EN ISO 2566-1:2021 PDF

Overview

EN ISO 2566-1:2021 (ISO 2566-1:2021, corrected 2022-06) specifies a method for converting room-temperature percentage elongation after fracture measured on one gauge length to an equivalent value on another gauge length for carbon and low-alloy steels. Conversions are based on the Oliver formula (presented as Formula (1) in the standard) and are provided as conversion factors, tables and figures to support tensile-test result comparisons and contract acceptance.

Keywords: EN ISO 2566-1:2021, steel elongation conversions, gauge length conversion, Oliver formula, tensile testing, carbon steels.

Key Topics

• Scope and applicability
  • Applies to carbon, carbon‑manganese, molybdenum and chromium‑molybdenum steels in the tensile strength range 300 N/mm² to 700 N/mm².
  • Valid for hot‑rolled, hot‑rolled and normalized, or annealed conditions (with or without tempering).
  • Not applicable to cold‑reduced steels, quenched‑and‑tempered steels, or austenitic steels.
  • Conversions are not appropriate where the gauge length exceeds 25·√S0 (standard notation in the document) or where the test-piece width/thickness ratio > 20.
• Conversion basis
  • Uses the Oliver formula (Formula (1)) as the mathematical basis; the standard gives simplified formulae and conversion tables derived from it.
  • Supports conversions between proportional gauge lengths (k·√S0 - e.g., k = 4, 5.65, 8.16, 11.3), and non‑proportional (fixed) gauge lengths (e.g., 50, 80, 100, 200 mm).
  • Includes direct multiplication factors, detailed tables (Tables 1–21) and figures (Figures 1–5) for common conversions.
• Use and limitations
  • Conversions intended for acceptance purposes only by agreement between supplier and customer.
  • In disputes, the elongation must be measured on the gauge length specified in the contract/specification.

Applications

• Quality control and acceptance testing in steel production and processing.
• Converting historical or supplier test results to a contractually required gauge length without re-testing.
• Mechanical testing laboratories, metallurgists, inspection bodies and design engineers who compare percentage elongations across different test standards or specifications.
• Useful in procurement, certification and materials compliance where elongation limits are defined on different gauge lengths.

Related standards

• ISO 2566 is a series; other parts of the ISO 2566 series address different steel groups or methods - consult the ISO website for the full list.
• Use together with relevant tensile testing standards and national/industry specifications for steel mechanical properties.

For exact formulae, conversion tables and figures, refer to the full text of EN ISO 2566-1:2021 (ISO 2566‑1:2021).