ASTM E2769-22 - Standard Test Method for Elastic Modulus by Thermomechanical Analysis Using Three-Point Bending and Controlled Rate of Loading

1.1 This test method describes the use of linear controlled-rate-of-loading in three-point bending to determine the elastic modulus of isotropic specimens in the form of rectangular bars using a thermomechanical analyzer (TMA).

1.2 This test method provides a means for determining the elastic modulus within the linear region of the stress-strain curves (see Fig. 1). This test is conducted under isothermal temperature conditions from –100 °C to 300 °C.

FIG. 1 Stress-Strain Curve (Linear Region)

1.3 Typical test specimens are in the form of thin strips 0.5 mm in thickness, 1.5 mm in width, and 6 mm in length. The size of the test specimen is limited by the distance between the supports used in the three-point bending mode of operation, commonly 0.5 cm.

1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.