International Standard (ISo 7627/2 INTERNATIONAL ORGANIZATION FOR STANDARDIZATIONMEXAYHAPOAHAR OPTAHM3AUMA IO CTAHAAPTW3ALMW-ORGANISATION INTERNATIONALE DE NORMALISATION Hardmetals -- Chemical analysis by flame atomic absorption spectrometry Part 2: Determination of calcium, potassium, magnesium and sodium in contents from 0,001 to 0,02 % (m/m) Metaux-durs --Analyse chimique par spectrometrie d'absorption atomique dans la flamme -Partie 2:Dosage du calcium, du potassium,dumagnésiumetdusodiumadesteneurscomprisesentreo,o01et0,02%(m/m) First edition - 1983-10-15 ISO 7627/2-1983 (E) UDC 669.018.25 : 643.422 Ref. No. ISO 7627/2-1983 (E) Descriptors: hardmetais, chemical analysis, determination of content, calcium, potassium, magnesium, sodium, atomic absorption spectrometry. Price based on 2 pages Foreword ISo (the International Organization for Standardization) is a worldwide federation of national standards bodies (Iso member bodies). The work of developing International 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 Internationai Standards by the Iso Council. International Standard ISo 7627/2 was developed by Technical Committee ISO/Tc 119, Powder metallurgy, and was circulated to the member bodies in August 1982. It has been approved by the member bodies of the following countries : Austria Germany, F.R. Spain Brazil Italy Sweden Bulgaria Korea, Rep. of Switzerland China Norway United Kingdom Czechoslovakia Poland USA Egypt, Arab Rep. of Romania USSR France South Africa, Rep. of No member body expressed disapproval of the document. @ International Organization for Standardization, 1983 Printed inSwitzerland INTERNATIONAL STANDARD ISO 7627/2-1983 (E) Hardmetals - Chemical analysis by flame atomic absorption spectrometry Part 2: Determination of calcium, potassium, magnesium and sodium in contents from 0,001 to 0,02 % (m/m) Scope and field of application 4Procedure ThispartofISO7627specifiesthemethodtobeusedforthe 4.1 Test portion determination of calcium, potassium, magnesium and sodium contentsofhardmetalswithintherange0,001to0,02%(m/m) Weigh, to the nearest 0,001 g, approximately 1 g of the test byflameatomicabsorptionspectrometry. sample. Transfer it to a 100 ml polytetrafluorethylene beaker or a beaker of other suitable material. Cover the beaker. General requirements concerning the field of application, prin- ciple, interfering elements, apparatus, sampling and test report aregiveninISo7627/1. 4.2 Dissolution of the test portion NOTE --- In low concentrations, the determination of these elements is Add 10 ml of water, 5 ml of the hydrofluoric acid (3.1), and very critical.Everycare should betakentoavoid contamination from then 5 ml of the nitric acid (3.2), drop by drop, to the beaker atmosphere and reagents. containing the test portion (4.1) and heat gently until the test portion is completely dissolved. Add 10 ml of the caesium chloride solution (3.4) and 10 ml of the ammonium fluoride 2 Reference solution (3.3). Then transfer the solution totally to a 100 ml polypropylene one-mark volumetric flask and dilute to the ISo 7627/1, Hardmetals - Chemical analysis by flame atomic mark. absorptionspectrometry-Part1:Generalrequirements. 4.3 Dilution volume Reagents Prepare the relevant dilution volume for the analysis according 3 tothetableas follows: If necessary, reagents of the highest purity shall be used. 4.3.1 Dilution volume 100 ml: use the solution in 4.2. 3.1 Hydrofluoric acid, @ 1,12 g/ml. 4.3.2 The concentration of the solution may be reduced by a factor of 10 for instruments of higher sensitivity by transferring 3.2 Nitric acid, 1,42 g/ml. 10 mi of the soiution in 4.2 to a i00 mi poiypr