ISO/TC 33 - Refractories

This document specifies a test method for determining the compressive strength of refractory products at elevated temperature. This test method could also be used for materials development, quality control, characterization, design and data generation purposes. NOTE This document also could be used for determining the compressive strength of carbon containing refractory products at elevated temperature in an airtight furnace with reducing atmosphere.

This document describes the method for determining the permanent change in dimensions on heating (drying and/or firing) of refractory mortars.

This document specifies three methods for the determination of the bulk density of granular refractory materials (grain density) having a grain size larger than 2 mm: — Method 1: mercury method with vacuum; — Method 2: arrested water absorption method; — Method 3: vacuum method with spin dryer option according to ISO 5017. Method 1 is intended as the reference method. NOTE Depending on the nature of the material tested, the three methods can give different results. Any statement of the value of a bulk density can therefore be accompanied by an indication of the method used or to be used in case of dispute. The same method can be used for the determination of the volume of the sample, for selecting and preparing the sample, for calculating the bulk density and for presenting the test report.

This document describes methods for the determination of mineralogical phases often present as additives or reaction products in carbon containing or graphitic refractory products by X-ray Diffraction (XRD) using a Bragg-Brentano diffractometer. It includes details of sample preparation and general principles for qualitative and quantitative analysis of mineralogical phase composition. Quantitative determination of α-Si3N4, β-Si3N4, AlN, aluminium metal, Al4C3, silicon metal, boron carbide and BN are described. The problems encountered with some determinations are highlighted. Additional reduced species present in some refractories could include Al2O3⋅AlN solid solutions (so called Alons), Si3N4⋅SiO2 solid solutions and Si3N4⋅Al2O3 solid solutions (Sialons). The presence of some of these solid solution components will cause problems with both identification and quantification as they are not well-defined structures. NOTE For rationalisation of nitrogen containing phases, the total nitrogen content, analysed in accordance with EN 12698-1 is used.

This document specifies the principle, equipment, test pieces, procedures, result expression and test report of test methods for thermal shock resistance of refractories. Three test methods are included in this document. Each one is applicable to a different product type and their test results are not comparable. The test method, the test temperature and the test condition are intended to be negotiated by corresponding parties. This document does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

This document specifies a method for determining the dynamic Young's modulus of rectangular cross-section bars and circular cross-section specimens of refractories by impulse excitation of vibration at elevated temperature. The dynamic Young's modulus is determined using the resonant frequency of the specimen in its flexural mode of vibration. This document does not address the safety issues associated with its use. It is responsibility of the users of this standard to establish appropriate safety and health practices.

This document specifies requirements for the preparation of fused beads for the chemical analysis of silicon carbide containing samples using X-ray fluorescence (XRF). The test methods described in this document are for silicon carbide and silicon carbide materials; however, the principles described can be applied to other reduced materials such as boron carbide, boron nitride, ferroalloys, sialons and silicon nitride using the modifications given in Annex A. Fused cast beads of the samples prepared in accordance with this document are analysed in accordance with ISO 12677.

ISO 18886:2016 specifies the procedures for the preparation of test pieces from refractory materials by wet gunning at ambient temperatures. The test pieces are for the determination of properties on wet-gunned products prepared under either "standard conditions" (as required for quality assurance or product development) or "site conditions". In the case of "site conditions", the purpose of the testing is to establish the properties pertaining to a given installation or a given set of installation conditions. In this case, the gunned panel is obtained during the on-site installation. Such parameters as activator addition (type, amount, method of addition), conveying pressure and curing conditions (temperature, orientation of the panel) applying during the preparation of the panel are as near as possible to the same parameters pertaining to the site installation. This procedure applies to refractory materials that can be transported through a gunning hose after having been mixed with the total water requirement for material placement. The consistency of these materials (see 7.5) is typically such that they would be suitable for placement by casting were they not to be transported through the gunning hose and applied by spraying. Refractory materials that are pneumatically conveyed in the "dry" state through a gunning hose, even after mixing with a portion of the total water requirement (the bulk of the water being added at the nozzle) are dealt with in ISO 20182. ISO 18886:2016 does not apply to the gunning of plastic refractory materials (refer to ISO 1927‑1).

ISO 22016:2015 specifies methods for the wet chemical analysis of refractory products and their raw materials with below 5 % (mass percentage) sulfur.

ISO 16349:2015 specifies a method for determination of abrasion resistance of shaped and unshaped refractory materials at elevated temperature. The test temperature is not intended to exceed 1 300 °C.

ISO 10081-4:2014 specifies the classification and designation of dense shaped refractory products of special composition including oxide products, oxide and non-oxide products, non-oxide silicon carbide or carbon-based products, and further special products which are only designated but not classified, for example non-oxide products, such as boride, nitride or further combinations of the series given above.

ISO 16835:2014 specifies test methods for the thermal expansion of refractory products. It describes a method for determining the linear thermal expansion percentage, the linear thermal expansion curve, and the linear thermal expansion coefficient. ISO 16835:2014 includes the following three test methods for the thermal expansion of refractory products: a) a contact method with a cylindrical test piece; b) a contact method with a rod test piece; c) a non-contact method.

ISO 16334:2013 specifies a method for determining the resistance to explosive spalling of monolithic refractories.

ISO 14720-1:2013 defines a method for the determination of sulfur in powdered and granular non-oxidic ceramic raw materials and materials, such as silicon carbides, silicon nitrides, graphites, carbon blacks, cokes, carbon powders. If proved by the recovery rate, this method can also be applied for other non-metallic powdered and granular materials, e.g. silicon dioxide. ISO 14720-1:2013 is applicable for materials with mass fractions of sulfur from 0,005 % to 2 %. ISO 14720-1:2013 can also be applied for materials with higher mass fractions of sulfur after verification of the particular case.

This part of ISO 14720 defines a method for the determination of sulfur in powdered and granular non-oxidic ceramic raw materials and materials, which are completely oxidized at a higher temperature in an oxygen atmosphere, e.g. carbon and graphite materials. For materials which are not completely oxidizable under these conditions, it is possible to determine sulfur that can be released under these conditions, e.g. the adherent sulfur. This part of ISO 14720 is applicable for materials with mass fractions of sulfur ≤ 10 % and mass fractions of ash For the lower detection limit of this method, a mass fraction of sulfur of 0,5 mg/kg in the case of inductively coupled plasma optical emission spectrometry (ICP/OES) and 5 mg/kg in the case of ion chromatography (IC) has to be considered as a recommended value.

ISO 5017:2013 specifies a method for the determination of the bulk density, apparent porosity and true porosity of dense shaped refractory products.

ISO 1927-6:2012 specifies methods for the determination of properties of unshaped materials from test pieces prepared and stored according to ISO 1927-5:2012. The methods are applicable to dense and insulating castables and to ramming materials (including plastics) as defined in ISO 1927-1:2012 before and after firing.

ISO 1927-8:2012 specifies methods for the determination of the properties of unshaped refractory materials from test pieces prepared and stored in accordance with ISO 1927-5. The methods complement those described in ISO 1927-6. The methods have been adapted from standards for shaped refractory products to make them applicable to dense and insulating castables, and ramming materials as defined in ISO 1927-1, before and after firing.

ISO 1927-5:2012 specifies methods for the preparation and treatment (curing, drying and firing) of test pieces from monolithic (unshaped) refractory materials. The methods are applicable to dense and insulating castables and to ramming materials with the four types of chemical composition defined in ISO 1927-1:2012. The dimensions of the test pieces are specified and the preparation of the mixture, compaction methods, storage and post-treatment of the test pieces are described.

ISO 1927-7:2012 specifies methods for the testing of as-delivered pre-formed shapes. It applies to shapes fabricated from dense and insulating castables and ramming materials as defined in ISO 1927-1.

ISO 1927-4:2012 describes methods for the determination and measurement of the consistency of dense and insulating castables as defined in ISO 1927-1:2012. It is applicable to all types of dense regular castables, dense deflocculated castables and insulating castables to determine the liquid addition necessary for preparing test pieces according to ISO 1927-5:2012.

ISO 1927-3:2012 specifies the methods for the characterization of monolithic (unshaped) refractory materials as received and for checking the homogeneity of a delivery of a product. It is applicable to castables (dense and insulating), gunning materials tap hole clay, injection mixes, dry vibrating mixes, and ramming materials, as defined in ISO 1927-1.

ISO 1927-2:2012 gives guidance on the sampling of monolithic (unshaped) refractory materials for the purpose of inspection and testing for quality and general information on the reduction and treatment of samples prior to testing. It covers all materials formulated as monolithic refractory materials.

ISO 1927-1:2012 defines terms relating to monolithic (unshaped) refractory products and establishes a classification for the various types of product. Raw materials and crushed or granulated refractory materials, which do not contain any binder, are excluded.

ISO 14719:2011 specifies a spectral photometric method with 1,10-phenanthroline for the quantitative determination of Fe2+ and Fe3+ in oxidic raw and basic materials for ceramics, glass and glazes, e.g. feldspar, kaolinites, clay, limestone, quartz refractory materials. ISO 14719:2011 could be extended to other aluminosilicate materials, providing that uncertainty data is produced to support it. However, there might be problems in the decomposition of high-purity alumina and chrome ore samples. The method is not suitable for reduced materials, such as silicon carbide, graphite-magnesia, etc.

ISO 12677:2011 specifies a method for the chemical analysis of refractory and technical ceramic raw materials, intermediates and products, by means of the X-ray fluorescence (XRF) fused cast-bead method. Typical materials that can be analysed by ISO 12677:2011 are given in Clause 3. ISO 12677:2011 is not applicable to non-oxide materials, such as silicon carbides or nitrides, etc. The method is applicable to a wide range of materials containing a wide range of elements.

ISO/TR 21828:2010 gives guidance on the International Standards and national standards which apply to the testing of unshaped refractory materials, including, but not limited to, sampling, forming, obtaining test specimens or pieces and physical testing.

This part of ISO 8894 describes the hot-wire methods (“cross-array” and “resistance thermometer”) for the determination of the thermal conductivity of non-carbonaceous, dielectric refractory products and materials. This methods are applicable to dense and insulating refractories (shaped products, refractory castables, plastic refractories, ramming mixes, powdered or granular materials) with thermal conductivity values less than 1,5 W/m×K (“cross-array”) and less than 15 W/m×K (“resistance thermometer”) and thermal diffusivity values less than 5 x 10-6 m2/s.

ISO 20565-2:2008 specifies traditional (“wet process”) methods for the chemical analysis of chrome-bearing refractory products and raw materials.

ISO 20565-3:2008 specifies flame atomic absorption spectrometry (FAAS) and inductively coupled plasma atomic emission spectrometry (ICP-AES) methods for the chemical analysis of chrome-bearing refractory products and chrome-bearing raw materials.

ISO 20565-1:2008 specifies methods for the chemical analysis of chrome-bearing refractory products and chrome-bearing raw materials, using traditional (“wet”) methods, ICP-AES spectrometry and FAAS spectrometry. It covers apparatus, reagents, dissolution and determination of gravimetric silica.

ISO 10058-3:2008 specifies atomic absorption spectrometry (AAS) and inductively coupled plasma atomic emission spectrometry (ICP-AES) methods for the chemical analysis of magnesite and dolomite refractory products and raw materials.

ISO 10058-1:2008 specifies apparatus, reagents, dissolution and gravimetric silica analysis for the chemical analysis of magnesite and dolomite refractory products and raw materials.

ISO 10058-2:2008 specifies traditional (“wet process”) methods for the chemical analysis of magnesite and dolomite refractory products and raw materials.

ISO 21068-1:2008 gives definitions and specifies techniques for the preparation of samples for the chemical analysis of silicon-carbide-containing raw materials and refractory products.

ISO 21068-2:2008 specifies analytical techniques for the determination of change in mass by thermal treatment at specified temperatures, and methods for the determination of the total carbon content, free carbon, silicon carbide, silicon, total silica and free silica content of silicon-carbide-containing raw materials and refractory products.

ISO 21068-3:2008 specifies methods for the determination of total nitrogen and nitrogen calculated as silicon nitride, total oxygen, and free metallic and oxidic components in silicon carbide raw materials and refractory products. It applies only to silicon carbide materials that are not bonded with nitrogen. Nitride-bonded silicon carbide refractories are covered in EN 12698-1.

ISO 21079-3:2008 specifies flame atomic absorption spectrophotometry (FAAS) and inductively coupled plasma emission spectrometry (ICP-AES) methods for the analysis of AZS (alumina, zirconia, and silica) refractory products (containing 5 % to 45 % of ZrO2) and raw materials. ISO 21079-3:2008 is not applicable to MgO-based refractories. ISO 21079-3:2008 gives alternatives to the X-ray fluorescence (XRF) method given in ISO 12677.

ISO 21079-1:2008 specifies methods for the chemical analysis of AZS (alumina, zirconia, and silica) refractory products (containing 5 % to 45 % of ZrO2) and raw materials, using traditional ("wet") methods, inductively coupled plasma atomic emission (ICP-AE) spectrometry and flame atomic absorption (FAA) spectrometry. It covers apparatus, reagents and dissolution methods. ISO 21079-1:2008 is not applicable to MgO-based refractories. ISO 21079-1:2008 gives alternatives to the X-ray fluorescence (XRF) method given in ISO 12677.

ISO 21079-2:2008 specifies methods for the chemical analysis of AZS (alumina, zirconia, and silica) refractory products (containing 5 % to 45 % of ZrO2) and raw materials, using traditional ("wet") methods. ISO 21079-2:2008 is not applicable to MgO-based refractories. ISO 21079-2:2008 gives alternatives to the X-ray fluorescence (XRF) method given in ISO 12677.

ISO 26845:2008 specifies apparatus, reagents, sampling, sample preparation, terms and definitions, basic procedures, loss on ignition and reporting of results applicable to the following standards, which are used for the chemical analysis of refractory products and raw materials by wet chemical, AAS and ICP-AES: ISO 10058-1, ISO 10058-2 and ISO 10058-3; ISO 20565-1, ISO 20565-2 and ISO 20565-3; ISO 21079-1, ISO 21079-2 and ISO 21079-3; ISO 21587-1, ISO 21587-2 and ISO 21587-3.

ISO 20182:2008 describes the procedure for the preparation of test panels from refractory materials by gunning through pneumatic-nozzle mixing type guns at ambient temperatures. ISO 20182:2008 does not apply to plastic gunning mixes, and might not apply to those mixes that contain aggregates that are susceptible to hydration. It also does not apply to shotcrete type mixes.

ISO 21078-1:2008 specifies methods of determining boron(III) oxide in refractory products and raw materials, in mass fractions of 0,01 % or greater. It is applicable to the determination of total boron(111) oxide in oxidic materials for ceramics, glass and glazes.

ISO 8894-2:2007 describes a hot-wire (parallel) method for the determination of the thermal conductivity of refractory products and materials.

ISO 16282:2007 specifies a method intended primarily for the determination of the abrasion resistance of shaped refractory materials at ambient temperature. It can also be used for unshaped refractory materials. It provides an indication of the suitability of the material for service in abrasive or erosive conditions.

ISO 1893:2007 specifies a method for determining the deformation of dense and insulating shaped refractory products, when subjected to a constant load under conditions of progressively rising temperature (or refractoriness under load), by a differential method. The test may be carried out up to a maximum temperature of 1700 °C.

ISO 12677-3:2007 specifies inductively coupled plasma/atomic emission (ICP/AE) spectrometry and flame atomic absorption (FAA) spectrometry methods for the chemical analysis of aluminosilicate refractory products and raw materials. The methods are applicable to the determination of the following: silicon(IV) oxide (SiO2) aluminium oxide (Al2O3) iron(III) oxide (total iron oxide calculated as Fe2O3) titanium(IV) oxide (TiO2) manganese(II) oxide (MnO) calcium oxide (CaO) magnesium oxide (MgO) sodium oxide (Na2O) potassium oxide (K2O) chromium(III) oxide (Cr2O3) zirconium oxide (ZrO2) phosphorous(V) oxide (P2O5) This part of ISO 12677 gives alternatives to the X-ray flluorescence (XRF) method given in ISO 12677:2003

ISO 12677-2:2007 specifies traditional ("wet") methods for the chemical analysis of aluminosilicate refractory products and raw materials. The methods are applicable to the determination of the following: silicon(IV) oxide (SiO2) aluminium oxide (Al2O3) iron(III) oxide (total iron oxide calculated as Fe2O3) titanium(IV) oxide (TiO2) manganese(II) oxide (MnO) calcium oxide (CaO) magnesium oxide (MgO) sodium oxide (Na2O) potassium oxide (K2O) chromium(III) oxide (Cr2O3) zirconium oxide (ZrO2) phosphorous(V) oxide (P2O5) This part of ISO 12677 gives alternatives to the X-ray fluorescence (XRF) method given in ISO 12677:2003.

ISO 21587-1:2007 specifies reagents, dissolution and gravimetric silica analysis for the chemical analysis of aluminosilicate refractory products and raw materials. ISO 21587-1:2007 gives alternatives to the X-ray fluorescence (XRF) method given in ISO 12677:2003.

ISO 21078-2:2006 specifies procedures of chemical analysis for the determination of boron(III) oxide used as a binder component added to aluminosilicate refractories, using an acid extraction method. It is applicable for refractories containing less than 1 % (mass fraction) of boron(III) oxide.