ASTM D6671/D6671M
Scope
1.1 This test method covers the determination of interlaminar fracture toughness, Gc, of continuous fiber-reinforced composite materials at various Mode I to Mode II loading ratios using the
Mixed-Mode Bending (MMB) Test.
1.2 This test method is limited to use with composites consisting of unidirectional carbon fiber tape laminates with brittle and tough single-phase polymer
matrices. This test method is further limited to the determination of fracture toughness as it initiates from a delamination insert. This limited scope reflects the experience gained in round
robin testing. This test method may prove useful for other types of toughness values and for other classes of composite materials; however, certain interferences have been noted (see Section
6). This test method has been successfully used to test the toughness of both glass fiber composites and adhesive joints.
1.3 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. The
values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the
two systems shall not be combined.
1.4 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.
1.5 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.
Keywords
composite materials; delamination; interlaminar fracture toughness; mixed-mode bending; Mode I–Mode II;
ICS Code
ICS Number Code 19.060 (Mechanical testing)
DOI: 10.1520/D6671_D6671M-22