The ASTM D5379 test determined the shear properties of composite materials reinforced with high modulus fibers. These materials are either continuous fiber or discontinuous fiber reinforced composite materials. ASTM D5379 is commonly referred to as the Iosipescu shear test.

ASTM D5379 loads the specimen through its top and bottom edges, while ASTM D7078 loads the specimen through its surface.

In order to conduct this test, the rectangular flat strip composite material sample symmetrically forms a V-shaped notch. Sample preparation (including gaps) can be completed at your factory. Strain gauges are applied to both sides of the specimen. Use special fixtures to secure the specimen and apply the load at a specified rate until failure occurs. The results can include shear stress/ultimate strength, shear strain/ultimate strain, shear string elastic modulus, and offset shear strength. Reference: ASTM D5379- Standard Method for Determining Shear Properties of Composite Materials by V-notch Beam Method.