Overview
ISO 204:2023 - Metallic materials - Uniaxial creep testing in tension - Method of test - defines standardized methods for measuring time-dependent deformation (creep) and rupture of metallic materials under uniaxial tensile loading at elevated temperatures. This fourth edition (2023) replaces the 2018 version and covers uninterrupted (continuous) creep tests, interrupted (periodic) elongation tests, stress-rupture tests, and verification tests to confirm a material can survive a predetermined time under a given load.
Key topics and requirements
The standard specifies technical requirements and procedures for:
- Test types: uninterrupted creep (continuous extension monitoring), interrupted creep (periodic elongation measurement), stress rupture (time-to-fracture), and time‑verification tests.
- Apparatus: requirements for testing machines, load verification, and extensometer/extention measuring devices.
- Temperature control: heating devices, temperature measurement, permissible temperature deviations, thermocouple selection and calibration.
- Test pieces: shape, dimensions, preparation, marking of gauge and reference lengths, and determination of cross-sectional area.
- Test procedure: heating, application of test force, planned and accidental interruptions, recording of temperature and elongation/extension, and generation of elongation‑time or extension‑time curves.
- Results and reporting: determination of test results, test validity, accuracy and uncertainty estimation, and required test report content.
- Annexes: guidance on thermocouple drift and calibration, creep testing with V or blunt circumferential notches, uncertainty estimation (GUM), and representation/extrapolation of creep rupture life.
Normative references cited include ISO 6892‑1, ISO 6892‑2, ISO 7500‑2 and ISO 9513.
Applications and users
ISO 204:2023 is intended for:
- Materials testing laboratories performing high-temperature tensile creep and rupture testing.
- Design and R&D engineers in power generation, aerospace, petrochemical, and heavy industry validating long-term high-temperature performance of alloys.
- Quality assurance and certification bodies that require standardized creep data for component qualification.
- Manufacturers of high-temperature components (turbine blades, boiler tubes, pressure vessels) who need reliable creep-life data for material selection and lifetime assessment.
Using ISO 204:2023 ensures consistent, reproducible creep test data for material comparison, life prediction, and compliance with contractual or regulatory requirements.
Related standards
- ISO 6892‑1: Tensile testing at room temperature
- ISO 6892‑2: Tensile testing at elevated temperature
- ISO 7500‑2: Verification of tension creep testing machines
- ISO 9513: Calibration of extensometer systems
Keywords: ISO 204:2023, uniaxial creep testing, metallic materials, creep test, stress rupture, extensometer, thermocouple calibration, creep rupture life, measurement uncertainty.