This test method is designed to produce inplane shear property data for material specifications, research and development, quality assurance, and structural design and analysis. Factors that influence the inplane shear response and should therefore be reported are material, method of material preparation, specimen preparation, specimen conditioning, environment of testing, specimen alignment and gripping, speed of testing, void content, and fiber volume fraction. Properties, in the test direction, that may be obtained from this test method are as follows:

5.1.1 Inplane Shear Strength, τ₁₂^u,

5.1.2 Inplane Shear Strain at Failure, γ₁₂^u , and

5.1.3 Inplane Shear Modulus, G₁₂.

1.1 This test method determines the inplane shear properties of wound polymer matrix composites reinforced by high-modulus continuous fibers. It describes testing of hoop wound (90°) cylinders in torsion for determination of inplane shear properties.

1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the text the inch-pound units are shown in brackets. The values stated in each system are not exact equivalents; therefore, each system must be used independently of the other. Combining values from the two systems may result in nonconformance with the test method.

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