Overview - ISO 2892:2007 (Austenitic cast irons - Classification)
ISO 2892:2007 specifies the classification and requirements for austenitic cast irons. The standard defines material grades by graphite form (flake/lamellar or spheroidal/nodular), matrix structure (austenitic), chemical composition, and mechanical properties obtained from representative test samples. It is intended for high-alloy cast irons used where heat resistance, corrosion resistance, low-temperature performance, special physical or wear properties are required.
Key topics and technical requirements
- Grade designation and identification
- Material symbols and grade names are defined (see Tables 1–4). Designations follow ISO TR 15931 guidance.
- Graphite form and matrix
- Distinguishes flake (lamellar) and spheroidal (nodular) graphite in an austenitic matrix.
- Chemical composition
- Composition limits for engineering and special-purpose grades are given (nickel, manganese, silicon, chromium, copper, phosphorus and optional elements such as niobium or molybdenum).
- Tables specify allowable ranges for each grade.
- Mechanical properties and testing
- Tensile strength, 0.2% proof stress, elongation and Charpy impact values are prescribed and must be determined from separately cast test samples (unless otherwise agreed).
- Tensile testing is to follow ISO 6892 and Charpy impact testing is referenced (ISO 148-3).
- Sampling and test-piece production
- Guidance on sample types: separately cast samples, cast-on samples, or samples cut from castings depending on casting mass/thickness.
- Frequency of sampling is based on manufacturer QA or agreement with purchaser.
- Manufacture and heat treatment
- Production methods and heat treatments are generally at the manufacturer’s discretion unless purchaser specifies otherwise. Annex B provides typical heat treatments.
- Ordering information
- Purchasers must specify complete grade designation and any special requirements at order acceptance.
Applications and intended users
- Typical users:
- Foundries, casting engineers, material specifiers, procurement professionals, design engineers in oil & gas, chemical processing, power generation, and cryogenics.
- Typical applications:
- Components requiring corrosion resistance, heat resistance, low-temperature toughness, or specific wear/physical properties (see Annex A for grade-specific recommendations).
- Benefits:
- Ensures material interchangeability, quality verification, and suitable performance for pressure and specialty applications.
Related standards and references
- ISO 6892 - Metallic materials - Tensile testing
- ISO 148-3 (referenced) - Charpy pendulum impact test procedures
- ISO TR 15931 - Designation system for cast irons and pig irons
For specification or procurement, reference ISO 2892:2007 to select the correct austenitic cast-iron grade and to align testing, sampling and documentation with international practice.