1、5 - -i a c 5 E ? C . c c * C U 1: - c 2 c I C u E c f f 2 i t ? a 2 E 2 4 C I 4 c C 7 L c (1 u c - f I c a z Q EN comprises 8 pages. BeutH Verlag-Grnhw, BBrlrcr, he the+excluS!de right oflsale forGerman Standards (DIN-Normen). DilM EN 24-W ER. WwQrO,dp 7 03.93 SS NU. in07 UDC E9iI : 543,422 : 54B.56
2、 Fareward On the proposaCofiTMTIicall(=ommita;ee TC 20, the Caordinating Gomrnissioa (C:cieOR) of the Eiumpean Cmmritteefrrr lmni a.md Stee+lSfandandizatian (EG1SS)dkided in Nowember 19E6 to submit Ihbrnatimal StWrdlirrd IS0 4943: 19853 Steel arrdfczst rom- De-tiermiiaidian of+ mppw contant- Rme-ato
3、mio abszorptiani spermatricrmthdi Ya FormaliVote. This Europeani Standard was appnoxell by GM ani 1989-1 11-27. Irraacardancie with tiheGENKENELEG Internal Rqulatians, tiheflIawinlgicourrtPiieJE 8663- bmnd to implemmt this European1 Sttandad: Austria, Belgjsirn, Denmark, Findand, Frarrca, Germany.,
4、Greece: Ikel$nd. lrel dwlitzeriarrdiarrdf United Kingdbm. Page 3, EN 24 943: 19901 4.4- COPEJF,. sd. use wly fitcshty prepared di 713.2.1 and O;= $6 fm%rn$ CUJ in the.amzofi7.32.2 Type af i dl makeare tbattk liquid, trapisfilled wirhlwatmn Set- the abwikm valus at zem using the zero rnemtrer (X3,2.1
5、1 cw 7.3i2.21. Evabate the criieria o% 5.11.1 ta 5mre tirati the instrumem is; suirzblk fun the determinaiticm. Se3 the =la expameion COI *ab the colibjton s0lutrei-r af kigffiesj conmtratiam gives near at =ci% iwl. where B)i ths results, arrd the fiscm in which thyare acpr- 1- UDC 669.13/.14 : 620.
6、1 : 543.422 : 546.56 DEUTSCHE NORM October 1992 Determination of copper content of steel and cast iron by flame atomic absorption spectrometry (IS0 4943 : 1985) English version of DIN EN 24 943 DIN - EN 24 943 This standard incorporates the English version of Is0 4943. Stahl und Gueisen; Bestimmung
7、des Kupfergehalts; flammenatomabsorptionsspektrometrisches Verfahren (IS0 4943 : 1985) European Standard EN 24 943 : 1990 has the status of a DIN Standard. A comma is used as the decimal marker. National foreword This standard has been prepared by ECISSTTC 20. The responsible German body involved in
8、 the preparation of this standard was the Normenausschu Eisen und Stahl (Steel and Iron Standards Committee). Standards referred to See References. EN comprises 8 pages. Eeuth Verlag GmbH, Berlin, has the exciusive right of sale for German Standards (DIN-Normen). DIN EN 24 943 Engi. Price group 7 03
9、.93 Sales No. 11 07 EUROPEAN STANDARD EN 24943 NORME EUROPENNE EUROPAISCHE NORM March 1990 UDC 669.1 : 543.422 : 546.56 Descriptors: Steel, cast iron, chemical analysis, determination of copper content, atomic absorption spectrophotometry, flame photometry. English version Steel and cast iron Determ
10、ination of copper content Flame atomic absorption spectrometric method (IS0 4943 : 1985) Aciers et fontes; dosage de cuivre; mthode par spectromtrie dabsorption Stahl und Gueisen; Bestimmung des Kupfergehalts; flammenatomabsorp- atomique dans la flamme (IS0 4943 : 1985) tionsspektrometrisches Verfah
11、ren (IS0 4943 : 1985) This European Standard was approved by CEN on 1989-1 1-27 and is identical to the IS0 Standard as referred to. CEN members are bound to comply with the CENKENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national stan
12、dard without any alteration. Up-to-date lists and bibliographical references concerning such national standards 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). Aversion in any other la
13、nguage made by translation under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Irela
14、nd, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassatt 36, B-1050 Brussels O 1990. Copyright reserved to all CEN
15、 members. Ref. No. EN 24 943 : 1990 E Page 2 EN 24 943 : 1990 Foreword On the proposal of Technical Committee TC 20, the Coordinating Commission (COCOR) of the European Committee for Iron and Steel Standardization (ECISS) decided in November 1986 to submit International Standard IS0 4943 : 1985 Stee
16、l and cast iron - Determination of copper content - Flame atomic absorption spectrometric method to Formal Vote. This European Standard was approved by CEN on 1989-11-27. In accordance with the CENKENELEC Internal Regulations, the following countries are bound to implement this European Standard: Au
17、stria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. Endorsement notice The text of International Standard IS0 4943 : 1985 was approved by CEN as a European Standard without any m
18、odification. Page 3 EN 24 943 : 1990 1 Scope and field of application This International Standard specifies a method for the deter- mination of copper in steel and cast iron by means of flame atomic absorption spectrometry. The method is applicable to copper contents in the range 0,004 to 0,5 % (m/m
19、). 4.3 Hydrochloric acid-nitric acid-perchloric acid mixture. Mix 20 ml of hydrochloric acid (e about 1,19 g/ml) with 55 ml of nitric acid (e about 1,40 g/ml) and 75 ml of perchloric acid (e about 1,54 g/ml). NOTE - Perchloric acid lg about 1.67 gml) may also be used. 100 ml of perchloric acid (g ab
20、out 1.54 g/ml) is equivalent to 79 ml of per- chloric acid (g about 1,67 glrnil. 2 Reference 4.4 Copper. standard solution. ISO/R 377, Sdection and preparation of samples and test pieces for wrought steel. 3 Principie Dissolution of a test portion in a mixture of hydrochloric, nitric and perchloric
21、acids. Spraying of the solution into an air-acetylene flame. Spec- trometric measurement of the atomic absorption of the 324,7 nm spectral line emitted by a copper hdlow cathode lamp. 4 Reagents During the analysis, unless otherwise stated, use only reagents of recognized analytical grade and having
22、 a very low copper content, and only distilled water or water of equivalent purity. If possible, use only freshly prepared distilled or de-ionized water. 4.1 Iron of high purity, copper content 99,s % Imlm) Cul. Transfer to a 400 ml beaker and dissolve in 25 mi of nitric acid (e about 1,40 g/ml, dil
23、uted 1 + 4). Cover with a watch-glass. When dissolution is complete, evaporate on a water-bath until the onset of crystallization. Dissolve the residue in water, cool, transfer to a 1 O00 ml one-mark volumetric flask, dilute to the mark and mix. 4.4.2 Standard solution, corresponding to 20 mg of Cu
24、per litre. Transfer 20,O mi of the stock solution (4.4.1 into a 1 O00 ml one-mark volumetric flask, dilute to the mark and mix. 1 ml of this standard solution contains 20 pg of Cu. Prepare this standard solution immediately before use. 5 Apparatus Ordinary laboratory apparatus, and 5.1 Atomic absorp
25、tion spectrometer. A copper hdlow cathode tamp; suppks of air and acetylene sufficiently pure to give a steady clear fuel-lean flame, free from water and oil, and free from copper. Page 4 EN 24 943 : 1990 The atomic absorption spectrometer used will be satisfactory if after optimization according to
26、 7.3.4 the limit of detection and characteristic concentration are in reasonable agreement .with the values given by the manufacturer and it meets the precision criteria given in 5.1.1. 5.1.1 Minimum precision Calculate the standard deviation of 10 measurements of the ab- sorbance of the most concen
27、trated calibration solution. The standard deviation shall not exceed 1,0 % of the mean ab- sorbance. Calculate the standard deviation of 10 measurements of the ab- sorbance of the least concentrated calibration solution (excluding the zero member). The standard deviation shall not exceed 0,5 % of th
28、e mean absorbance of the most concen- trated calibration solution. It is also desirable that the instrument should conform to the additional performance requirements given in 5.1.1.1 to 5.1.1.3. 5.1.1.1 Characteristic concentration The characteristic concentration for copper in a matrix similar to t
29、he final test portion solution shall be better than O, 10 pg of Cu per millilitre. 5.1.1.2 Limit of detection This is defined as twice the standard deviation of 10 measurements of the absorbance of a solution containing the appropriate element of a concentration level selected to give an absorbance
30、just above that of the zero member. The limit of detection of copper in a matrix similar to the final test portion solution shall be better than 0,15 pg of Cu per millilitre. expansion factor, the value can be calculated by measuring a suitable solution with and without scale expansion and simply di
31、viding the signal obtained. 6 Sampling Carry out sampling in accordance with ISO/R 377 or ap- propriate national standards for cast iron. 7 Procedure WARNING - Perchloric acid vapour may cause ex- plosions in the presence of ammonia. nitrous fumes or organic matter in general. Ensure that the spray
32、system and drainage system are washed free from perchloric acid after use. NOTE - All glassware shall first be washed in hydrochloric acid (g about 1,19 g/ml, diluted 1 + 11, then in water. The quantity of cop- per present in the beakers and flasks can be checked by measuring the absorption of the d
33、istilled water introduced into the glassware after the acid wash. 7.1 Test portion Weigh, to the nearest 0,001 g, approximately 0.5 g of the test sample. 7.2 Blank test Parallel with the determination and following the same procedure, carry out a blank test using the same quantities of all the reage
34、nts. 7.3 Determination 5.1.1.3 Graph linearity The slope of the calibration graph covering the top 20 % of the concentration range (expressed as a change in absorbance) shall not be less than 0,7 times the value of the slope for the bottom 20 % of the concentration range (expressed as a change in ab
35、sorbance) determined in the same way. For instruments with automatic calibration using two or more standards, it shall be established prior to the analysis, by ob- taining absorbance readings, that the above requirements for graph lineariry are fulfilled. 5.2 Ancillary equipment. A strip chart recor
36、der and/or digital readout device is recom- mended to evaluate the criteria in 5.1.1 and for all subsequent measurements. Scale expansion can be used until the noise observed is greater than the read-out error and is always recommended for absor- bances below O, 1. If scale expansion has to be used
37、and the in- strument does not have the means to read the value of the scale 7.3.1 Place the test portion (7.1) in a 250 ml beaker. Add, in small portions, 20 ml of the hydrochloric acid-nitric acid-perchloric acid mixture (4.31, cover the beaker with a watch-glass and heat gently until solvent actio
38、n ceases. Evaporate until dense white fumes of perchloric acid appear. Continue fuming for 1 min at such a temperature as to maintain a steady reflux of white perchloric acid fumes on the walls of the beaker. Preparation of the test solution NOTE - For samples not readilysoluble in the hydrochloric
39、acid-nitric acid-perchloric acid mixture (4.31, first dissolve in 10 ml of the hydrochloric acid-nitric acid mixture 14.2) before adding the 20 ml of the hydrochloric acid-nitric acid-perchloric acid mixture (4.3). Allow to cool, add 25 ml of water and heat gently to dissolve salts. Cool again and t
40、ransfer quantitatively to a 100 ml one- mark volumetric flask. Dilute to the mark and mix. Filter by decantation through a dry medium filter paper to remove any residue or precipitate, for example graphite, silica or tungstic acid, and collect the filtrate in a dry beaker after discarding the first
41、runnings. Page 5 EN 24 943 : 1990 Type of lamp Wavelength Flame Lamp current Bandwidth If the expected copper content of the test sample exceeds 0.1 % (m/m 1, the solution shall be diluted as follows. Copper hollow cathode 324,7 nm Air-acetylene slightiy lean flame adjusted for maximum copper respon
42、se Follow manufacturers recom- mendations Follow manufacturers recom- mendations Transfer 20,O mi of the solution to a 100 ml onemark volumetric flask, dilute to the mark and mix. NOTE - If the sdution has to be diluted to give the test solution, the blank test (7.2) must be diluted in the same way.
43、 7.3.2 Preparation of the calibration solutions Place 10 f 0.01 g of the iron (4.1) in a 1 litre beaker. Add in small portions 400 ml of the hydrochloric acid-nitric acid- perchloric acid mixture (4.3) and heat gently until dissolved. When dissolution is complete, evaporate until dense white fumes o
44、f perchloric acid appear. Continue fuming for 1 min at such a temperature as to maintain a steady reflux of white per- chloric acid fumes on the walls of the beaker. Allow to cool, add 100 ml of water and heat gently to dissolve salts. Cool again and transfer the solution quantitatively to a 500 ml
45、onemark volumetric flask. Dilute to the mark and mix. 7.3.2.1 Copper content ._ .- i 0,Ol 0,008 0,006 O, 004 O, 003 0,002 o, O01 0,ooO 8 0,000 6 0,000 4 Annex B Graphical representation of precision data (This annex does not form part of this International Standard.) c -0-R -er 0,005 op1 0,02 0,05 0,1 02 0.5 1 2 5 Coppercontent i% (rnlrn)l Figure - Relationship between copper content and repeatability, r, or reproducibility, R
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