ISO/TC 25 - Cast irons and pig irons

This document defines the grades and the corresponding requirements for ausferritic spheroidal graphite cast irons. This document specifies five grades of ausferritic spheroidal graphite cast iron by a classification based on mechanical properties determined on machined test pieces prepared from: — separately cast samples, side-by-side cast or cast-on samples; — samples cut from a casting. This document also specifies two grades by a classification as a function of hardness.

1 Scope This document specifies the properties of unalloyed and low-alloyed grey cast irons used for castings that have been manufactured in sand moulds or in moulds with comparable thermal behaviour. This document specifies the characterizing properties of grey cast irons by any of the following: a) the tensile strength of cast samples; b) if agreed by the manufacturer and the purchaser, the tensile strength of samples cut from a casting; c) if agreed between the manufacturer and the purchaser, the hardness of the material determined on castings or on a cast-on knob. If agreed by the manufacturer and the purchaser, the combination of tensile strength from option a) or option b) and plus hardness from option c) can be specified. Information on specifying a combination of tensile strength and hardness is given in Annex B. This document specifies eight grades of grey cast iron according to tensile strength (see Table 1) and six grades of grey cast iron according to Brinell hardness (see Table 2). This document does not apply to grey cast irons used for pipes and pipe fittings and continuous cast products. This document does not cover technical delivery conditions for grey iron castings. NOTE General information on the engineering properties of grey cast irons is provided in ISO/TR 10809-1.

This document specifies a method of classifying the microstructure of graphite in cast irons by comparative visual analysis. The purpose of this document is to provide information about the method of graphite classification. It is not intended to give information on the suitability of cast-iron types and grades for any particular application. The particular material grades are specified mainly by mechanical properties and, in the case of austenitic and abrasion resistant cast irons, by their chemical composition. The interpretation of graphite form and size does not allow a statistically valid statement on the fulfilment of the requirements specified in the relevant material standard.

This document specifies a test method for evaluating nodularity in spheroidal graphite cast irons by comparative visual analysis and image analysis techniques. This document provides figures for different levels of nodularity and graphite particle count of spheroidal graphite cast irons for visual analysis.

This document defines the grades and the corresponding requirements for spheroidal graphite cast irons. This document specifies two groups of spheroidal graphite cast iron grades by a classification based on mechanical properties measured on machined test pieces prepared from cast samples. The first group deals mainly with ferritic to pearlitic grades. The second group deals with solid-solution strengthened ferritic grades. This document also gives an informative classification as a function of hardness. This document does not apply to the following: — spheroidal graphite cast irons used for pipes, fittings and accessories which are specified in accordance with ISO 2531 and ISO 7186; — highly alloyed (austenitic) spheroidal cast irons which are specified in accordance with ISO 2892; — ausferritic cast irons which are specified in accordance with ISO 17804.

ISO 16112:2016 specifies five grades of compacted (vermicular) graphite cast irons. ISO 16112:2016 specifies five grades based on the minimum mechanical properties measured on machined test pieces prepared from - separately cast samples, - side-by-side cast samples, - cast-on samples, or - samples cut from a casting.

ISO/TR 945-3:2016 gives the designations, descriptions and reference micrographs of the matrix structures of cast irons. It applies to the following types of cast irons: - grey cast irons (Table 4.1); - spheroidal graphite cast irons (Table 4.2); - austenitic cast irons (Table 4.3); - malleable cast irons (Table 4.4); - compacted (vermicular) graphite cast irons (Table 4.5); - ausferritic spheroidal graphite cast irons (Table 4.6); - abrasion-resistant cast irons (Table 4.7). Each matrix structure is defined with explanations and micrographs. Unless otherwise stated in Clause 4, the micrographs shown correspond to samples etched with a solution of 2 % nitric acid in ethanol (Nital).

The purpose of ISO/TR 10809-2:2011 is to assist the design engineer to understand and to acquire knowledge of how the family of cast iron materials can be welded and to utilize this technology to its full advantage in selecting the most appropriate technique for a particular cast iron. Because the application of welding technology and the metallurgical implications of welding are not scientific disciplines normally taught to engineering students, such users often have limited knowledge of the fundamentals underpinning welding technology for cast irons. ISO/TR 10809-2:2011 explains what can be achieved, what cannot be achieved and why. It is not designed to be a textbook of welding technology. It helps users to select the most appropriate welding process and conditions for a specific application. ISO/TR 10809-2:2011 covers production (including finishing and joint welding) and repair welding.

ISO/TR 945-2:2011 deals with the two-dimensional characterisation of graphite form and size in cast irons. A standard method for determining graphite form by image analysis had not been developed at the time of this report, but several methods are in use in the industry. The purpose of ISO/TR 945-2 is to give an illustration of what is possible and to suggest ways in which the technique might develop in the future. ISO/TR 945-2:2011 does not apply to the graphite distribution of grey (lamellar graphite) cast iron as defined in ISO 945-1. ISO/TR 945-2:2011 describes procedures used to carry out image analysis of graphite form and size and provides a method of comparison to the results obtained using visual analysis techniques. It does not specify any particular mathematical description of the graphite forms but provides a means for comparison.

The purpose of ISO/TR 10809-1:2009 is to assist the designer and engineer in understanding the family of cast iron materials and to utilize them with a more complete knowledge of their potential, among the wide range of other engineering materials and fabrication methods now available. A considerable amount of the data provided is metallurgical, but it is usually the metallurgical aspects of the cast irons that create misunderstandings when these materials are specified. This is because metallurgy is not one of the scientific disciplines taught to engineering students. Thus, such students often have a lack of knowledge regarding the fundamentals underpinning the material properties of cast irons. ISO/TR 10809-1:2009 suggests what can be achieved, what cannot be achieved and why, if and when cast irons are specified. It is not designed to be a textbook of metallurgy. It is intended to help people to choose the correct material for the right reasons and also to help to obviate the specification or expectation of unrealistic additional requirements, which are unlikely to be met and which can be detrimental to the intended application.

ISO 2892:2007 specifies the grades of austenitic cast irons in terms of graphite form and matrix structure: either flake (lamellar) or spheroidal graphite in an austenitic matrix, chemical composition: as given for each of the grades, and mechanical properties obtained from separately cast samples.

ISO 21988:2006 defines the grades of abrasion-resistant white cast irons. It specifies the grades in terms of chemical composition and hardness. The types of abrasion-resistant white cast irons covered are unalloyed or low alloy cast irons, nickel-chromium cast irons and high chromium cast irons.

ISO 5922:2005 specifies requirements for two types of malleable cast iron, namely whiteheart malleable cast iron and blackheart malleable cast iron, used in the manufacture of castings. Classification is given for each type of malleable cast iron on the basis of mechanical properties determined on separately cast test pieces. ISO 5922:2005 is applicable only to malleable cast iron cast into sand moulds or moulds of comparable thermal diffusivity.

ISO/TR 15931:2004 is intended to achieve the following: to make the designation of cast irons and pig irons as simple and as understandable as possible, bearing in mind language barriers world-wide; to define cast iron and pig iron designations by a simple code consisting of relevant letters and numbers only; to ensure that the agreed system is user-friendly from the point of view of the casting designer, the manufacturer (founder) and the user; to ensure that the designation system clearly defines the materials described by standards and details all of the important attributes of mechanical properties, chemical composition and additional features that need to be described.

Defines pig-irons and the subdivision of pig-irons into different classes. An annex gives sampling and preparation of samples intended for the determination of the chemical composition of pig-irons.

This document specifies the properties of unalloyed and low-alloyed grey cast irons used for castings that have been manufactured in sand moulds or in moulds with comparable thermal behaviour. This document specifies the characterizing properties of grey cast irons by any of the following: a) the tensile strength of cast samples; b) if agreed by the manufacturer and the purchaser, the tensile strength of samples cut from a casting; c) if agreed between the manufacturer and the purchaser, the hardness of the material determined on castings or on a cast-on knob. If agreed by the manufacturer and the purchaser, the combination of tensile strength from option a) or option b) and plus hardness from option c) can be specified. Information on specifying a combination of tensile strength and hardness is given in Annex B. This document specifies eight grades of grey cast iron according to tensile strength (see Table 1) and six grades of grey cast iron according to Brinell hardness (see Table 2). This document does not apply to grey cast irons used for pipes and pipe fittings and continuous cast products. This document does not cover technical delivery conditions for grey iron castings. NOTE General information on the engineering properties of grey cast irons is provided in ISO/TR 10809-1.

ISO 945-1:2017 specifies a method of classifying the microstructure of graphite in cast irons by comparative visual analysis. The purpose of this document is to provide information about the method of graphite classification. It is not intended to give information on the suitability of cast-iron types and grades for any particular application. The particular material grades are specified mainly by mechanical properties and, in the case of austenitic and abrasion resistant cast irons, by their chemical composition. The interpretation of graphite form and size does not allow a statistically valid statement on the fulfilment of the requirements specified in the relevant material standard.

ISO 945-1:2008 specifies a method of classifying the microstructure of graphite in cast irons by comparative visual analysis. The purpose of this part of ISO 945 is to provide information about the method of graphite classification. It is not intended to give information on the suitability of cast-iron types and grades for any particular application. The particular material grade is specified by results from tensile tests or hardness testing and, in the case of austenitic cast irons, by their chemical composition. The interpretation of graphite form and size does not allow a statistically valid statement on the fulfilment of the requirements specified in the relevant material standard. The structure of the metallic matrix (e.g. ferrite, pearlite) has a significant effect on the material properties. Such an interpretation is not the purpose of this part of ISO 945.

ISO 16112:2006 specifies five grades of compacted (vermicular) graphite cast irons. ISO 16112:2006 specifies five grades based on the minimum mechanical properties measured on machined test pieces prepared from separately cast samples, cast-on samples, or samples cut from a casting.

ISO 17804:2005 defines the grades and the corresponding requirements for ausferritic spheroidal graphite cast irons. ISO 17804:2005 specifies five grades of ausferritic spheroidal graphite cast iron by a classification based on mechanical properties measured on machined test pieces prepared from separately cast samples or cast-on samples, and samples cut from a casting. ISO 17804:2005 also specifies two grades by a classification as a function of hardness.

ISO 185:2005 specifies the properties of unalloyed and low-alloyed grey cast irons used for castings, which have been manufactured in sand moulds or in moulds with comparable thermal behaviour. ISO 185:2005 specifies the characterizing properties of grey cast iron by either the tensile strength of separately cast samples, or if agreed by the manufacturer and the purchaser, of cast-on samples or samples cut from a casting, or if agreed between the manufacturer and the purchaser, the hardness of the material measured on castings or on a cast-on knob.

ISO 1083:2004 defines the grades and the corresponding requirements for spheroidal graphite cast irons. It specifies a classification based on mechanical properties measured on machined test pieces prepared either from: separately cast samples; cast-on samples; samples cut from a casting. ISO 1083:2004 also specifies a classification as a function of hardness. It does not apply to spheroidal graphite cast iron used for pipes, fittings and accessories nor to highly alloyed (austenitic) spheroidal cast irons or to ausferritic cast irons.

Cancels and replaces the ISO Recommendation R 185:1961. Applies only to grey cast iron, cast in sand moulds or moulds of comparable thermal diffusivity. The classification comprises six grades based on the tensile properties of test pieces machined from separately cast test samples. Cast-on samples may be used in cases where greater castings are to be tested. Annex A gives a classification as a function of hardness.

This second edition cancels and replaces the first edition (ISO 1083:1976), in which only six grades of spheroidal graphite cast iron were defined. Defines nine grades of spheroidal graphite cast iron and their classification in two distinct categories (separately cast test samples and cast-on test samples, respectively). An annex gives a classification as a function of hardness.

Cancels and replaces ISO Recommendations R 942:1969, R 943:1969 and R 944:1969. Specifies requirements for malleable cast iron and gives a classification on the basis of mechanical properties. An annex gives classification principles.

This method of designating the microstructure of graphite is not intended as a basis for acceptance specifications. Specifies general, sampling, microscopic examination, reference diagramms, designation of graphite by form, distribution and size.

Specifies requirements for the determination of the impact strength. The test consists in breaking a series of unnotched machined cylindrical test pieces resting freely between supports, and measuring the difference between the kinetic energy of the hammer before and after fracture of the test piece. Annex A includes non-standard test pieces, annex B includes notes on coefficients for calculation of impact strength.

Relates to nine grades of flake graphite austenitic cast iron and eleven grades of spheroidal or nodular graphite austenitic cast iron intended for subsequent use in the manufacture of castings. These grades of material are based on chemical composition and mechanical properties. Specifies symbols, production, properties and applications, sampling, test samples, testing and retests. An informative annex gives supplementary data on mechanical and physical properties and typical applications.