ISO 14126

ISO 14126 – HOW TO PERFORM A TEST

To perform a test in accordance with ISO 14126 entails meticulous preparation and adherence to standardized procedures. The standard outlines two distinct methods for evaluating the compressive properties:

• Method 1 – Entails shear loading of the specimen. This approach involves subjecting the specimen to compressive forces along its major axis. To execute Method 1 effectively, a specialized fixture, such as the Celanese-type fixture, is utilized. This fixture provides the necessary support for the specimen during compression.
• Method 2 – Offers flexibility by allowing for end loading or mixed loading of the specimen. While less common than Method 1, this approach accommodates different testing scenarios and requirements.

The choice between Method 1 and Method 2 hinges upon the specific objectives of the evaluation.

ISO 14126 – EQUIPMENT AND SETUP

Compliance with ISO 14126 requires the use of specific testing equipment and careful setup procedures for both methods outlined in the standard. In Method 1, the Celanese-type fixture is commonly chosen due to its widespread use and established reliability. Conversely, Method 2 necessitates fixtures capable of accommodating various loading configurations, highlighting the importance of versatile equipment selection.

Given the significant forces involved in testing, it is advisable to employ a dual-column electromechanical testing system. This system enables precise control and measurement, ensuring consistent compression at a steady displacement rate until the specimen fractures. By promoting uniformity in testing conditions, this setup enhances the reliability and accuracy of results.

Critical to the evaluation process is the accurate measurement of strain, which is essential for determining key parameters such as compressive modulus and compressive failure strain. To measure the axial strain during the test, it is essential to use extensometers or bonded resistance strain gauges.