1.1 These test methods cover the specimen, apparatus, and procedures for the determination of the constant-amplitude tension-tension fatigue properties of resin matrix composites reinforced by oriented continuous or discontinuous high modulus > 3 X 10 psi (> 20 GPa) fibers. This includes only the following:

1.1.1 Unidirectional -Continuous or discontinuous reinforcing fibers, 0° and 90° properties.

1.1.2 Laminates of Symmetric, Orthotropic Construction -Continuous or discontinuous reinforcing fibers.

1.2 The two methods are as follows:

1.2.1 Method A -A system in which the load is controlled so that the test specimen is subjected to a constant amplitude of load in each cycle.

1.2.2 Method B -A system in which the strain or deformation is controlled so that the test specimen is subjected to a constant amplitude of strain in each cycle.

1.3 The values stated in inch-pound units shall be regarded as the standard. The values in parentheses are for information only.

1.4 This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety problems 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.