ASTM D 5026:2023

1.1 This test method outlines the use of dynamic mechanical instrumentation for gathering and reporting the viscoelastic properties of thermoplastic and thermosetting resins and composite systems in the form of rectangular specimens molded directly or cut from sheets, plates, or molded shapes. The tensile data generated is used to identify the thermomechanical properties of a plastic material or composition using a variety of dynamic mechanical instruments. 1.2 This test method is intended to provide a means for determining viscoelastic properties of a wide variety of plastic materials using nonresonant forced-vibration techniques, in accordance with Practice D4065 . Plots of the elastic (storage) modulus; loss (viscous) modulus; complex modulus and tan delta as a function of frequency, time, or temperature are indicative of significant transitions in the thermomechanical performance of the polymeric material system. 1.3 This test method is valid for a wide range of frequencies, typically from 0.01 Hz to 100 Hz. 1.4 Due to possible instrumentation compliance, the data generated are intended to indicate relative and not necessarily absolute property values. 1.5 Test data obtained by this test method are relevant and appropriate for use in engineering design. 1.6 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only. 1.7 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. Note 1: This test method is technically equivalent to ISO 6721, Part 4. 1.8 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.

83.080.01