Overview
EN ISO 14574:2025 - Fine ceramics (advanced ceramics) - specifies procedures for determining the tensile behaviour of ceramic matrix composite (CMC) materials at elevated temperature. The standard covers testing in air, vacuum and inert gas atmospheres for continuous fibre‑reinforced CMCs (uni‑directional 1D, bi‑directional 2D, multi‑directional xD with x>2) and includes carbon‑fibre‑reinforced carbon matrix (C/C) materials. It replaces the 2016 edition and reflects ISO/CEN agreement for harmonized high‑temperature tensile testing of advanced technical ceramics.
Key Topics
- Scope & specimen types: Applies to 1D, 2D and xD CMCs tested along principal or off‑axis directions; includes C/C composites. Notes typical use of anti‑oxidation coatings for materials used in air.
- Test principle: Controlled tensile loading at elevated temperatures with repeatable atmosphere control, strain measurement and temperature calibration.
- Apparatus & instrumentation: Requirements for test machines, load trains, high‑temperature chambers, heating setups, strain measurement (strain gauges, high‑temperature extensometers), temperature sensors and data acquisition.
- Specimen preparation: Machining, dimensional measurement and recommended specimen geometries commonly used for CMC tensile tests.
- Test procedures: Temperature zone control, calibration methods (including use of thermocouples or cartographic specimens), atmosphere control (air/vacuum/inert), displacement/strain rates, specimen mounting and extensometer set‑up.
- Data & calculations: Determination of tensile strength, strain at maximum force, tensile modulus (linear and non‑linear methods), test validity criteria, uncertainty considerations.
- Reporting: Required test report content to ensure reproducibility and comparability of high‑temperature tensile results.
Applications
EN ISO 14574:2025 is used by:
- Materials engineers and R&D laboratories developing advanced ceramics and ceramic matrix composites.
- Quality and testing laboratories performing high‑temperature mechanical characterization for aerospace, power generation (gas turbines), automotive braking systems, industrial furnaces, and nuclear/hot‑structure components.
- Manufacturers validating material performance, coatings (anti‑oxidation), and component design inputs where tensile properties at elevated temperatures are critical.
Using this standard ensures consistent, comparable tensile property data for design, certification and material selection of high‑temperature ceramic composites.
Related Standards (if applicable)
- ISO 14574:2025 is issued by ISO/TC 206 in collaboration with CEN/TC 184 and is the endorsed European standard EN ISO 14574:2025. For adjacent test methods and complementary mechanical property standards, consult other ISO/CEN documents on ceramic testing and high‑temperature materials characterization.
