1、BRITISH STANDARD BS 6200-3.1.4: 1990 EN 29658:1991 ISO 9658:1990 Incorporating Amendment No. 1 Sampling and analysis of iron, steel and other ferrous metals Part 3: Methods of analysis Section 3.1 Determination of aluminium Subsection 3.1.4 Non-alloyed steel: flame atomic absorption spectrometric me
2、thod The European Standard EN 29658:1991 has the status of a British StandardBS 6200-3.1.4:1990 This British Standard, having been prepared under the directionof the Iron and Steel Standards Policy Committee, waspublished under the authorityof the Board of BSI andcomes into effect on 30 November 199
3、0 BSI 09-1999 First published May 1985 Second edition November 1990 The following BSI references relate to the work on this standard: Committee reference ISM/18 Draft for comment 88/38042 DC ISBN 0 580 19028 5 Committees responsible for this British Standard The preparation of this British Standard
4、was entrusted by the Iron and Steel Standards Policy Committee (ISM/-) to Technical Committee ISM/18, upon which the following bodies were represented: BCIRA British Forging Industry Association British Steel Industry Department of Trade and Industry (Laboratory of the Government Chemist) Ferro Allo
5、ys and Metals Producers Association Ministry of Defence Amendments issued since publication Amd. No. Date Comments 7087 July 1992 Indicated by a sideline in the marginBS 6200-3.1.4:1990 BSI 09-1999 i Contents Page Committees responsible Inside front cover National foreword ii Foreword 2 1 Scope 3 2
6、Normative references 3 3 Definition 3 4 Principle 3 5 Reagents 3 6 Apparatus 4 7 Sampling 4 8 Procedure 4 9 Expression of results 7 10 Test report 8 Annex A (normative) Procedures for the determination of instrumentalcriteria 9 Annex B (informative) Additional information on the international co-ope
7、rativetests 11 Annex C (informative) Graphical representation of precision data 11 Figure A.1 10 Figure C.1 Logarithmic relationship between acid-soluble aluminium content(m) and repeatability (r) or reproducibility (R and R w ) 11 Figure C.2 Logarithmic relationship between total aluminium content
8、(m) and repeatability (r) or reproducibility (R and R w ) 12 Table 1 6 Table 2 6 Table 3 6 Table 4 8 Table B.1 11 Publication(s) referred to Inside back coverBS 6200-3.1.4:1990 ii BSI 09-1999 National foreword This Subsection of BS6200 has been prepared under the direction of the Iron and Steel Stan
9、dards Policy Committee. It supersedes BS 6200-3.1.4:1985, which is withdrawn. It is identical with ISO 9658:1990 “Steel Determination of aluminium content Flame atomic absorption spectrometric method”, published by the International Organization for Standardization (ISO). In 1991 the European Commit
10、tee for Standardization (CEN) accepted ISO9658:1990 as European Standard EN 29658:1991. The Technical Committee has reviewed the provisions of ISO377, ISO385-1 and ISO648, to which reference is made in the text, and has decided that they are acceptable for use in conjunction with this standard. Rela
11、ted British Standards for ISO377:1989, ISO385-1:1984 and ISO648:1977 are, respectively, BS1837:1970 “Methods for the sampling of iron, steel, permanent magnet alloys and ferro-alloys”, BS846:1985 “Specification for burettes” and BS1583:1986 “Specification for one-mark pipettes”. Appropriate procedur
12、es from ISO377 will be incorporated in BS6200-2 “Methods of sampling and sample preparation”, which will be published in due course and which will supersede BS 1837. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible
13、for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Cross-references International Standard Corresponding British Standard ISO 1042:1983 BS 1792:1982 Specification for one-mark volumetric flasks (Identical) ISO 5725:1986 BS 549
14、7 Precision of test methods Part 1:1987 Guide for the determination of repeatability and reproducibility for a standard test method by inter-laboratory tests (Identical) Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, theEN title page, pages2 to12, an i
15、nside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 29658:1991 December 1991 UDC 669.14:620.1:543.
16、422.41.6:546.62 Descriptors: Steels, unalloyed steels, chemical analysis, determination of content, aluminium, atomic absorption spectrophotometry, flame photometry English version Steel Determination of aluminium content Flame atomic absorption spectrometric method (ISO 9658:1990) Aciers Dosage de
17、laluminium Mthode par spectromtrie dabsorption atomique dans la flamme (ISO 9658:1990) Stahl Bestimmung des Aluminiumgehalts Spektralfotometrische Atomabsorptionsmethode (ISO 9658:1990) This European Standard was approved by CEN on 1991-12-20. CEN members are bound to comply with the CEN/CENELEC Int
18、ernal 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 national standards may be obtained on application to the Central Secretariat or to any CEN memb
19、er. 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 notified to the Central Secretariat has the same status as the official versions. CEN members
20、 are the national standards bodies of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and UnitedKingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches K
21、omitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels CEN 1991 Copyright reserved to all CEN members Ref. No. EN 29658:1991 EEN29658:1991 BSI 09-1999 2 Foreword On the proposal of the Technical Committee ECISS/TC20 the Coordinating Commission (COCOR) of the European Committee fo
22、r Iron and Steel Standardization (ECISS) decided in May 1991 to submit the International Standard ISO 9658:1990, Steel Determination of aluminium content Flame atomic absorption spectrometric method. to the formal vote. This European Standard EN29658 was approved by CEN on 1991-12-20. According to t
23、he CEN/CENELEC Internal Regulations, the following countries are bound to implement this European Standard: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the UnitedKingdom.EN29658:1991 B
24、SI 09-1999 3 1 Scope This International Standard specifies a flame atomic absorption spectrometric method for the determination of acid-soluble and/or total aluminium in non-alloyed steel. The method is applicable to aluminium contents between 0,005%(m/m) and0,20%(m/m). 2 Normative references The fo
25、llowing standards contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this International Standard are e
26、ncouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintain registers of currently valid International Standards. ISO 377:1989, Selection and preparation of samples and test pieces of wrought steels Part 1: Samples a
27、nd test pieces for mechanical test. ISO 385-1:1984, Laboratory glassware Burettes Part 1: General requirements. ISO 648:1977, Laboratory glassware One-mark pipettes. ISO 1042:1983, Laboratory glassware One-mark volumetric flasks. ISO 5725:1986, Precision of test methods Determination of repeatabilit
28、y and reproducibility for a standard test method by inter-laboratory tests. 3 Definition For the purposes of this International Standard, the following definition applies. acid-soluble aluminium aluminium dissolved in the acid mixture as specified in 8.3.1.1 4 Principle Dissolution of a test portion
29、 in dilute hydrochloric and nitric acids. Fusion of the acid-insoluble material with a mixture of orthoboric acid and potassium carbonate. Spraying of the solution into a dinitrogen monoxideacetylene flame. Spectrometric measurement of the atomic absorption of the 309,3 nm spectral line emitted by a
30、n aluminium hollow cathode lamp. 5 Reagents During the analysis, unless otherwise stated, use only reagents of recognized analytical grade and only distilled water or water of equivalent purity. 5.1 Pure iron, containing less than 0,0001% (m/m) of aluminium, or of low known aluminium content. 5.2 Hy
31、drofluoric acid, about 1,15g/ml. 5.3 Hydrochloric acid, about 1,19g/ml, diluted 1+1. 5.4 Hydrochloric acid, about 1,19g/ml, diluted 2+100. 5.5 Sulfuric acid, about 1,84g/ml, diluted 1+1. 5.6 Acid mixture Mix 3 parts by volume of hydrochloric acid ( about 1,19g/ml), 1 part by volume of nitric acid (
32、about 1,40g/ml) and 2 parts by volume of water. Prepare this mixture immediately before use. 5.7 Fusion mixture Mix 1 part by mass of orthoboric acid (H 3 BO 3 ) and 1part by mass of anhydrous potassium carbonate (K 2 CO 3 ). 5.8 Fusion mixture solution Dissolve 20,0g of the fusion mixture (5.7) in
33、water and dilute to 100ml. 5,0ml of this solution contain 1,0g of the fusion mixture (5.7). 5.9 Aluminium, standard solutions. 5.9.1 Stock solution, corresponding to 2,0 g of Al per litre. Weigh, to the nearest 0,001g, 2,000g of high purity aluminium U 99,9% (m/m) pure, and dissolve in40ml of hydroc
34、hloric acid ( about1,19g/ml) and10ml of nitric acid ( about1,40g/ml). Boil to eliminate oxides of nitrogen. Cool and transfer the solution quantitatively to a1000ml one-mark volumetric flask. Dilute to the mark with water and mix. 1 ml of this solution contains 2,0mg of Al. 5.9.2 Standard solution A
35、, corresponding to 0,20 g ofAl per litre. Transfer 20,0ml of the stock solution (5.9.1) into a 200ml one-mark volumetric flask. Dilute to the mark with water and mix. Prepare this standard solution immediately before use. 1ml of this solution contains0,20mg of Al. 5.9.3 Standard solution B, correspo
36、nding to 0,020g of Al per litre. Transfer20,0ml of the standard solution A (5.9.2) into a200ml one-mark volumetric flask. Dilute to the mark with water and mix. Prepare this standard solution immediately before use.EN29658:1991 4 BSI 09-1999 1ml of this standard solution contains 0,020mg ofAl. 6 App
37、aratus All volumetric glassware shall be class A, in accordance with ISO385-1, ISO648 or ISO1042 as appropriate. All glassware shall be cleaned with hot hydrochloric acid (5.3) and then water. Ordinary laboratory apparatus, and 6.1 Filter media, 0,45 4m cellulose nitrate filter. 6.2 Filter funnel, t
38、wo-piece acid-resistant filter funnel with a support screen between the funnel body and stem, designed for the vacuum filtration of liquids. The stem of the funnel is fitted with a ground glass cap stopper or a rubber stopper for insertion into an opening of the vacuum vessel. 6.3 Vacuum vessel, fla
39、sk of capacity500ml, or large enough to contain a100ml one-mark volumetric flask, with an opening to allow for insertion of the rubber stopper of the filter funnel stem. 6.4 Platinum crucible, of capacity 30ml. 6.5 Atomic absorption spectrometer An aluminium hollow cathode lamp; supplies of dinitrog
40、en monoxide and acetylene sufficiently pure to give a steady clear red-feather flame, free from water and oil, and free from aluminium. The atomic absorption spectrometer used will be satisfactory if after optimization according to 8.3.4 the limit of detection and characteristic concentration are in
41、 reasonable agreement with the values given by the manufacturer and if it meets the precision criteria given in6.5.1 to6.5.3. It is also desirable that the instrument should conform to the additional performance requirement given in6.5.4. 6.5.1 Minimum precision (see clause A.1). Calculate the stand
42、ard deviation of 10 measurements of the absorbance of the most concentrated calibration solution. The standard deviation shall not exceed1,5% of the mean absorbance. Calculate the standard deviation of10measurements of the absorbance of the least concentrated calibration solution (excluding the zero
43、 member). The standard deviation shall not exceed0,5% of the mean absorbance of the most concentrated calibration solution. 6.5.2 Limit of detection (see clause A.2). This is defined as twice the standard deviation of10measurements of the absorbance of a solution containing the appropriate element a
44、t a concentration level selected to give an absorbance just above that of the zero member. The limit of detection of aluminium in a matrix similar to the final test portion solution shall be better than0,14g of Al per millilitre. 6.5.3 Graph linearity (see clause A.3). The slope of the calibration g
45、raph covering the top20% of the concentration range (expressed as a change in absorbance) shall not be less than0,7times the value of the slope for the bottom20% of the concentration range determined in the same way. For instruments with automatic calibration using two or more standards, it shall be
46、 established prior to the analysis, by obtaining absorbance readings, that the above requirements for graph linearity are fulfilled. 6.5.4 Characteristic concentration (see clause A.4). The characteristic concentration for aluminium in a matrix similar to the final test portion solution shall be bet
47、ter than 1,0 4g of Al per millilitre. 6.6 Ancillary equipment A strip chart recorder and/or digital readout device is recommended to evaluate the criteria of6.5 and for all subsequent measurements. Scale expansion can be used until the noise observed is greater than the readout error and is always r
48、ecommended for absorbances below0,1. If scale expansion has to be used and the instrument does not have the means to read the value of the scale expansion factor, the value can be calculated by measuring a suitable solution with and without scale expansion and simply dividing the signal obtained. 7
49、Sampling Carry out sampling in accordance with ISO377 or appropriate national standards for steel. 8 Procedure 8.1 Test portion Weigh, to the nearest0,001g, approximately2,0g of the test sample. 8.2 Blank test Parallel with the determination and following the same procedure, carry out a blank test using the same quantities of all the reagents without the addition of pure iron. Background correction may be required.EN29658:1991 BSI 09-1999 5 8.3 Determination 8.3.1 Preparation of the test solution 8.3.1.1 Decomposit
