1、 g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58FAAS methodThe European Standard EN 14941:2006 has the status of a British StandardICS 77.120.30Cop
2、per and copper alloys Determination of cobalt content BRITISH STANDARDBS EN14941:2006BS EN 14941:2006This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 August 2006 BSI 2006ISBN 0 580 49066 1Cross-referencesThe British Standards which implemen
3、t international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online.This publication does no
4、t purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations.Summary of pagesThis document comprises a front cover, an inside front cover, the EN title
5、page, pages 2 to 12, an inside back cover and a back cover.The BSI copyright notice displayed in this document indicates when the document was last issued.Amendments issued since publicationAmd. No. Date CommentsA list of organizations represented on this committee can be obtained on request to its
6、secretary. present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep UK interests informed; monitor related international and European developments and promulgate them in the UK.National forewordThis British Standard is the off
7、icial English language version of EN 14941:2006. The UK participation in its preparation was entrusted to Technical Committee NFE/34, Copper and copper alloys, which has the responsibility to: aid enquirers to understand the text;EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 14941June 2006ICS 77
8、.120.30English VersionCopper and copper alloys - Determination of cobalt content -FAAS methodCuivre et alliages de cuivre - Dosage du cobalt - Mthodepar spectromtrie dabsorption atomique dans la flamme(SAAF)Kupfer und Kupferlegierungen - Bestimmung desCobaltgehaltes -Flammenatomabsorptionsspektromet
9、risches Verfahren(FAAS)This European Standard was approved by CEN on 15 May 2006.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bi
10、bliographical references concerning such nationalstandards may be obtained on application to the Central Secretariat or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of
11、 a CEN member into its own language and notified to the Central Secretariat has the same status as the officialversions.CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latv
12、ia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania,Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels
13、2006 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 14941:2006: EEN 14941:2006 (E) 2 Contents Page Foreword3 1 Scope 4 2 Normative references 4 3 Principle4 4 Reagents and Materials.4 5 Apparatus .5 6 Sampling.5 7 Procedure .5 8 Exp
14、ression of results 9 9 Precision.10 10 Test report 11 Bibliography12 EN 14941:2006 (E) 3 Foreword This document (EN 14941:2006) has been prepared by Technical Committee CEN/TC 133 “Copper and copper al-loys”, the secretariat of which is held by DIN. This European Standard shall be given the status o
15、f a national standard, either by publication of an identical text or by endorsement, at the latest by December 2006, and conflicting national standards shall be withdrawn at the latest by December 2006 Within its programme of work, Technical Committee CEN/TC 133 requested CEN/TC 133/WG 10 “Methods o
16、f analysis“ to prepare the following standard: EN 14941, Copper and copper alloys Determination of cobalt content FAAS method According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following coun-tries are bound to implement this European Standard: Austria, Be
17、lgium, Cyprus, Czech Republic, Denmark, Esto-nia, 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. EN 14941:2006 (E) 4 1 Scope T
18、his European Standard specifies a flame atomic absorption spectrometric method (FAAS) for the determination of the cobalt content of copper and copper alloys in the form of unwrought, wrought and cast products. The method is applicable to products having cobalt mass fractions between 0,010 % and 3,0
19、 %. 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, Copper and
20、 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 NOTE Informative references to docum
21、ents used in the preparation of this standard, and cited at the appropriate places in the text, are listed in the Bibliography. 3 Principle Dissolution of a test portion in hydrochloric-nitric acid mixture followed, after suitable dilution, by aspiration into an air/acetylene flame of an atomic abso
22、rption spectrometer. Measurement of the absorption of the 240,7 nm line emitted by a cobalt hollow-cathode lamp. 4 Reagents and Materials 4.1 General During the analysis, use only reagents of recognized analytical grade and only distilled water or water of equivalent purity. 4.2 Hydrochloric acid, H
23、Cl ( = 1,19 g/ml). 4.3 Nitric acid, HNO3( = 1,40 g/ml). 4.4 Nitric acid solution, 1 + 1 Dilute 100 ml of nitric acid (4.3), in 100 ml of water. 4.5 Cobalt stock solution, 1,000 g/l Co Weigh (1 0,001) g of cobalt (Co 99,9 %) and transfer it into a 250 ml beaker. Add 20 ml of nitric acid solution (4.4
24、), cover and heat gently until the cobalt is completely dissolved. Boil the solution for a few minutes to expel ni-trous fumes. Cool to room temperature, 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
25、contains 1,000 mg of Co. EN 14941:2006 (E) 5 4.6 Cobalt standard solution, 0,100 g/l Co Using a pipette, transfer 25,0 ml of cobalt stock solution (4.5) into a 250 ml one-mark volumetric flask. Dilute to the mark with water and mix well. Prepare the solution immediately prior to use. 1 ml of this so
26、lution contains 0,100 mg of Co. 4.7 Lanthanum(III) chloride solution (100 g/l) Dissolve 100 g of lanthanum(III) chloride (LaCl3 7H2O) in a 600 ml beaker with water and transfer the solution quantitatively into a 1 000 ml one-mark volumetric flask. Dilute to the mark with water and mix well. 4.8 Copp
27、er base solution, 20 g/l Cu Weigh 10,0 g cobalt-free copper (Co 0,000 2 %) and transfer it into a 600 ml beaker. Add 200 ml of hydrochloric acid (4.2) and, cautiously, 200 ml of nitric acid solution (4.4). Heat until the copper is dissolved and then boil until nitrous fumes have been expelled. Cool
28、to room temperature and transfer the solution quantitatively into a 500 ml one-mark volumetric flask, dilute to the mark with water and mix well. 5 Apparatus 5.1 Ordinary laboratory apparatus. 5.2 Atomic absorption spectrometer, fitted with an air/acetylene burner. 5.3 Cobalt hollow-cathode lamp. 6
29、Sampling Sampling shall be carried out in accordance with ISO 1811-1 or ISO 1811-2, as 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
30、 of the test sample. 7.1.2 Test portion solution Transfer the test portion (7.1.1) into a 250 ml beaker and cover with a watch glass. Add 20 ml of hydrochloric acid (4.2) and 20 ml of nitric acid solution (4.4). Heat gently until the test portion is completely dissolved, then continue heating to the
31、 boiling point until the nitrous fumes have been expelled. Wash the cover and the sides of the beaker with water and allow to cool. Transfer the solution to a 100 ml one-mark volumetric flask, add 10 ml of lantha-num(III) chloride solution (4.7), dilute to the mark with water and mix well. Select an
32、 aliquot portion from the test portion solution according to the expected cobalt mass fraction and prepare a dilution in a volumetric flask as indicated in Table 1. Add lanthanum(III) chloride solution as shown in Table 1. EN 14941:2006 (E) 6 Table 1 Dilution Aliquot of Lanthanum(III)- Final volume
33、Cobalt mass the test portion chloride of diluted Dilution fractions solution solution solution factor (7.1.2) (4.7) Dr% ml ml ml 0,01 to 0,2 100 0 100 1 0,1 to 1,0 20 8 100 5 0,5 to 3,0 20 48 500 5a 5baaFor explanation of dilution factors see the notes to Clause 8 Expression of results. 7.2 Blank te
34、st Carry out a blank test 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 standard mat
35、erial or a synthetic sample containing a known amount of cobalt and of composition similar to the material to be analysed. Carry out the pro-cedure specified in 7.5. 7.4 Establishment of the calibration curve 7.4.1 Preparation of the calibration solutions 7.4.1.1 General In all cases, copper, chlori
36、de and nitrate concentrations and acidity in the calibration solutions shall be similar to those of the test portion solutions. The presence of copper in the standard calibration solutions compensates for chemical interaction effects of copper in the test portion solution. Normally no similar additi
37、ons are required to compensate for the 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 Co concentration of the calibration solutions shall be adju
38、sted to suit the sensitivity of the apparatus used, so that the curve of absorbance as a function of the concentration is a straight line. 7.4.1.2 Calibration range for cobalt mass fractions between 0,01 % and 3,0 % Into each of a series of eight 100 ml one-mark volumetric flasks, introduce the volu
39、mes of cobalt standard solution (4.6) and of copper base solution (4.8) shown in Tables 2, 3 or 4, depending on the expected cobalt content. Intro-duce also, 10 ml of lanthanum(III) chloride solution (4.7). Dilute to the mark with water and mix well. EN 14941:2006 (E) 7 Table 2 Calibration for cobal
40、t mass fractions between 0,01 % and 0,20 % Cobalt Corresponding Corresponding Copper Corresponding Corresponding standard cobalt cobalt base copper cobalt solution volume mass concentration after solution volume mass mass fraction (4.6) final dilution (4.8) of sample ml mg mg/ml ml g % 0a0 0 50 1,00
41、0 0 1 0,1 0,001 50 1,000 0,01 2 0,2 0,002 50 1,000 0,02 5 0,5 0,005 50 1,000 0,05 7 0,7 0,007 50 1,000 0,07 10 1,0 0,010 50 1,000 0,10 15 1,5 0,015 50 1,000 0,15 20 2,0 0,020 50 1,000 0,20 aBlank test on reagents for calibration curve. Table 3 Calibration for cobalt mass fractions between 0,05 % and
42、 1,0 % Cobalt Corresponding Corresponding Copper Corresponding Corresponding standard cobalt cobalt base copper cobalt solution volume mass concentration after solution volume mass mass fraction (4.6) final dilution (4.8) of sample ml mg mg/ml ml g % 0a0 0 10 0,200 0 1 0,1 0,001 10 0,200 0,05 2 0,2
43、0,002 10 0,200 0,10 5 0,5 0,005 10 0,200 0,25 7 0,7 0,007 10 0,200 0,35 10 1,0 0,010 10 0,200 0,50 15 1,5 0,015 10 0,200 0,75 20 2,0 0,020 10 0,200 1,00 aBlank test on reagents for calibration curve. EN 14941:2006 (E) 8 Table 4 Calibration for cobalt mass fractions between 0,25 % and 3,0 % Cobalt Co
44、rresponding Corresponding Copper Corresponding Corresponding standard cobalt cobalt base copper cobalt solution volume mass concentration solution volume mass mass (4.6) after (4.8) fraction final dilution of sample ml mg mg/ml ml g % 0a0 0 2 0,040 0 1 0,1 0,001 2 0,040 0,25 2 0,2 0,002 2 0,040 0,50
45、 5 0,5 0,005 2 0,040 1,25 7 0,7 0,007 2 0,040 1,75 10 1,0 0,010 2 0,040 2,50 11 1,1 0,011 2 0,040 2,75 12 1,2 0,012 2 0,040 3,00 aBlank test on reagents for calibration curve. 7.4.2 Adjustment of the atomic absorption spectrometer Fit the cobalt hollow-cathode lamp (5.3) into the atomic absorption s
46、pectrometer, switch on the current and allow to stabilize. Adjust the wavelength in the region of 240,7 nm to minimum absorbance. Following the manufacturers instructions, fit the correct burner, light the flame and allow the burner temperature to stabilize. Taking careful note of the manufacturers
47、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 absorbance. 7.4.3 Spectrometric measurement of the calibration solutions Aspirate the relevant series o
48、f calibration solutions (see Tables 2, 3 or 4 depending on the expected cobalt 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 graph. Spray water through the burner after each meas
49、urement. 7.4.4 Calibration curve Establish the calibration curve using measured absorbances and corresponding analyte amounts. Use appropriate spectrometer software or off-line computer for regression calculations or prepare a graphical representation. 7.5 Determination 7.5.1 General The analyses shall be carried out independently, in duplicate. 7.5.2 Preliminary spectrometric measurement Carry out a preliminary measurement on the test portion solution (7.1.2) following the same procedure s
