigh, to the nearest 1 mg, approximately 1 g of the test sample for nitrogen contents up to 0,1 % (m/m)andapproximately 0,5 g for nitroge
47、n contents greater than 0,1 % (m/m).NOTE The mass of the test portion may be dependent on the type of instrument used.7.3 Blank testPrior to the determination, carry out the following blank tests in duplicate.Place a graphite crucible (5.1) in the furnace (see annex A) and then degas by heating at a
48、 temperature greaterthan 2 200 Gb0C. Operate the furnace in accordance with the manufacturers instructions.BS EN ISO 15351:2010ISO 15351:1999(E)4 ISO 1999 All rights reservedObtain the reading of the blank tests and convert it to micrograms of nitrogen by means of the calibration graph(see 7.5).The
49、mean blank value (m1) is calculated from the two blank values.NOTE It is essential that neither the mean blank value nor the difference between the two blank values exceed 10 G6dgofnitrogen. If these values are abnormally high, the source of contamination should be investigated and eliminated.7.4 DeterminationPlace a graphite crucible (5.1) in the furnace (see annex A) and then degas by heating at a temperature greaterthan 2 200 Gb0C.Put the test portion (see 7.2) into the degassed graphite crucible.Operate the
