1、June 2008DEUTSCHE NORM English price group 9No part of this standard 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).ICS 81.060.30!$O+g“1440868www.
2、din.deDDIN EN 725-1Advanced technical ceramics Methods of test for ceramic powders Part 1: Determination of impurities in aluminaEnglish version of DIN EN 725-1:2008-06Hochleistungskeramik Prfverfahren fr keramische Pulver Teil 1: Bestimmung von Verunreinigungen in AluminiumoxidpulverEnglische Fassu
3、ng DIN EN 725-1:2008-06SupersedesDIN EN 725-1:2007-11www.beuth.deDocument comprises 13 pagesDIN EN 725-1:2008-06 2 National foreword This standard has been prepared by Technical Committee CEN/TC 184 “Advanced technical ceramics” (Secretariat: BSI, United Kingdom). At present a DIN committee does not
4、 exist for this standard since the parties concerned have not shown any interest in work on the subject. The Normenausschuss Materialprfung (Materials Testing Standards Committee) is obliged to publish the standard, however, as the subject falls in its domain. Amendments This standard differs from D
5、IN EN 725-1:1997-06 as follows: a) Clause 2 “Normative references” has been revised and updated. b) Subclause 4.2 “Reagents for fusion”, subclause 4.3 “Sulphuric acid-phosphoric acid mixture for acid dissolution” and subclause 4.4 “Reagents for calibration” have been extensively revised. c) The list
6、 of apparatus in clause 5 has been revised and extended. d) The test report in clause 12 has been extended. Compared with DIN EN 725-1:2007-11, corrections have been made to the German version only and therefore do not affect the English text. Previous editions DIN EN 725-1: 1997-06, 2007-11 EUROPEA
7、N STANDARDNORME EUROPENNEEUROPISCHE NORMEN 725-1September 2007ICS 81.060.30 Supersedes EN 725-1:1997 English VersionAdvanced technical ceramics - Methods of test for ceramicpowders - Part 1: Determination of impurities in aluminaCramiques techniques avances - Mthodes dessai desdans lalumineHochleist
8、ungskeramik - Prfverfahren fr keramischePulver - Teil 1: Bestimmung von Verunreinigungen inAluminiumoxidpulverThis European Standard was approved by CEN on 11 August 2007.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
9、Standard the 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, Fre
10、nch, German). 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, C
11、zech 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 STANDARDIZATIONCOMIT EUROP
12、EN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2007 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 725-1:2007: Epoudres cramiques - Partie 1: Dosage des impuretsEN 725-1:2007
13、(E) 2 Contents Page Foreword3 1 Scope 4 2 Normative references 4 3 Principle4 4 Reagents.4 4.1 General4 4.2 Reagents for fusion .4 4.3 Sulphuric acid-phosphoric acid mixture for acid dissolution 5 4.4 Reagents for calibration5 5 Apparatus .5 6 Test sample 5 7 Decomposition of the test sample .6 7.1
14、General6 7.2 Fusion .6 7.3 Acid dissolution.6 8 Calibration graph .6 8.1 General6 8.2 Fusion .6 8.3 Acid dissolution.7 8.4 Drawing the calibration curve 7 9 Adjustment of the apparatus7 9.1 Atomic absorption spectrometer .7 9.2 Inductively coupled plasma spectrometer8 10 Measurements8 11 Expression
15、of the results8 12 Test report 9 Bibliography 11 DIN EN 725-1:2008-06 Annex A (informative) Repeatability and reproducibility 10 EN 725-1:2007 (E) 3 Foreword This document (EN 725-1:2007) has been prepared by Technical Committee CEN/TC 184 “Advanced technical ceramics”, the secretariat of which is h
16、eld 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 March 2008, and conflicting national standards shall be withdrawn at the latest by March 2008. This document supersedes EN 725-1:1997. E
17、N 725 Advanced technical ceramics Methods of test for ceramic powders was prepared in parts as follows: Part 1: Determination of impurities in alumina Part 2: Determination of impurities in barium titanate Part 3: Determination of the oxygen content of non-oxides by thermal extraction with a carrier
18、 gas Part 4: Determination of oxygen content in aluminium nitride by XRF analysis Part 5 Determination of particle size distribution Part 6: Determination of the specific surface area withdrawn Part 7: Determination of the absolute density withdrawn Part 8: Determination of tapped bulk density Part
19、9: Determination of un-tapped bulk density Part 10: Determination of compaction properties Part 11: Determination of densification on natural sintering Part 12: Chemical analysis of zirconia Parts 6 and 7 of the series were superseded in 2005 by EN ISO 18757 and EN ISO 18753 respectively. According
20、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 Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Li
21、thuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. DIN EN 725-1:2008-06 EN 725-1:2007 (E) 4 1 Scope This Part of EN 725 specifies one fusion and one acid dissolution method for the determination of elements o
22、f sodium, potassium, iron, silicon, calcium and magnesium present as impurities in alumina using atomic absorption spectroscopy (AAS) or inductively coupled plasma (ICP) spectroscopy. For each element present as impurities, the methods are applicable to the following ranges, calculated as oxides : S
23、odium oxide: 20 ppm to 6000 ppm Potassium oxide: 20 ppm to 100 ppm Ferric oxide: 20 ppm to 300 ppm Silica: 50 ppm to 2000 ppm Calcium oxide: 20 ppm to 700 ppm Magnesium oxide: 5 ppm to 1000 ppm 2 Normative references The following referenced documents are indispensable for the application of this do
24、cument. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN ISO 3696, Water for analytical laboratory use - Specification and test methods (ISO 3696:1987) EN ISO/IEC 17025, General requirem
25、ents for the competence of testing and calibration laboratories (ISO/IEC 17025:2005) 3 Principle A test sample is decomposed by using either a fusion method or an acid dissolution method. NOTE The acid dissolution method cannot be used for the determination of silicon. The solution is transferred to
26、 a volumetric flask and diluted to a known volume, and the elements are determined by AAS or ICP. 4 Reagents 4.1 General During the analysis, use only reagents and calibration solutions of at least 99,99 % purity and water conforming to EN ISO 3696, Grade 3, or better. 4.2 Reagents for fusion 4.2.1
27、Lithium metaborate - LiBO24.2.2 Nitric acid HNO3- (20= 1,33 g/ml) DIN EN 725-1:2008-06 EN 725-1:2007 (E) 5 4.3 Sulphuric acid-phosphoric acid mixture for acid dissolution Pour 700 ml of phosphoric acid (20= 1,78 g/ml) into 300 ml of sulphuric acid (20= 1,84 g/ml). 4.4 Reagents for calibration 4.4.1
28、Pure alumina, of very low and known impurity levels, 99,99% purity. 4.4.2 Sodium - commercial solution or solution obtained by dissolution of pure chemical compound, of concentration 1 g/l. 4.4.3 Potassium - commercial solution or solution obtained by dissolution of pure chemical compound, of concen
29、tration 1 g/l. 4.4.4 Iron (ferric) - commercial solution or solution obtained by dissolution of pure chemical compound, of concentration 1 g/l. 4.4.5 Silicon - commercial solution or solution obtained by dissolution of pure chemical compound, of concentration 1 g/l. 4.4.6 Calcium - commercial soluti
30、on or solution obtained by dissolution of pure chemical compound, of concentration 1 g/l. 4.4.7 Magnesium - commercial solution or solution obtained by dissolution of pure chemical compound, of concentration 1 g/l. 5 Apparatus 5.1 Platinum or platinum-gold crucible with a capacity of at least 50 ml
31、5.2 Muffle furnace, suitable for operation in the range of (1 000 50) C to (1 200 50) C 5.3 Hot plate with magnetic stirrer 5.4 Atomic absorption spectrometer and/or inductively coupled plasma spectrometer 5.5 Laboratory glassware 5.6 Platinum spatula 6 Test sample Use samples of approximately: 1 g
32、for decomposition by fusion; 1 g for decomposition by acid dissolution. Weigh them to 0,0001 g. DIN EN 725-1:2008-06 EN 725-1:2007 (E) 6 7 Decomposition of the test sample 7.1 General Dissolve either by a fusion method (see 7.2) or an acid dissolution method (see 7.3) 7.2 Fusion Weigh 4 g of LiBO2(4
33、.2.1) and 1 g of test sample into a platinum or platinum-gold crucible (5.1). Mix intimately using a platinum spatula, put on lid. Place the crucible and contents into the muffle furnace (5.2) maintained at 1150 C 50 C for 30 min (after the first 15 min, swirl the contents of the crucible for a few
34、seconds and put back in the muffle). Remove the crucible from the furnace, remove lid and rinse with distilled water, pouring the residue into a 400 ml beaker containing 80 ml of water and 20 ml of nitric acid (4.2.2). Dip its base in water at ambient temperature (this procedure allows easy removal
35、of the bead from the crucible). To prevent sticking of melt in the crucible, either use a new crucible or, with an old one, immerse it in the solution. Pour the bead, carefully, into the 400 ml beaker that contains 80 ml of water and 20 ml of nitric acid (4.2.2). Place the beaker, covered with a wat
36、ch glass on a hot plate (5.3) with magnetic stirring and maintain the agitation at approximately 80 C 10 C until complete dissolution. Remove the beaker from the stirrer and allow it to cool down. Transfer the solution quantitatively into a 200 ml volumetric flask. Allow it to cool down to room temp
37、erature and make up to the mark. 7.3 Acid dissolution Weigh the test sample (see Clause 6) into a platinum or gold-platinum crucible (5.1). Add carefully 12 ml of sulphuric acid-phosphoric acid mixture (4.3) and cover with a lid. Put the crucible with the lid on to the hot plate (5.3) and maintain i
38、t at boiling for 12 min. Remove the crucible from the heating device and allow it to cool down. Transfer the content quantitatively into a 100 ml volumetric flask which contains 30 ml of water. Rinse the crucible and the lid with distilled water into the flask and after cooling, make up to the mark
39、with water. 8 Calibration graph 8.1 General The optimum calibration graph is obtained using calibration solutions whose concentrations are compatible both with the analytical method (AAS or ICP) and with the impurity concentrations in the sample, and matrix matched. The following procedure is given
40、as an example. 8.2 Fusion Prepare five decompositions of pure alumina (4.4.1) in accordance with 7.2. Transfer into five 200 ml volumetric flasks and dilute to 150 ml with water. Add the quantities of solutions indicated in Table 1. Make up to the mark with water. DIN EN 725-1:2008-06 EN 725-1:2007
41、(E) 7 Table 1 Quantities of solutions for fusion Elements 1 2 3 4 5 Na 0 l 1 l 2 l 4 l 6 l K 0 l 100 l 200 l 300 l 400 l Ca 0 l 250 l 500 l 750 l 1000 l Fe 0 l 100 l 200 l 300 l 400 l Si 0 l 200 l 400 l 800 l 1600 l Mg 0 l 250 l 500 l 750 l 1000 l 8.3 Acid dissolution Prepare 5 dissolutions of pure
42、alumina (4.4.1) in accordance with 7.3. Transfer into five 100 ml volumetric flasks and dilute to 50 ml with water. Add the quantities indicated in Table 2. Make up to the mark with water. Table 2 Quantities of solutions for acid dissolution Elements 1 2 3 4 5 Na 0 l 500 l 1000 l 2000 l 3000 l K 0 l
43、 50 l 100 l 150 l 200 l Ca 0 l 125 l 250 l 375 l 500 l Fe 0 l 50 l 100 l 150 l 200 l Mg 0 l 125 l 250 l 375 l 1000 l 8.4 Drawing the calibration curve 8.4.1 Blank test Prepare a blank test in accordance with 8.2 or 8.3 using the same quantities of all reagents as for dissolution of the test sample,
44、but using pure alumina (4.4.1) in place of the test sample. 8.4.2 Drawing the calibration curve Draw a graph of the AAS or ICP intensities recorded using the calibration solutions prepared against the impurity concentrations. 9 Adjustment of the apparatus 9.1 Atomic absorption spectrometer Follow th
45、e manufacturers instructions for igniting and extinguishing the nitrous oxide-acetylene flame to avoid explosion, and ensure the safety screen is in place. Set the wavelengths for the elements to be analysed (see Table 3) and adjust the apparatus so as to obtain maximum absorbance. Fit the correct b
46、urner and, in accordance with the manufacturers instructions, light the DIN EN 725-1:2008-06 EN 725-1:2007 (E) 8 flame. After 10 min preheating of the burner, adjust fuel and burner to obtain maximum absorbance while aspirating the highest calibration solution. Aspirate water and set to give the zer
47、o absorbance. Aspirate the blank solution and then, alternately aspirate the calibration solutions and water to establish that the absorbance reading is not drifting and draw the calibration graph. 9.2 Inductively coupled plasma spectrometer Follow the manufacturers instructions for igniting the pla
48、sma. Ensure the safety screen is in place. NOTE 1 The wavelengths in Table 3 can be used for the analysis. Depending on the analytical method and element concentration, other wavelengths can also be used. NOTE 2 It should be ensured that there is no spectral interference if other lines are used. Wai
49、t until a stable signal is obtained. It is possible to use an internal standard to improve the precision of the results. NOTE 3 It is usual to use yttrium as the internal standard. Table 3 Recommended wavelengths for analysis Elements Atomic absorption (recommendations) ICP (recommendations) Na 589,0 nm 589,0 nm K 766,5 nm 769,9 nm Ca 422,7 nm 393,3 nm Fe 248,3 nm 259,9 nm Si 251,6 nm 251,6 nm Mg 285,2 nm 279,5 nm 10 Measurements Aspirate the blank a
