Overview - ISO 14737:2021 (Carbon and low alloy cast steels)
ISO 14737:2021 specifies requirements for carbon and low alloy cast steel grades for general applications. The third edition defines chemical compositions and recommended mechanical-property ranges for a wide set of cast-steel grade designations (for example GE200, GS200, GS340, G20NiCrMo2–2 and others), and provides informative guidance on welding and cross-references to similar UNS cast grades. The standard is intended to support consistent selection, supply and testing of steel castings for general engineering use.
Key topics and technical requirements
- Chemical composition: Defined mass-fraction limits for carbon, silicon, manganese, phosphorus, sulfur and alloying elements (Cr, Mo, Ni, V, Cu) are given in tabulated form (Table 1). Some grades include element-sum limits to align with related standards.
- Mechanical properties: Informative mechanical-property ranges (tensile strength, yield, elongation, Charpy impact energy) and typical thickness dependencies are provided (Table 2). Values are for room temperature and include guidance on test block thickness.
- Heat treatment: Heat-treatment options (normalizing, quench & temper, normalize & temper) are described; the type and parameters are usually for agreement between purchaser and manufacturer. Some heat-treatment details in Table 2 are non-mandatory information.
- Test methods and quality: Tensile and impact tests are to be performed per ISO 6892‑1 and ISO 148‑1 respectively. General delivery conditions, supplementary requirements and marking refer to ISO 4990.
- Welding guidance and UNS mapping: Annex A supplies guidance data for preheat, interpass and post‑weld heat treatment. Annex B lists UNS cast grades similar to ISO grade designations (not necessarily exact equivalents).
Applications and who uses ISO 14737
ISO 14737 is used by:
- Foundries and steel casters for specifying cast-steel grades and verifying chemical controls.
- Materials and design engineers selecting cast-steel grades for general engineering components (e.g., housings, machine parts and general-purpose castings).
- Procurement/specification authors who require standard grade designations and test/marking requirements.
- Quality, inspection and testing laboratories that perform tensile and Charpy testing to the referenced ISO methods.
- Welding engineers who need guidance on preheat, interpass temperatures and post-weld heat treatment for cast steels.
Keywords: ISO 14737:2021, carbon and low alloy cast steels, cast steel grades, chemical composition, mechanical properties, heat treatment, welding guidance, ISO 4990, ISO 6892-1, ISO 148-1.
Related standards
- ISO 4990 - Steel castings: general technical delivery requirements (delivery, marking, supplementary requirements)
- ISO 6892‑1 - Tensile testing of metallic materials
- ISO 148‑1 - Charpy pendulum impact test
- EN 10027 - Steel designation systems (referenced for naming/numbering)
