ISO/TC 17/SC 1 - Methods of determination of chemical composition

This document specifies an infrared absorption method after combustion in an induction furnace for the determination of the low carbon content in unalloyed steel. The method is applicable to carbon contents between 0,000 3 % (mass fraction) and 0,009 % (mass fraction).

This document specifies a potentiometric titration method for the determination of vanadium in steel and cast iron. The method is applicable to vanadium contents between 0,04 % (mass fraction) and 2 % (mass fraction).

This document specifies a flame atomic absorption spectrometric method (FAAS) for the determination of the vanadium content in steel. The method is applicable to vanadium contents between 0,01 % (mass fraction) and 0,80 % (mass fraction), provided that the tungsten content in a 1,0 g test portion is not higher than 1,0 % and/or the titanium content is not higher than 0,5 %.

This document specifies a gravimetric method for the determination of the silicon content in steel and cast iron. The method is applicable to silicon contents between 0,10 % (mass fraction) and 5,0 % {mass fraction). NOTE For samples containing molybdenum, niobium, tantalum, titanium, tungsten, zirconium or high levels of chromium, the results are less accurate than for unalloyed matrixes.

This document gives guidelines for the determination of the chemical composition of steel and iron by reference to published International Standards, including their range of application and principles of the methods. Graphical representation of the precision data precision data for the methods is given in Annex A. The list of International Standards is summarized in Annex B.

This document specifies a spectrophotometric method for the determination of nitrogen in steel. The method is applicable to the determination of nitrogen mass fraction between 0,000 6 % and 0,050 % in low alloy steels and between 0,010 % and 0,050 % in high alloy steels. The method does not apply to samples containing silicon nitrides or having silicon contents higher than 0,6 %.

This document specifies a potentiometric or visual titration method for the determination of manganese content in alloyed steels. The method is applicable to manganese mass fractions between 2 % and 25 %. Vanadium and cerium interfere with the determination. If the mass fraction of cerium in the sample is less than 0,01 %, or the mass fraction of vanadium in the sample is less than 0,005 %, the interference is negligible, otherwise theoretical corrections are necessary.

ISO 4829-1:2018 specifies a spectrophotometric method for the determination of total silicon in steel and cast iron using reduced molybdosilicate. The method is applicable to the determination of silicon mass fraction between 0,05 % and 1,0 %.

ISO/TS 10719:2016 specifies an infrared absorption method after combustion in an induction furnace for the determination of non-combined carbon content in cast irons. The method is applicable to non-combined carbon contents between 1,0 % (mass fraction) and 3,0 % (mass fraction). Elements ordinarily present do not interfere. However, some alloyed cast irons, when extensively heat treated, contain carbides that are not soluble when using this method and may give high values for non-combined carbon.

ISO/TR 21074:2016 describes how to determine the repeatability and reproducibility of precision tests performed within standardization work using the chemical analysis method. Specifically, this document explains the procedure for calculating precision, using precision test data of ISO 5725‑3:1994, Table D.2 for the precision test in ISO 9647:1989 as an example. The procedure of the international test for determining precision is described in ISO 5725‑2 and ISO 5725‑3.

ISO 4942:2016 specifies an N-benzoylphenylhydroxylamine (N-BPHA) spectrophotometric method for the determination of vanadium in steels and cast irons. It is applicable to vanadium contents between 0,005 % and 0,50 % (mass fraction).

ISO 4829-2:2016 specifies a spectrophotometric method for the determination of total silicon in steels using reduced molybdosilicate. The method is applicable to silicon contents between 0,01 % and 0,05 % (mass fraction) in steels.

ISO 4938:2016 specifies a method for the determination of nickel in steel and iron by gravimetry or titrimetry. The method is applicable to nickel contents from 1 % to 30 % (mass fraction).

ISO 4946:2016 specifies a spectrophotometric method for the determination of copper in steel and cast iron by 2,2'-biquinoline. The method is applicable to the determination of copper mass fraction in the range of 0,02 % and 5 %.

ISO 4939:2016 specifies a spectrophotometric method for the determination of nickel in steel using dimethylglyoxime. The method is applicable to the determination of nickel mass fractions in the range of 0,10 % and 2,0 %. Cobalt, copper and manganese can cause interferences (see 7.3.2).

ISO 19272:2015 specifies a glow discharge optical emission spectrometric (GD-OES) method for determination of the mass fraction Carbon, Silicon, Manganese, Phosphorus, Sulfur, Chromium, Nickel, Aluminium, Titanium and Copper in low alloyed steels. The content ranges to which the method is applicable are shown in Table 1. Table 1 ? Content ranges Element Content ranges mass fraction % C 0,060 to 0,35 Si 0,14 to 1,50 Mn 0,090 to 0,70 P 0,010to 0,070 S 0,005 to 0,050 Cr 0,008 to 0,65 Ni 0,050 to 0,50 Al 0,006 to 0,90 Ti 0,014 to 0,13 Cu 0,005 to 1,00

ISO 13933:2014 specifies a method for determination of calcium and magnesium contents in iron, cast iron, steel, and alloyed steel by inductively coupled plasma (ICP) atomic emission spectrometry. The method is applicable to the determination of calcium and magnesium contents (mass fraction) in the range of 0,000 5 % to 0,006 % and 0,000 5 % to 0,20 %, respectively.

ISO 17054:2010 specifies a procedure on how to improve the performance of a routine X-ray fluorescence spectrometry (XRF) method, already in use for analysis of high alloy steels, by using a "near by technique". The "near by technique" requires at least one target sample (preferably a CRM) of a similar composition as the unknown sample.

ISO 16918-1:2009 specifies a method for analysing steel and iron for the trace element determinations of Sn, Sb, Ce, Pb and Bi using inductively coupled plasma mass spectrometry (ICP-MS). The method is applicable for trace elements in the mass fraction ranges (µg/g) as follows: Sn: 5 µg/g to 200 µg/g; Sb: 1 µg/g to 200 µg/g; Ce: 10 µg/g to 1 000 µg/g; Pb: 0,5 µg/g to 100 µg/g; Bi: from 0,3 µg/g to 30 µg/g. Interferences in the determination of trace elements using ICP-MS are listed in Annex B.

ISO 13899-2:2005 specifies a method for the determination of the niobium content in steel by means of inductively coupled plasma emission spectrometry. This method is applicable to niobium contents between 0,005 and 5 % (mass fraction).

ISO/TS 13899-1:2005 specifies a method for the determination of tungsten content in steel by means of inductively coupled plasma atomic emission spectrometry.

ISO 17053:2005 specifies an infrared method after fusion under inert gas for the determination of oxygen in steel and iron. The method is applicable to mass fractions of oxygen between 0,000 75 % and 0,01 %.

ISO 17925:2004 specifies methods of determining the coating mass per unit area by gravimetry and chemical composition on one side-surface of zinc- and/or aluminium-based coatings on steel by means of inductively coupled plasma atomic emission spectrometric or flame atomic absorption spectrometry. This method is applicable to zinc contents between 40 % (mass fraction) and 100 % (mass fraction); aluminium contents between 0,02 % (mass fraction) and 60 % (mass fraction); nickel contents between 7 % (mass fraction) and 20 % (mass fraction); iron contents between 0,2 % (mass fraction) and 20 % (mass fraction); silicon contents between 0,2 % (mass fraction) and 10 % (mass fraction); lead contents between 0,005 % (mass fraction) and 2 % (mass fraction). These test methods are intended as referee methods to test such materials for compliance with mass per unit area and compositional specifications of International Standards.

ISO/TS 13899-1:2004 specifies an inductively coupled plasma atomic emission spectrometric method for the determination of molybdenum content in steel. The method is applicable to molybdenum contents between 0,03 % (mass fraction) and 8,5 % (mass fraction).

ISO 17058:2004 specifies a method for the determination of the arsenic content in steel and iron using a spectrophotometric method after distillation. The method is applicable to an arsenic content between 0,000 5 % (mass fraction) and 0,10 % (mass fraction).

ISO 4934:2003 specifies a gravimetric method for the determination of the sulfur content in steels and iron, excluding steels containing selenium. The method is particularly suitable as a reference method for the standardization of samples on which certified standard values are to be established. The method is applicable to a sulfur content between 0,003 % (mass fraction) and 0,35 %(mass fraction).

ISO/TR 17055 specifies a method for the determination of the content of silicon in steel by means of inductively coupled plasma emission spectrometry. The method is applicable to silicon contents of mass fraction 0,02 % to 5 %. The method uses a calibration based on a very close matrix matching of the calibration solutions to the sample and close bracketing of the contents around the approximate concentration of silicon in the sample to be analysed. The concentrations of all elements in the sample has, therefore, to be approximately known. If the concentrations are not known the sample has to be analysed by some semi quantitative method.

This International Standard specifies a method for the determination of tin in steel and iron by means of flame atomic absorption spectrometry. The method is applicable to tin contents in the range by mass to by mass.

This International Standard specifies an infrared absorption method, after combustion in an induction furnace, for the determination of the total carbon and sulfur content in steel and iron. The method is applicable to carbon contents of mass fraction between 0,005 % and 4,3 % and to sulfur contents of mass fraction between 0,000 5 % and 0,33 %. This method is intended to be used in normal production operations and is intended to meet all generally accepted, good laboratory practices of the type expected by recognized laboratory accreditation agencies. It uses commercially available equipment, is calibrated and calibration verified using steel and iron certified reference materials, and its performance is controlled using normal statistical process control (SPC) practices. This method can be used in the single element mode, i.e., determination of carbon and sulfur independently or in the simultaneous mode, i.e., determination of carbon and sulfur concurrently.

This International Standard specifies a potentiometric titration method for the determination of chromium content in steel and iron. The method is applicable to chromium contents between 1 % (m/m) and 35 % (m/m). Vanadium contents in steel and iron should be less than 1 % (m/m) for chromium contents higher than 10 % (m/m) and less than 0,2 % (m/m) for chromium contents less than 10 % (m/m).

This International Standard specifies a thermal conductimetric method after fusion under inert gas for the determination of nitrogen in steel and iron. The method is applicable to nitrogen contents between 0,002 % (m/m) and 0,6 % (m/m).

Gives methods for the determination of the chemical composition of pig iron, cast iron and steel. Methods are specified for use with both liquid and solid metal. Replaces ISO 377-2:1989.

Specifies an inductively coupled plasma atomic emission spectrometric method for the determination of the manganese content in unalloyed steels that is applicable to manganese contents between 0,002 % (m/m) and 1,5 % (m/m).

Cancels and replaces the first edition (1978). Specifies a thiocyanate spectrophotometric method for the determination of the molybdenum content in steel and iron. Applicable to molybdenum contents between 0,005 % (m/m) and 0,125 % (m/m). Vanadium and tungsten interfere with the measurement if, because of their contents, the V/Mo ratio is greater than 16 or the W/Mo ratio is greater than 8.

The principle of the method specified is dissolving a test portion in hydrochloric and nitric acids and dilution of the solution to a known volume, introducing a known volume of the solution into an electrothermal atomizer of an atomic absorption spectrometer, measuring the atomic absorption of the 217,6 nm spectral resonance line energy emitted by an antimony lamp. The method is applicable to antimony contents between 0,0005 % (m/m) and 0,010 % (m/m).

The principle of the method specified is dissolving a test portion in hydrochloric and nitric acids followed by evaporation with perchloric acid until white fumes appear, spraying the solution into an air-acetylene flame, spectrometrically measuring the atomic absorption of the 279,5 nm spectral line emitted by a manganese hollow cathode lamp. The method is applicable to manganese contents between 0,002 % (m/m) and 2,0 % (m/m).

The method specified is applicable to sulfur contents between 0,0003 % (m/m) and 0,010 % (m/m). However, niobium, silicon, tantalum and titanium interfere in the determination of sulfur, and application range and test portion masses of the method depend on the concentration of the interfering elements.

The principle of the method specified is dissolving a test portion in hydrochloric and nitric acids, fusing the acid-insoluble residue with sodium carbonate, adding potassium chloride/lanthanum nitrate solution as a spectrochemical buffer, spraying the solution into a dinitrogen monoxide-acetylen flame, and spectrometrically measuring the atomic absorption of the 422,7 nm spectral line emitted by a calcium hollow cathode lamp. The method is applicable to calcium contents betwen 0,0005 % (m/m) and 0,005 % (m/m).

The principle of the method specified is dissolving a test portion in hydrochloric acid followed by oxidation with hydrogen peroxide, fuming of the acid-insoluble residue in sulfuric acid with potassium sulfate and copper(II) sulfate, distilling the solution made alkaline with sodium hydroxide, collecting ammonia in a receiver containing orthoboric acid solution, titration of the ammonium ion with amidosulfuric acid. Is applicable to nitrogen contents from 0,002 % (m/m) to 0,5 % (m/m); does not apply to samples containing silicon nitride.

The method is applicable with the following limitations: phosphorus contents between 0,001 0 % (m/m) and 1,0 % (m/m), application ranges and test portions in table 1 depending on the concentration of the interfering elements (arsenic, hafnium, niobium, tantalum, titanium, tungsten).

Specifies the principle, the reagents, the apparatus, the sampling, the test procedure, the expression of results, the precision and the test report.

The publication of ISO 10138 gives rise to the cancellation of ISO 4936:1984. The method described determines chromium in non-alloy and low-alloy steels and iron. It is applicable to chromium contents between 0,002 % (m/m) and 2,0 % (m/m). Specifies normative references, principle, reagents, apparatus, sampling, procedure, expression of results and test report. Procedures for the determination of instrumental criteria are given in annex A. Additional information on the international co-operative tests are given in annex B, annex C represents the precision data graphically.

The method is applicable to the determination of acid-soluble and/or total aluminium content between 0,005 % (m/m) and 0,20 % (m/m). Specifies definition, principle, reagents, apparatus, sampling, procedure, expression of results and test report. The annexes give additional information on the international co-operative tests, a graphical representation of precision data and procedures for the determination of instrumental criteria.