1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN 15025:2010Copper and copper alloys Determination of magnesiumcontent Flame atomicabsorption spectrometricmethod (FAAS)BS EN 15025:2010 BRITISH STANDARDNational forewordThis
2、 British Standard is the UK implementation of EN 15025:2010. Itsupersedes DD CEN/TS 15025:2006 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee NFE/34, Copper and copper alloys.A list of organizations represented on this committee can beobtained on reque
3、st to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. BSI 2010ISBN 978 0 580 66408 3ICS 77.120.30Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standa
4、rd was published under the authority of theStandards Policy and Strategy Committee on 31 August 2010Amendments issued since publicationDate Text affectedBS EN 15025:2010EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 15025 July 2010 ICS 77.120.30 Supersedes CEN/TS 15025:2006English Version Copp
5、er and copper alloys - Determination of magnesium content - Flame atomic absorption spectrometric method (FAAS) Cuivre et alliages de cuivre - Dtermination du magnsium - Mthode par spectromtrie dabsorption atomique dans la flamme (SAAF) Kupfer und Kupferlegierungen - Bestimmung des Magnesiumgehaltes
6、 - Flammenatomabsorptionsspektrometrisches Verfahren (FAAS) This European Standard was approved by CEN on 19 June 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
7、 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, German). A version in any other language ma
8、de 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, Czech Republic, Denmark, Estonia, Fin
9、land, 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 COMIT EUROPEN DE NORMALISATION EUROPISCHES
10、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 15025:2010: EBS EN 15025:2010EN 15025:2010 (E) 2 Contents Page Foreword 31 Scope 42 Normative references 4
11、3 Principle 44 Reagents .45 Apparatus .56 Sampling .57 Procedure .57.1 Preparation of the test portion solution 57.1.1 Test portion 57.1.2 Test portion solution .57.2 Blank test 67.3 Check test .67.4 Preparation of the calibration curve 67.4.1 Preparation of the calibration solutions 67.4.2 Adjustme
12、nt of the atomic absorption spectrometer 77.4.3 Spectrometric measurement of the calibration solutions .87.4.4 Calibration curve87.5 Determination .87.5.1 General 87.5.2 Preliminary spectrometric measurement 87.5.3 Spectrometric measurements 88 Expression of results 88.1 Use of calibration curve 88.
13、2 Use of bracketing method .99 Precision .910 Test report . 10Bibliography . 12BS EN 15025:2010EN 15025:2010 (E) 3 Foreword This document (EN 15025:2010) has been prepared by Technical Committee CEN/TC 133 “Copper and copper alloys”, the secretariat of which is held by DIN. This European Standard sh
14、all be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by January 2011, and conflicting national standards shall be withdrawn at the latest by January 2011. Attention is drawn to the possibility that some of the elements of this do
15、cument may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes CEN/TS 15025:2006. Within its programme of work, Technical Committee CEN/TC 133 requested CEN/TC 133/WG 10 “Methods of analysis“ to pre
16、pare the revision of the following document: CEN/TS 15025:2006, Copper and copper alloys Determination of magnesium content Flame atomic absorption spectrometry method (FAAS). In comparison with the first edition of CEN/TS 15025:2006, the following significant technical changes were made: Transforma
17、tion into a European Standard; In 7.4.1.1, text added; Clause 9, Precision - completely revised. 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, Croatia, Cypr
18、us, 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. BS EN 15025:2010EN 15025:2010 (E) 4 1
19、 Scope This European Standard specifies a flame atomic absorption spectrometric method (FAAS) for the determination of magnesium content of copper and copper alloys in the form of unwrought, wrought and cast products. The method is applicable to products having magnesium mass fractions between 0,001
20、 % and 0,20 %. 2 Normative references 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 1811-1,
21、 Copper and copper alloys Selection and preparation of samples for chemical analysis Part 1: Sampling of cast unwrought products ISO 1811-2, Copper and copper alloys Selection and preparation of samples for chemical analysis Part 2: Sampling of wrought products and castings 3 Principle Dissolution o
22、f a test portion in a hydrochloric-nitric acid mixture followed, after suitable dilution, by aspiration into an air/acetylene flame of an atomic absorption spectrometer. Determination of the magnesium content by measuring the absorption of the 285,2 nm line emitted by a magnesium hollow-cathode lamp
23、. 4 Reagents During the analysis, use only reagents of recognized analytical grade and only distilled water or water of equivalent purity. 4.1 Hydrochloric acid, HCl ( = 1,19 g/ml). 4.2 Nitric acid, HNO3( = 1,40 g/ml). 4.3 Nitric acid solution, 1 + 1. Add 100 ml of nitric acid (4.2) to 100 ml of wat
24、er. 4.4 Magnesium stock solution, 0,5 g/l Mg. Weigh (0,5 0,001) g of magnesium (Mg 99,9 %) and transfer it into a 250 ml beaker. Add 20 ml of the nitric acid solution (4.3) in small amounts. Cover with a watch glass and heat gently until the magnesium is completely dissolved. Boil the solution until
25、 nitrous fumes have been expelled. Cool to room temperature and transfer the solution quantitatively into a 1 000 ml one-mark volumetric flask. Dilute to the mark with water and mix well. 1 ml of this solution contains 0,5 mg of Mg. 4.5 Magnesium standard solution, 0,01 g/l Mg. Transfer 5 ml of the
26、magnesium stock solution (4.4) into a 250 ml one-mark volumetric flask. Dilute to the mark with water and mix well. BS EN 15025:2010EN 15025:2010 (E) 5 Prepare this solution immediately prior to use. 1 ml of this solution contains 0,01 mg of Mg. 4.6 Magnesium standard solution, 0,000 5 g/l Mg. Trans
27、fer 5 ml of the magnesium standard solution (4.5) into a 100 ml one-mark volumetric flask. Dilute to the mark with water and mix well. Prepare this solution immediately prior to use. 1 ml of this solution contains 0,000 5 mg of Mg. 4.7 Lanthanum (III) chloride solution, 200 g/l. Dissolve 100 g of la
28、nthanum chloride heptahydrate (LaCl37H2O) in a 1 000 ml beaker with approximately 400 ml of water. Transfer the solution into a 500 ml one-mark volumetric flask. Dilute to the mark with water and mix well. 4.8 Copper base solution, 10 g/l Cu. Weigh (10 0,01) g of electrolytic copper and transfer it
29、into a 1 000 ml beaker. Add 100 ml of hydrochloric acid (4.1) and, in small amounts, 100 ml of the nitric acid solution (4.3). Cover with a watch glass and heat gently until the copper is dissolved, then boil until the nitrous fumes have been expelled. Cool to room temperature and transfer the solut
30、ion into a 1 000 ml one-mark volumetric flask. Dilute to the mark with water and mix well. 5 Apparatus 5.1 Atomic absorption spectrometer, fitted with an air/acetylene burner. 5.2 Magnesium hollow-cathode lamp. 6 Sampling Sampling shall be carried out in accordance with ISO 1811-1 or ISO 1811-2, as
31、appropriate. Test samples shall be in the form of fine drillings, chips or millings, with a maximum thickness of 0,5 mm. 7 Procedure 7.1 Preparation of the test portion solution 7.1.1 Test portion Weigh (1 0,001) g of the test sample. 7.1.2 Test portion solution Transfer the test portion (7.1.1) int
32、o a 250 ml beaker. Add 10 ml of hydrochloric acid (4.1) and 10 ml of the nitric acid solution (4.3). Cover with a watch glass and heat gently until the test portion is completely dissolved, then heat at a temperature of approximately 90 C until nitrous fumes have been expelled. Cool to room temperat
33、ure. Wash the cover and the sides of the beaker with water. Transfer the solution to a 100 ml one-mark volumetric flask. Dilute to the mark with water and mix well. BS EN 15025:2010EN 15025:2010 (E) 6 Select an aliquot portion from the test portion solution according to the expected magnesium mass f
34、raction as indicated in Table 1. Table 1 Aliquot solution Magnesium (mass fraction) Aliquot of the test portion solution (7.1.2) Lanthanum (III) chloride solution volume (4.7) Final volume of diluted solution % ml ml ml0,001 to 0,05 10 10 100 0,05 to 0,2 5 10 100 7.2 Blank test Carry out a blank tes
35、t simultaneously with the determination, following the same procedure and using the same quantities of all reagents as used for the determination, but omitting the test portion. 7.3 Check test Make a preliminary check of the apparatus by preparing a solution of a reference material or a synthetic sa
36、mple containing a known amount of magnesium and of a composition similar to the material to be analysed. Carry out the procedure specified in 7.5. 7.4 Preparation of the calibration curve 7.4.1 Preparation of the calibration solutions 7.4.1.1 General In all cases, copper, chloride and nitrate concen
37、trations, and acidity in the calibration solutions shall be similar to those of the test portion solutions. The presence of copper in the calibration solutions compensates for chemical interaction effects of copper in the test solution. Normally no similar additions are required to compensate for th
38、e effect of alloying elements. If an alloying element is present in the material to be analysed in mass fraction 10 %, an appropriate mass of this element shall be added to the calibration solutions. The volumes of copper base solution added (4.8) have been calculated to compensate for chemical inte
39、raction effects of copper in test solutions of copper or high-copper alloys. Overcompensation may occur if the same volumes are added when the test samples are copper-based alloys where the percentage of copper is lower. In these cases the volumes of copper base solution shall be decreased to match
40、the copper content of the test sample in solution. The magnesium concentration of the calibration solutions shall be adjusted to suit the sensitivity of the spectrometer used, so that the curve of absorbance as a function of concentration is a straight line. 7.4.1.2 Magnesium mass fractions between
41、0,001 % and 0,20 % Into each of a series of 100 ml one-mark volumetric flasks, introduce the volumes of magnesium standard solution (4.5 or 4.6) and of copper base solution (4.8) shown in Tables 2 or 3, depending on the expected magnesium content, followed by 10 ml of lanthanum (III) chloride soluti
42、on (4.7). Dilute to the mark with water and mix well. The range of calibration solutions is appropriate for most current models of equipment of average performance. The range and operating conditions shall be selected for optimum measurements by the particular equipment available. BS EN 15025:2010EN
43、 15025:2010 (E) 7 Table 2 Calibration for magnesium mass fractions between 0,001 % and 0,05 % Magnesium standard solution volume Corresponding magnesium mass Correspondingmagnesium concentration after final dilution Copper base solution volumeCorresponding copper mass Correspondingmagnesium mass fra
44、ctionof sample (4.6) (4.5) (4.8) ml ml mg mg/ml ml g % 0a 0 0 10 0,1 0 2 0,001 0,000 01 10 0,1 0,001 4 0,002 0,000 02 10 0,1 0,002 10 0,005 0,000 05 10 0,1 0,005 20 0,01 0,000 1 10 0,1 0,010 2 0,02 0,000 2 10 0,1 0,020 3 0,03 0,000 3 10 0,1 0,030 4 0,04 0,000 4 10 0,1 0,040 5 0,05 0,000 5 10 0,1 0,0
45、50 aBlank test on reagents for calibration curve. Table 3 Calibration for magnesium mass fractions between 0,05 % and 0,20 % Magnesium standard solution volume (4.5) Corresponding magnesium mass Correspondingmagnesium concentration after final dilution Copper base solution volume(4.8) Corresponding
46、copper mass Correspondingmagnesium mass fractionof sample ml mg mg/ml ml g % 0a0 0 5 0,050 0 2,5 0,025 0,000 25 5 0,050 0,05 5,0 0,050 0,000 50 5 0,050 0,10 7,5 0,075 0,000 75 5 0,050 0,15 10,0 0,1 0,001 5 0,050 0,20 aBlank test on reagents for calibration curve. 7.4.2 Adjustment of the atomic absor
47、ption spectrometer Fit the magnesium hollow-cathode lamp (5.2) into the atomic absorption spectrometer (5.1), switch on the current and allow it to stabilize. Adjust the wavelength in the region of 285,2 nm to minimum absorbance. Following the manufacturers instructions, fit the correct burner, ligh
48、t the flame and allow the burner temperature to stabilize. Taking careful note of the manufacturers instructions regarding the minimum flow rate of acetylene, aspirate the calibration solution of highest concentration of analyte and adjust the burner configuration and gas flows to obtain maximum abs
49、orbance. BS EN 15025:2010EN 15025:2010 (E) 8 7.4.3 Spectrometric measurement of the calibration solutions Aspirate the relevant series of calibration solutions (Tables 2 or 3 depending on the expected magnesium content) in succession into the flame and measure the absorbance for each. Take care to keep the aspiration rate constant throughout the preparation of the calibration curve. Spray water through the burne
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