Overview
ISO/TR 15931:2004 - "Designation system for cast irons and pig irons" defines a simple, language‑neutral code for naming cast irons and pig irons. The Technical Report standardizes how material grades are written on drawings and orders using four structured positions (separated by a solidus “/”), so designers, foundries and users can unambiguously communicate material type, graphite and matrix structure, mechanical or chemical properties, and optional additional requirements.
Key topics and requirements
- Four-position designation format: Position 1 = relevant ISO standard number; Position 2 = code letters for base material and graphite/matrix structure; Position 3 = primary properties (mechanical or chemical); Position 4 = optional additional requirements.
- Material coding: Uses concise letter codes (e.g., JL for grey/lamellar graphite, JS for spheroidal/nodular, JV for vermicular, JY for pig iron, JMB/JMW for blackheart/whiteheart malleable iron).
- Property specification: Position 3 supports tensile strength (N/mm2), elongation (%), Brinell/Vickers/Rockwell hardness (HBW/HV/HRC), impact test indicators (LT, RT), or elemental chemical composition (element symbols and mass fractions).
- Additional qualifiers: Position 4 can denote sample position for tensile tests (S = separately cast, U = cast‑on, C = cut from casting) and modifiers like D (as‑cast), H (heat‑treated), W (weldability), Z (other order‑specific requirements).
- Format rules: Symbols separated by hyphens within positions; chemical elements use standard international symbols (e.g., Cr, Si). Example designations: ISO185/JL/200/SH, ISO1083/JS/400-18LT/U, ISO2892/JLA/XNi15Cu6Cr2/S.
- Scope & intent: Emphasis on clarity across language barriers and compatibility with existing ISO materials standards (references given).
Applications and users
- Who uses it: casting designers, foundry engineers (manufacturers/founders), procurement/specification engineers, metallurgists, quality control personnel, and standards committees.
- Practical uses:
- Specifying material requirements on engineering drawings and contracts.
- Ordering and procurement of cast iron and pig iron with unambiguous material grades.
- Quality inspection and acceptance testing by linking designations to required mechanical/chemical tests.
- Facilitating international trade and communication by using a standardized, language‑independent code.
Related standards
ISO/TR 15931:2004 is intended to be used with the specific material standards it references, for example:
Keywords: ISO/TR 15931:2004, designation system, cast irons, pig irons, material designation, graphite structure, mechanical properties, chemical composition, ISO standards.
