1、BS EN ISO21068-1:2008ICS 81.080NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBRITISH STANDARDChemical analysisof silicon-carbide-containing rawmaterials andrefractory productsPart 1: General information andsample preparation (ISO 21068-1:2008)This British Standardwas publishe
2、d under theauthority of the StandardsPolicy and StrategyCommittee on 32008 BSI 2008ISBN 978 0 580 58091 8Amendments/corrigenda issued since publicationDate CommentsBS EN ISO 21068-1:2008National forewordThis British Standard is the UK implementation of EN ISO21068-1:2008.The UK participation in its
3、preparation was entrusted to TechnicalCommittee RPI/1, Refractory products and materials.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 provisionsof a contract. Users are responsible for
4、its correct application.Compliance with a British Standard cannot confer immunityfrom legal obligations.0 SeptemberEUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN ISO 21068-1August 2008ICS 81.080English VersionChemical analysis of silicon-carbide-containing raw materialsand refractory products - P
5、art 1: General information and samplepreparation (ISO 21068-1:2008)Analyse chimique des matires premires et des produitsrfractaires contenant du carbure de silicium - Partie 1:Informations gnrales et prparation des chantillons (ISO21068-1:2008)Chemische Analyse von Siliciumcarbid enthaltendenRohstof
6、fen und feuerfesten Erzeugnissen - Teil 1:Allgemeine Angaben und Probenvorbereitung (ISO 21068-1:2008)This European Standard was approved by CEN on 11 July 2008.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard t
7、he status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards 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, Germa
8、n). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Repub
9、lic, 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 STANDARDIZATIONCOMIT EUROPEN DE NORM
10、ALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2008 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN ISO 21068-1:2008: EBS EN ISO 21068-1:2008EN ISO 21068-1:2008 (E) 3 Foreword This docum
11、ent (EN ISO 21068-1:2008) has been prepared by Technical Committee ISO/TC 33 “Refractories“ in collaboration with Technical Committee CEN/TC 187 “Refractory products and materials” the secretariat of which is held by BSI. This European Standard shall be given the status of a national standard, eithe
12、r by publication of an identical text or by endorsement, at the latest by February 2009, and conflicting national standards shall be withdrawn at the latest by February 2009. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and
13、/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 are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republi
14、c, 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 the United Kingdom. Endorsement notice The text of ISO 21068-1:2008 has be
15、en approved by CEN as a EN ISO 21068-1:2008 without any modification. BS EN ISO 21068-1:2008ISO 21068-1:2008(E) ISO 2008 All rights reserved iiiContents Page Foreword iv Introduction.v 1 Scope1 2 Normative references3 3 Definitions 3 4 Sampling and preparation of the test sample 4 4.1 General .4 4.2
16、 Sample pretreatment.4 5 Preliminary analyses.5 6 Expression of results6 7 Test report6 Bibliography7 BS EN ISO 21068-1:2008ISO 21068-1:2008(E) iv ISO 2008 All rights reservedForeword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO
17、 member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, gover
18、nmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC D
19、irectives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted 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
20、bodies casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 21068-1 was prepared by Technical Committee ISO/TC 33, Refractories ISO 21
21、068 consists of the following parts, under the general title Chemical analysis of silicon-carbide-containing raw materials and refractory products: Part 1: General information and sample preparation Part 2: Determination of loss on ignition, total carbon, free carbon and silicon carbide, total and f
22、ree silica and total and free silicon Part 3: Determination of nitrogen, oxygen and metallic and oxidic constituents BS EN ISO 21068-1:2008ISO 21068-1:2008(E) ISO 2008 All rights reserved vIntroduction ISO 21068, Parts 1 to 3, have been developed from the combination of a Japanese standard JIS 2011
23、2and work items originally developed within CEN. As there is a wide variety of laboratory equipment in use, the most commonly used methods are described. ISO 21068, Parts 1 to 3, are applicable to the analysis of all refractory products as classified in ISO 10081 10 to 13(shaped) and ISO 1927 3(unsh
24、aped) and raw materials containing carbon and/or silicon carbide. Therefore, ISO 21068, Parts 1 to 3, covers the full range of analysis from pure silicon carbide to oxidic refractory composition with low-content silicon carbide and/or nitrides. Primarily, ISO 21068, Parts 1 to 3, provides methods to
25、 distinguish between different carbon bound types like total carbon (Ctotal) and free carbon (Cfree) and derives from these two the silicon carbide content. If free carbon is present, the standard includes different types of temperature treatment in order to determine the mass changes gravimetricall
26、y. Frequently, the resulting residue is used for other determinations. The determination of other groups of analytes described in ISO 21068, Parts 1 to 3, are free metals, free silicon (Sifree), free aluminum (Alfree), free magnesium (Mgfree), free iron (Fefree) and the group of oxides from main to
27、trace components. ISO 21068, Parts 1 to 3, also describe the chemical analysis of silicon dioxide, total silicon, oxygen and nitrogen and other oxidic bound metals that typically occur in the materials. It represents a listing of analytical methods which is approximately structured according to mate
28、rial composition. However, it is still the user who should prove the applicability of the method depending on the material and analytical requirements. The most broadly used analytical techniques such as X-ray fluorescence spectroscopy (XRF) and inductively coupled plasma-optical emission spectromet
29、ry (ICP-OES) suffer from the disadvantage that the analytical results are chemical bond independent. For carbon-containing ceramic raw materials and compositions ISO 21068, Parts 1 to 3, provide analytical methods for the determination of free carbon, and SiC in the presence of oxidic compounds in p
30、articular SiO2. Because of the diversity of laboratory equipment, the three parts of ISO 21068 summarize broadly used analytical techniques which lead to equivalent results. In principle, the determination of carbon is based in all itemized methods on the oxygen extraction method, where carbon is ox
31、idized at elevated temperatures. Thereafter carbon is analysed as CO2. As well as carbon and carbidic compounds, metallic silicon, aluminium and magnesium are considered. While metallic silicon is in majority a precursor material which remains after the production process of SiC in the raw material,
32、 metallic aluminium is added as an antioxidant in carbon-containing refractory formulations. Mostly oxidic bound components, such as Al2O3, CaO, MgO, TiO2, Cr2O3, ZrO2and alkalines, can be determined by XRF as described in ISO 12677, ICP-AES or wet chemical methods (see ISO 26845 25, ISO 21587-1 22a
33、nd ISO 21587-3 24). These results can be corrected by formulas provided by ISO 21068, Parts 1 to 3, in consideration of the values obtained by the determination of carbon, SiC, and metallic components. ISO 21068, Parts 1 to 3, also provide methods for qualitative and quantitative determinations of t
34、he nitrogen content and the determination of oxygen. Thereby only the total content of nitrogen and oxygen is given; a precise determination of non-carbide components (oxides and nitrides) is not possible in this way. ISO 21068, Parts 1 to 3, do not provide methods to distinguish quantitatively betw
35、een different varieties of nitrides like silicon nitride, silicon oxy-nitride and sialon. For further information about the determination of this group of compounds, see EN 12698-2. BS EN ISO 21068-1:2008BS EN ISO 21068-1:2008INTERNATIONAL STANDARD ISO 21068-1:2008(E) ISO 2008 All rights reserved 1C
36、hemical analysis of silicon-carbide-containing raw materials and refractory products Part 1: General information and sample preparation 1 Scope This part of ISO 21068 gives definitions and specifies techniques for the preparation of samples for the chemical analysis of silicon-carbide-containing raw
37、 materials and refractory products including: a) graphite brick containing silicon carbide; b) silicon carbide brick (includes the bricks containing silicon nitride); c) refractories containing carbon and/or silicon carbide mixed with clay; d) refractories containing carbon and/or silicon carbide mi
38、xed with silica (and fused silica); e) refractories containing carbon and/or silicon carbide mixed with high alumina material; f) refractories containing carbon and/or silicon carbide mixed with magnesia (and dolomite); g) refractories containing carbon and/or silicon carbide mixed with chrome miner
39、al or magnesia-chrome materials; h) refractories containing carbon and/or silicon carbide except those described in a) to g) above. The items of chemical analysis described in ISO 21068, Parts 1 to 3 are as follows: 1) loss on drying (LOD); 2) loss on ignition (LOI); 3) total carbon, Ctotal; 4) free
40、 carbon, Cfree; 5) silicon carbide, SiC; 6) free silicon (Sifree); 7) free aluminium (Alfree); 8) free magnesium (Mgfree); 9) free iron (Fefree); 10) silicon(IV) oxide (SiO2); BS EN ISO 21068-1:2008ISO 21068-1:2008(E) 2 ISO 2008 All rights reserved11) aluminium oxide (Al2O3); 12) iron(III) oxide (to
41、tal iron oxide calculated as Fe2O3); 13) titanium(IV) oxide (TiO2); 14) calcium oxide (CaO); 15) magnesium oxide (MgO); 16) sodium oxide (Na2O); 17) potassium oxide (K2O); 18) chromium(III) oxide (Cr2O3); 19) zirconium oxide (ZrO2); 20) boron oxide (total boron calculated as B2O3); 21) nitrogen; 22)
42、 oxygen; 23) nitrides (undifferentiated: Si3N4, AlN, BN, sialon, oxy-nitrides, etc.). The range of determination specified in this part of ISO 21068 is given in Table 1. Table 1 Range of determination Component Range % by mass LOI 10 to 99 Ctotal0,01 to 99 Cfree0,01 to 99 SiC 3 to 99 Sifree0,1 to 10
43、 Alfree0,1 to 10 Mgfree0,1 to 10 Fefree0,1 to 10 SiO20,1 to 95 Al2O30,1 to 95 Fe2O30,1 to 15 TiO20,1 to 5 CaO 0,1 to 60 MgO 0,1 to 95 Na2O 0,1 to 5 K2O 0,1 to Cr2O30,1 to 40 ZrO20,1 to 1 B2O30,1 to 5 Si3N40,1 to 35 BS EN ISO 21068-1:2008ISO 21068-1:2008(E) ISO 2008 All rights reserved 32 Normative r
44、eferences The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 31-0, Quantities and units Part 0:
45、General principles ISO 5022, Shaped refractory products Sampling and acceptance testing ISO 8656-1, Refractory products Sampling of raw materials and unshaped products Part 1: Sampling scheme ISO 12677:2003, Chemical analysis of refractory products by XRF Fused cast bead method EN 12698-2, Chemical
46、analysis of nitride bonded silicon carbide refractories Part 2: XRD methods ISO 21068-2:2008, Chemical analysis of silicon-carbide-containing raw materials and refractory products Part 2: Determination of loss on ignition, total carbon, free carbon and silicon carbide, total and free silica and tota
47、l and free silicon 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 unshaped refractory materials mixtures consisting of an aggregate and a bond or bonds, prepared ready for use either directly in the condition in which they are supplied or af
48、ter the addition of one or more suitable liquids NOTE 1 Unshaped refractory materials can contain metallic, organic or ceramic fibre material. NOTE 2 These mixtures are either dense or insulating. Insulating mixtures are those whose true porosity is not less than 45 % when determined in accordance w
49、ith EN 1094-41using a test piece fired to specified conditions. 3.2 dense shaped refractory materials preshaped and burned or tempered refractory compositions to obtain a ceramic or a carbon-based bond NOTE Dense shaped refractory materials are classified in accordance with ISO 1008110 to 13. 3.3 moisture water which is not chemically bound in refractory raw materials and products, from moisture absorption during storage, or residual water used for the preparation of a refractory castable mix 3.4 volatile com
