Overview
ISO 11972:2023 - Corrosion‑resistant cast steels for general applications - specifies a set of cast‑steel grades intended for a wide range of corrosion‑resistant castings. The third edition (2023) defines chemical compositions, mechanical properties, heat‑treatment regimes and delivery conditions for alloy cast steels commonly used where corrosion resistance is required. Annex A provides informative cross‑references to similar UNS cast grade numbers.
Keywords: ISO 11972:2023, corrosion‑resistant cast steels, cast steel grades, UNS cast grades, corrosion‑resistant castings
Key topics and technical requirements
- Scope and delivery: Materials must also conform to the general delivery requirements of ISO 4990; supplementary requirements (optional for purchaser) are listed in ISO 4990.
- Chemical composition (Table 1): The standard lists mass‑fraction limits for elements (C, Si, Mn, P, S, Cr, Mo, Ni, N, Cu, Nb, W, etc.) for named grades such as GX12Cr12 (1.4011), GX2CrNi19–11 (1.4309), GX4CrNi13–4 (1.4317) and many others.
- Mechanical properties (Table 2): Specified properties at room temperature include proof or yield strength (Rp0,2), tensile strength (Rm), elongation (A) and impact energy (AV). Maximum ruling thickness and test‑block thickness limits (typically ≤150 mm) are given; impact testing is performed when required by purchaser.
- Heat treatment (Table 3): Recommended austenitizing, solution treating, tempering and quenching parameters are specified per grade (temperature ranges and cooling methods) to achieve the required microstructure and properties.
- Supplementary requirements (Clause 8): Lists optional purchaser‑specified checks and tests referenced to ISO 4990.
- Annex A (informative): Provides UNS cast grade equivalents or similar numbers for easier material selection and international procurement.
Applications
ISO 11972:2023 is targeted at cast components where corrosion resistance and reliable mechanical performance are required. Typical uses include:
- Pump and valve bodies, flanges and fittings for corrosive fluids
- Chemical process and petrochemical castings
- Marine and offshore components exposed to seawater
- General industrial equipment where alloy cast steels provide improved corrosion and mechanical performance
(Use of specific grades depends on service environment, corrosion mechanism and mechanical loads; consult the tables in the standard for grade selection.)
Who should use this standard
- Foundries and casting manufacturers specifying materials and heat treatments
- Materials, corrosion and mechanical engineers selecting cast steels
- Procurement and quality assurance professionals preparing purchase orders and inspection plans
- Designers and specifiers requiring internationally harmonized grade definitions and UNS cross‑references
Related standards
- ISO 4990 - Steel castings - General technical delivery conditions (normative reference)
- EN 10027‑1 / EN 10027‑2 - Steel designation systems (referenced in Annex A)
ISO 11972:2023 provides a practical framework for selecting and specifying corrosion‑resistant cast steels with internationally harmonized chemical, mechanical and heat‑treatment requirements.