8343 (ISO International Standard Ferronickel - Determination of silicon content Gravimetric method Ferro-nickel - Dosage du silicium - Methode gravimetrique First edition - 1985-10-15 Ref. No. ISO 8343-1985 (E) U DC 669.243.881 : 543.21 : 546.28 (3) ISO 8343-1985 Descriptors : nickel, ferronickel, chemical analysis, determination of content, silicon, gravimetric analysis. Price based on 2 pages Copyright International Organization for Standardization tted without license from IHS Not for Resale Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing nternational 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. Internationai organizations, govern- mental 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. They are approved in accordance with ISO procedures requiring at least 75 % approvat by the member bodies voting. International Standard ISO 8343 was prepared by Technical Committee ISO/TC 155 Nickel and nickel alloys. Users should note that ail International Standards undergo revision from time to time and that any reference made herein to any other International Standard implies its latest edition, unless otherwise stated. International Organization for Standardization, 1985 Printed in Switzerland CopyhenatonalrganizationStandardizatio tworking permited without license from IHS Not for Resale INTERNATIONAL STANDARD ISO 8343-1985 (E) Ferronickel - Determination of silicon content Gravimetric method 5 Apparatus 1 Scope and field of application This International Standard specifies a gravimetric method for Ordinary laboratory apparatus, and the determination of silicon in ferronickel in the range 0,2 to 4,0 % (m/m). 5.1 Beaker, high form, of capacity 600 ml, unetched. 5.2 Platinum crucible, of capacity 40 ml. 2 Reference 5.3 Muffle furnace, capable of being maintained at IS 5725, Precision of test methods - Determination of 1100 °C. repeatability and reproducibility by inter-laboratory tests. 5.4 Dessicator. 3 Principle 6 Sampling and samples Dissolution of a test portion in nitric acid and addition of per- chloric acid. Formation of insoluble silica by dehydration in 6.1 Sampling and preparation of the iaboratory sample shall perchloric acid, filtration, and weighing of the calcined pre- be carried out by normal agreed procedures or, in case of cipitate. Volatilization of the silica with hydrofiuoric and sulfuric dispute, by the relevant International Standard. acids, weighing of the residue, determination of the silica by difference and calculation of the silicon content. 6.2 The taboratory sample normally is in the form of granules, millings or drillings and no further preparation of the sample is necessary. 4 Reagents 6.3 If it is suspected that the laboratory sample is con- During the analysis, unless otherwise stated, use only reagents taminated with oil or grease from the milling or dilling process, it shalt be cleaned by washing with high purity acetone and dry- of recognized analyticat grade and only distilled water or water of equivalent purity. ing in air. 4.1 Hydrochloric acid, 020 = 1,19 g/ml. 6.4 If the laboratory sample contains particles or pieces of widely varying sizes, the test portion should be obtained by riffling. 4.2 Hydrochloric acid, 920 = 1,19 g/ml, diluted 1 + 9. 4.3 Hydrofluoric acid, Q20 = 1,14 g/ml. Procedure 7 WARNING - Hydrofluoric acid is extremely irritating and 7.1 Test portion corrosive to skin and mucous membranes, producing severe skin burns which are slow to heal. In case of skin 7.1.1 For a silicon content greater than