(iso International Standard 4742 INTERNATIONAL ORGANIZATION FOR STANDARDIZATIONMEKAYHAPOAHAR OPrAHM3AUWR NO CTAHAAPTM3AUWM-ORGANISATION INTERNATIONALE DE NORMALISATION Copper alloys - Determination of nickel content Gravimetric method Alliages de cuivre - Dosage du nickel -- Methode gravimetrique First edition -- 1984-03-15 ISO 4742-1984 (E) UDC 669.35: 543.21:546.74 Ref. No. 1SO 4742-1984 (E) Descriptors : copper, copper alloys, chemical analysis, determination of content, nickel, gravimetric analysis. Price based on 2 pages Licensee=NASA Technical Standards 1/9972545001 No reproduction or networking permitted without license from IHS Foreword Iso (the international Organization for Standardization) is a worldwide federation of national standards bodies (Iso member bodies). The work of developing International Standards is carried out through ISo technical committees. Every member body interested in a subject for which a technical committee has been authorized has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with Iso, also take part in the work. Draft International Standards adopted by the technical committees are circulated to the member bodies for approval before their acceptance as International Standards by the Iso Council. International Standard ISO4742wasdevelopedbyTechnical CommitteeISO/TC26, Copper and copper alloys, and was circulated to the member bodies in December 1981. It has been approved by the member bodies of the following countries : Australia Germany, F.R. Poland Austria Hungary Romania Belgium India South Africa, Rep. of Bulgaria Italy Spain Canada Japan Sweden China Korea, Dem. P. Rep. of Switzeriand Czechoslovakia Korea,Rep.of Turkey Egypt, Arab Rep. of Netherlands USA France Norway USSR No member body expressed disapproval of the document. @ International Organization for Standardization, 1984 Printed in Switzerland NASA 1/9972545001 No reproduction or networking permitted without license from IHS Not for Resale, 04/25/2007 19:52:30 MDT ISO4742-1984(E) INTERNATIONALSTANDARD Copper alloys -- Determination of nickel content Gravimetric method WARNING : Throughout this International Standard, normal precautions regarding the use of perchloric acid in laboratory work should be observed. Scope and field of application 4.6 Sulfamic acid, 100 g/l solution. This International Standard specifies agravimetric methodfor 4.7 Citric acid, 250 g/l solution. the determination of the nickel content in all types of copper alloys listed in international Standards. 4.8 Sodium dimethylglyoximate, 25,9 g/l solution. The method is applicable to the determination of nickel con- tents between 2 and 50 % (m/m). 5 Apparatus Reference Ordinary laboratory apparatus, and ISo 1554,Wrought and cast copper alloys-Determination of copper content - Electrolytic method. 5.1 Beakers, electrolytic, capacity 300 to 400 ml. 5.2 Electrolysis equipment, including current source and 3Principle platinum electrodes, as specified in iso 1554. Dissolution of a test portion in nitric acid and removal of tin and 5.3 Filter crucible, of fritted glass, pore size 16 to 40 μm. silicon, if present. Separation of copper by electrolysis and precipitation of nickel from the copper-free electrolysate by the sodium salt of dimethylglyoxime in the presence of citric acid. Separation of the precipitate by filtration. 6 Procedure Reagents 6.1 Test portion 4 6.1.1Nickelcontentbetween2and4,25% (m/m) grade and only distilled water or water of equivalent purity. Weigh, to the nearest 0,000 1 g, about 2 g of the test sample. 4.1 Nitric acid, Q 1,40 g/ml. The nickel content of the test portion will be 40 to 85 mg. 4.2 Perchloric acid, 1,67 g/ml. 6.1.2.Nickel content between 4and 8,5% (m/m) Weigh, to the nearest 0,000 1 g, about 1 g of the test sample. 4.3 Hydrobromic acid, @ 1,38 g/ml. The nickel content of the test portion will be 40 to 85 mg. 4.4 Ammonia solution,@0,925 g/ml. 6.1.3 Nickel c