《BS-ISO-22961-2008.pdf》由会员分享，可在线阅读，更多相关《BS-ISO-22961-2008.pdf（14页珍藏版）》请在三一文库上搜索。
1、BRITISH STANDARD BS ISO 22961:2008 Titanium and titanium alloys Determination of iron Atomic absorption spectrometry ICS 77.120.50 ? Copyright British Standards Institution Provided by IHS under license with BSI - Uncontrolled Copy Licensee=Boeing Co/5910770001 Not for Resale, 08/14/2008 22:29:35 MD
2、TNo reproduction or networking permitted without license from IHS -,-,- BS ISO 22961:2008 This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 May 2008 BSI 2008 ISBN 978 0 580 57634 8 National foreword This British Standard is the UK implementa
3、tion of ISO 22961:2008. The UK participation in its preparation was entrusted to Technical Committee NFE/35, Light metals and their alloys. A list of organizations represented on this committee can be obtained on request to its secretary. This publication does not purport to include all the necessar
4、y provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard cannot confer immunity from legal obligations. Amendments/corrigenda issued since publication DateComments Copyright British Standards Institution Provided by IHS under license with BSI
5、- Uncontrolled Copy Licensee=Boeing Co/5910770001 Not for Resale, 08/14/2008 22:29:35 MDTNo reproduction or networking permitted without license from IHS -,-,- Reference number ISO 22961:2008(E) INTERNATIONAL STANDARD ISO 22961 First edition 2008-01-15 Titanium and titanium alloys Determination of i
6、ron Atomic absorption spectrometry Titane et alliages de titane Dosage du fer Spectromtrie dabsorption atomique BS ISO 22961:2008 Copyright British Standards Institution Provided by IHS under license with BSI - Uncontrolled Copy Licensee=Boeing Co/5910770001 Not for Resale, 08/14/2008 22:29:35 MDTNo
7、 reproduction or networking permitted without license from IHS -,-,- ii Copyright British Standards Institution Provided by IHS under license with BSI - Uncontrolled Copy Licensee=Boeing Co/5910770001 Not for Resale, 08/14/2008 22:29:35 MDTNo reproduction or networking permitted without license from
8、 IHS -,-,- iii Contents Page Foreword iv 1 Scope . 1 2 Normative references. 1 3 Principle. 1 4 Reagents 1 5 Apparatus 2 6 Sample . 3 7 Procedure 3 8 Expression of results . 5 9 Precision 6 Bibliography. 7 BS ISO 22961:2008 Copyright British Standards Institution Provided by IHS under license with B
9、SI - Uncontrolled Copy Licensee=Boeing Co/5910770001 Not for Resale, 08/14/2008 22:29:35 MDTNo reproduction or networking permitted without license from IHS -,-,- iv Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member b
10、odies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental a
11、nd non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives
12、, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies ca
13、sting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 22961 was prepared by Technical Committee ISO/TC 79, Light metals and their alloys,
14、 Subcommittee SC 11, Titanium. BS ISO 22961:2008 Copyright British Standards Institution Provided by IHS under license with BSI - Uncontrolled Copy Licensee=Boeing Co/5910770001 Not for Resale, 08/14/2008 22:29:35 MDTNo reproduction or networking permitted without license from IHS -,-,- 1 Titanium a
15、nd titanium alloys Determination of iron Atomic absorption spectrometry 1 Scope This International Standard specifies an atomic absorption spectrometric method for the determination of the mass fraction of iron in titanium and titanium alloys. The method is applicable to titanium and titanium alloys
16、 with a mass fraction of iron in the range from 0,005 % to 2,0 %. 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 docum
17、ent (including any amendments) applies. ISO 384:1978, Laboratory glassware Principles of design and construction of volumetric glassware ISO 648:1), Laboratory glassware Single volume pipettes ISO 1042:1998, Laboratory glassware One-mark volumetric flasks ISO 3696:1987, Water for analytical laborato
18、ry use Specifications and test methods ISO 4787:1984, Laboratory glassware Volumetric glassware Methods for use and testing of capacity 3 Principle Dissolve the test portion in hydrochloric acid and hydrofluoric acid. Add nitric acid to oxidize titanium, iron and other elements. Then add boric acid,
19、 determine the iron concentration in the test portion using an atomic absorption spectrometer. 4 Reagents 4.1 General During the analysis, use only reagents of recognized analytical grade and water that complies with grade 2 of ISO 3696. 1) To be published. (Revision of ISO 648:1977) BS ISO 22961:20
20、08 Copyright British Standards Institution Provided by IHS under license with BSI - Uncontrolled Copy Licensee=Boeing Co/5910770001 Not for Resale, 08/14/2008 22:29:35 MDTNo reproduction or networking permitted without license from IHS -,-,- 2 4.2 Hydrochloric acid (1+ +1) Add slowly 500 ml of hydro
21、chloric acid (20 1,16 g/ml to 1,19 g/ml) to 500 ml of water. 4.3 Nitric acid (1+ +1) Add slowly 500 ml of nitric acid (20 1,42 g/ml) to 500 ml of water. 4.4 Hydrofluoric acid (1+ +1) Add, carefully and slowly, 100 ml of hydrofluoric acid (20 1,14 g/ml) to 100 ml of water. 4.5 Boric acid 4.6 Titanium
22、 Titanium with minimum purity 99 % (mass fraction) and the mass fraction of iron as low as possible, and already known. If the mass fraction of iron is unknown, it should be determined by ISO 22960. 4.7 Iron standard solution 4.7.1 Iron standard stock solution (0,500 mg Fe/ml) Weigh, to the nearest
23、0,1 mg, 0,500 g of iron metal minimum purity 99,9 % (mass fraction) into a 300 ml beaker, heat and decompose with 30 ml of hydrochloric acid (4.2). Add 5ml of nitric acid (4.3) to oxidize iron and heat until nitrogen oxides evaporates. After cooling, transfer to a 1 000 ml volumetric flask, make up
24、to the mark with water and mix. 4.7.2 Iron standard solution (0,050 mg Fe/ml) Pipette 10,00 ml of iron standard stock solution (4.7.1) to a 100 ml volumetric flask, make up to the mark with water and mix. Prepare this solution on the day of use. 5 Apparatus 5.1 General Use normal laboratory apparatu
25、s. 5.2 Volumetric glassware, of class A complying with ISO 384, ISO 648 and ISO 1042. Use in accordance with ISO 4787. 5.3 Analytical balance, sensitive to 0,1 mg. 5.4 Atomic absorption spectrometer. Instrumental conditions: Flame: air/acetylene Wavelength: 248,3 nm BS ISO 22961:2008 Copyright Briti
26、sh Standards Institution Provided by IHS under license with BSI - Uncontrolled Copy Licensee=Boeing Co/5910770001 Not for Resale, 08/14/2008 22:29:35 MDTNo reproduction or networking permitted without license from IHS -,-,- 3 6 Sample 6.1 Sampling The sampling procedure for titanium and titanium all
27、oys shall be agreed upon until a corresponding standard method has been published. 6.2 Test portion Extract a test portion of 0,50 g from the test sample and weigh to the nearest 0,1 mg. 7 Procedure 7.1 Number of determinations Carry out the determination at least in duplicate, as far as possible un
28、der repeatability conditions, on each sample. 7.2 Blank test Carry out a blank test in parallel with the analysis, using the same quantities of all reagents but omitting the test portion. 7.3 Preparation of calibration solution 7.3.1 General Prepare the calibration solutions in accordance with 7.3.2
29、 or 7.3.3. 7.3.2 In the case of a mass fraction of iron less than 0,1 % Weigh six samples of titanium (4.6), each of 0,50 g, and transfer to polyethylene beakers (200 ml). Add 10 ml of hydrochloric acid (4.2) and 5 ml of hydrofluoric acid (4.4), cover with a polyethylene watch glass and heat gently
30、on a water bath to decompose the test portion. Add 3 ml of nitric acid (4.3) and continue heating until nitrogen oxides are evaporated. Then add 3 g of boric acid (4.5), stir to dissolve the boric acid and cool to room temperature. Transfer the solution into a 100 ml volumetric flask and add, from a
31、 burette or pipette, 0 ml, 2 ml, 4 ml, 6 ml, 8 ml and 10 ml of iron standard solution (4.7.2). Make up to the mark with water and mix. 7.3.3 In the case of a mass fraction of iron more than 0,1 % Weigh 0,50 g of titanium (4.6) and transfer to a polyethylene beaker (200 ml). Add 10 ml of hydrochloric
32、 acid (4.2) and 5 ml of hydrofluoric acid (4.4), cover with a polyethylene watch glass and heat gently on a water bath to decompose the titanium. Add 3 ml of nitric acid (4.3) and continue heating until nitrogen oxides are evaporated. Then add 3 g of boric acid (4.5), stir to dissolve the boric acid
33、 and cool to room temperature. Transfer the solution into a 100 ml volumetric flask. Pipette 20,0 ml or 5,0 ml of the solution according to the mass fraction of iron in the sample (see Table 1) into six volumetric flasks. Add 8 ml or 9,5 ml of hydrochloric acid (4.2) according to the mass fraction o
34、f iron in the sample (see Table 1). Add, from a burette or pipette, 0 ml, 2 ml, 4 ml, 6 ml, 8 ml and 10 ml of iron standard solution (4.7.2). Make up to the mark with water and mix. BS ISO 22961:2008 Copyright British Standards Institution Provided by IHS under license with BSI - Uncontrolled Copy L
35、icensee=Boeing Co/5910770001 Not for Resale, 08/14/2008 22:29:35 MDTNo reproduction or networking permitted without license from IHS -,-,- 4 7.4 Preparation of test solution for presentation to atomic absorption spectrometer Transfer the test portion to a polyethylene beaker (200 ml). Add 10 ml of h
36、ydrochloric acid (4.2) and 5 ml of hydrofluoric acid (4.4), cover with a polyethylene watch glass and heat gently on a water bath to decompose the test portion. Add 3 ml of nitric acid (4.3) and continue heating until nitrogen oxides are evaporated. Then add 3 g of boric acid (4.5), stir to dissolve
37、 the boric acid and cool to room temperature. Transfer the solution into a 100 ml volumetric flask, make up to the mark with water and mix. In case the mass fraction of iron is more than 0,1 %, pipette 20,0 ml or 5,0 ml of the solution according to the mass fraction of iron in the sample into a 100
38、ml volumetric flask. Add 8 ml or 9,5 ml of hydrochloric acid (4.2) according to the aliquot volume, and make up to the mark with water (see Table 1). Table 1 Mass fractions of iron and aliquot volume Mass fraction of iron Aliquot volume Added volume of HCl (4.2) % ml ml W 0,1 0,5 W 0,5 u 2 20,0 5,0
39、8 9,5 7.5 Determination of iron concentration 7.5.1 General The instrument shall be set up with an iron hollow cathode lamp in accordance with the manufacturers recommendation. The wavelength shall be set to 248,3 nm. An oxidizing acetylene-air flame is used. When using devices for a computer system
40、 preparation of a working curve, standardization (drift correction, normalization, recalibration) and measurement of iron concentration shall be in accordance with the operating manual for the devices computer system software. 7.5.2 Preparation of working curve Spray a portion of the calibration sol
41、utions into the air and acetylene flame of an atomic absorption spectrometer of which the zero point has been regulated by using water, measure the absorbance at a wavelength of 248,3 nm, prepare the relation curve between the obtained absorbance and iron concentration in milligrams per 100 ml. Prep
42、are the working curve for a sample by parallel shifting of the relation curve, so as to let the curve pass through the origin of the coordinate axes. 7.5.3 Measurement of iron concentration Spray a portion of the test solutions into the air and acetylene flame of an atomic absorption spectrometer of
43、 which the zero point has been regulated by using water, measure the absorbance at a wavelength of 248,3 nm, and determine the iron concentration (mg/100 ml) of the test solutions from the working curve. BS ISO 22961:2008 Copyright British Standards Institution Provided by IHS under license with BSI
44、 - Uncontrolled Copy Licensee=Boeing Co/5910770001 Not for Resale, 08/14/2008 22:29:35 MDTNo reproduction or networking permitted without license from IHS -,-,- 5 8 Expression of results 8.1 In the case of a mass fraction of iron less than 0,1 % (m/m) The mass fraction of iron in the test portion, W
45、Fe, expressed as a percentage, is given by the following equation: W m = 3123 Fe () 10010 (1) where 1 is the concentration of iron in the test solution, expressed in mg/100 ml; 2 is the concentration of iron in the blank solution, expressed in mg/100 ml; 3 is the concentration of iron in the titaniu
46、m (4.6) used in 7.3.2 or 7.3.3, expressed in mg/100ml; m is the mass of test portion, expressed in g. Calculate the mass fraction of iron in the test portion to the third decimal place. The difference in results of two parallel determinations of oxygen content in the same sample shall not be greater
47、 than the tolerance Equation (3), (4) or (5). If the difference exceeds the tolerance, the analysis shall be repeated. 8.2 In the case of a mass fraction of iron more than 0,1 % The mass fraction of iron in the test portion, WFe, expressed as a percentage, is given by the following equation: V W m = 453 3 Fe 100 100 10 (2) where 3 is the concentration of iron in the titanium used in 7.3.2 or 7.3.3, expressed in mg/100 ml; 4 is the concentration of iron in the aliquot test solution expressed in mg/100 ml; 5 is the concentration of iron in the aliquot blank solution expressed in m