1、February 2010 Translation by DIN-Sprachendienst.English price group 6No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).IC
2、S 77.160!$Gs“1573680www.din.deDDIN EN ISO 3908Hardmetals Determination of insoluble (free) carbon Gravimetric method (ISO 3908:2009)English translation of DIN EN ISO 3908:2010-02Hartmetalle Bestimmung des unlslichen (freien) Kohlenstoff-Gehaltes Gravimetrisches Verfahren (ISO 3908:2009)Englische ber
3、setzung von DIN EN ISO 3908:2010-02Mtaux-durs Dosage du carbone insoluble (libre) Mthode gravimtrique (ISO 3908:2009)Traduction anglaise de DIN EN ISO 3908:2010-02SupersedesDIN ISO 3908:1991-07www.beuth.deIn case of doubt, the German-language original shall be considered authoritative.Document compr
4、ises 9 pages02.10 DIN EN ISO 3908:2010-02 2 National foreword This standard has been prepared by Technical Committee ISO/TC 119 “Powder metallurgy” (Secretariat: SIS, Sweden) in collaboration with Technical Committee CEN/SS M11 “Powder metallurgy” (Secretariat: CMC). The responsible German body invo
5、lved in its preparation was the Normenausschuss Werkstofftechnologie (Technology of Materials Standards Committee), Working Committee NA 145-01-04 AA Probenahme und Prfverfahren fr Hartmetalle. The DIN Standard corresponding to the International Standard referred to in this document is as follows: I
6、SO 3907:2009 DIN EN ISO 3907:2010-02 Amendments This standard differs from DIN ISO 3908:1991-07 as follows: a) The standard has been editorially revised. b) In the German version, the national footnote has been deleted. Previous editions DIN ISO 3908: 1991-07 National Annex NA (informative) Bibliogr
7、aphy DIN EN ISO 3907:2010-02, Hardmetals Determination of total carbon content Gravimetric method SO 3907:2009(I ) A comma is used as the decimal marker. EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 3908 October 2009 ICS 77.160 Supersedes EN 23908:1993English Version Hardmetals - Determi
8、nation of insoluble (free) carbon - Gravimetric method (ISO 3908:2009) Mtaux-durs - Dosage du carbone insoluble (libre) - Mthode gravimtrique (ISO 3908:2009) Hartmetalle - Bestimmung des unlslichen (freien) Kohlenstoffgehaltes - Gravimetrisches Verfahren (ISO 3908:2009) This European Standard was ap
9、proved by CEN on 29 September 2009. 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 concerning such nat
10、ional 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, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and
11、 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, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembour
12、g, 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-1000 Brussels 2009 CEN All rights o
13、f exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 3908:2009: E2 DIN EN ISO 3908:2010-02 EN ISO 3908:2009 (E) Contents Page Foreword 3 1 Scope4 2 Normative references4 3 Principle .4 4 Reagents 4 5 Apparatus.5 6 Sampling 5 7 Procedure.5 7.1 Test
14、portion5 7.2 Attack5 7.3 Preparation of the Gooch crucible 5 7.4 Filtering.6 7.5 Blank test .6 7.6 Determination 6 8 Expression of results6 8.1 Calculation .6 8.2 Tolerances6 8.3 Final result .7 9 Test report7 Foreword 3 This European Standard shall be given the status of a national standard, either
15、 by publication of an identical text or by endorsement, at the latest by April 2010, and conflicting national standards shall be withdrawn at the latest by April 2010. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CEN
16、ELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes EN 23908:1993. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium
17、, Bulgaria, Cyprus, 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 the United Kingdom. Endorsement notice Th
18、e text of ISO 3908:2009 has been approved by CEN as a EN ISO 3908:2009 without any modification. metallurgy”. This document (EN ISO 3908:2009) has been prepared by Technical Committee ISO/TC 119 “Powder EN ISO 3908:2009 (E) DIN EN ISO 3908:2010-02 1 Scope This International Standard specifies a grav
19、imetric method for the determination of the mass fraction of insoluble (free) carbon in carbides and hardmetals. This method is applicable to carbides of hafnium, molybdenum, niobium, tantalum, titanium, vanadium, tungsten and zirconium, mixtures of these carbides and binder metals, free of lubrican
20、t, and all grades of presintered or sintered hardmetals, produced from these carbides, having a mass fraction of insoluble carbon between 0,02 % and 0,5 %. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the
21、 edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 3907:2009, Hardmetals Determination of total carbon Gravimetric method 3 Principle Decomposition of the carbides and determination of the insoluble carbon by a gravim
22、etric method. 4 Reagents During the analysis, use only reagents of recognized analytical grade, and only distilled water or water of equivalent purity. 4.1 Nitric acid, = 1,20 g/ml. Add 2 000 ml of nitric acid, = 1,42 g/ml, to 3 000 ml of water. 4.2 Hydrofluoric acid, = 1,12 g/ml. 4 DIN EN ISO 3908:
23、2010-02 EN ISO 3908:2009 (E) 5 Apparatus Ordinary laboratory apparatus and the following. 5.1 Apparatus, as specified in ISO 3907. 5.2 Platinum dish, of capacity 200 ml. 5.3 Filter device: ceramic filter device or bed of suitable refractory fibrous or powder material in a Gooch crucible. NOTE If nec
24、essary, pretreat the refractory material at 800 C to 1 000 C under strongly oxidizing conditions for a minimum of 3 h. If pretreated, store it in a desiccator. 5.4 Vacuum filtration assembly. 6 Sampling 6.1 The sample shall be crushed to a powder in a mortar made of a material which does not alter t
25、he sample composition. The powder shall pass through a 180 m sieve. 6.2 The analysis shall be carried out on two or three test portions. 7 Procedure 7.1 Test portion Weigh, to the nearest 0,01 g, approximately 2,5 g of the test sample. 7.2 Attack Transfer the test portion (7.1) into the platinum dis
26、h (5.2). Add 75 ml of the nitric acid (4.1) and place the dish on a steam bath for 5 min. Add, drop by drop, 10 ml of the hydrofluoric acid (4.2), and leave the dish on the steam bath for about 1 h until complete dissolution is obtained. Cool the solution to ambient temperature. CAUTION Hydrofluoric
27、 and nitric acids are very dangerous chemicals. Any contact with these acids or inhalation of their vapours shall be avoided. All operations with these acids shall be carried out in a fume-cupboard with good ventilation. 7.3 Preparation of the Gooch crucible Insert the ceramic filter device (5.3) in
28、to the crucible. If a refractory material is used, fill the crucible to a depth of approximately 8 mm to 10 mm and press it down so that the residue will be retained on the refractory material and the time of filtering will not be too slow. 5 EN ISO 3908:2009 (E) DIN EN ISO 3908:2010-02 7.4 Filterin
29、g Before filtering, add a limited quantity of water to avoid the precipitation of tungstic acid. Filter the contents of the dish (see 7.2) through the filter device (5.3). Then rinse the dish twice with small volumes of water. Be sure that all particles of carbon are transferred to the filter device
30、. Rinse the dish again with water at least twice and then wash the filter device free from acid with hot water (about 500 ml is usually needed). Remove the wet filter device from the Gooch crucible and transfer the wet filter device into a boat (see ISO 3907:2009, 4.1.5). Dry it at 110 C. 7.5 Blank
31、test Carry out two blank tests for each series of determinations. Prepare the Gooch crucible in accordance with 7.3. Filter through the filter device (5.3) a mixture of 75 ml of the nitric acid (4.1) and 10 ml of the hydrofluoric acid (4.2) and proceed in accordance with 7.4. 7.6 Determination Burn
32、the filter device (5.3) in a stream of oxygen in accordance with ISO 3907. Use a furnace with an inner temperature of the tube of approximately 1 200 C. 8 Expression of results 8.1 Calculation The mass fraction of carbon , expressed as a percentage, is given by the formula 21027,29mmm where m0is the
33、 mass, in grams (g), of the test portion; m1is the mass, in grams (g), of carbon dioxide obtained from the blank test; m2is the mass, in grams (g), of carbon dioxide obtained from the combustion of the test portion; 27,29 is the carbon dioxide to carbon conversion factor, multiplied by 100. 8.2 Tole
34、rances The deviation between two or three independent determinations shall not exceed the values shown in Table 1. Table 1 Tolerances Total carbon mass fraction Range for two determinations Range for three determinations % % % from 0,02 to 0,1 0,02 0,03 over 0,1 to 0,5 0,04 0,05 6 DIN EN ISO 3908:20
35、10-02 EN ISO 3908:2009 (E) 8.3 Final result Report the arithmetical mean of acceptable determinations rounded to the nearest 0,01 % (mass fraction). 9 Test report The test report shall include the following information: a) a reference to this International Standard; b) all details necessary for the identification of the test sample; c) the result obtained; d) all operations not specified in this International Standard, or regarded as optional; e) details of any occurrence which may have affected the result. 7 EN ISO 3908:2009 (E) DIN EN ISO 3908:2010-02
