ASTM D6671 / D6671M – 19 : Standard Test Method for Mixed Mode I-Mode II Interlaminar Fracture Toughness of Unidirectional Fiber Reinforced Polymer Matrix Composites
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.
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 .
This test method has been successfully used to test the toughness of both glass fiber composites and adhesive joints.