ISO/TR 15931:2004

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:

• ISO 185 (grey cast irons), ISO 1083 (spheroidal graphite), ISO 5922 (malleable), ISO 2892 (austenitic), ISO 9147 (pig irons), ISO 16112 (vermicular), ISO 17804 (ausferritic), ISO 21988 (abrasion resistant), and ISO/TR 7003 (designation guidance).

Keywords: ISO/TR 15931:2004, designation system, cast irons, pig irons, material designation, graphite structure, mechanical properties, chemical composition, ISO standards.