ASTM D3479 – Test Method for Tension-Tension Fatigue of Polymer Matrix Composite Materials

ASTM D3479 Tension-Tension Fatigue of Polymer Matrix Composite Materials

ASTM D3479 – This test method determines the fatigue behavior of polymer matrix composite materials subjected to tensile cyclic loading.

The composite material forms are limited to continuous-fiber or discontinuous-fiber reinforced composites for which the elastic properties are specially orthotropic

with respect to the test direction.

This test method is limited to unnotched test specimens subjected to constant amplitude uniaxial in-plane loading where the loading is defined in terms of a test

control parameter

Significance and Use

ASTM D3479 – This test method is designed to yield tensile fatigue data for material specifications, research and development, quality assurance, and structural

design and analysis.

The primary test result is the fatigue life of the test specimen under a specific loading and environmental condition.

Replicate tests may be used to obtain a distribution of fatigue life for specific material types, laminate stacking sequences, environments, and loading conditions.

Guidance in statistical analysis of fatigue life data,

This test method can be utilized in the study of fatigue damage in a polymer matrix composite such as the occurrence of microscopic cracks, fiber fractures,

or delaminations.

The specimen’s residual strength or stiffness, or both, may change due to these damage mechanisms.

The loss in stiffness may be quantified by discontinuing cyclic loading at selected cycle intervals to obtain the quasi-static axial stress-strain curve using modulus

determination procedures found in Test Method D 3039/D 3039M.

The loss in strength associated with fatigue damage may be determined by discontinuing cyclic loading to obtain the static strength using Test Method D 3039/D 3039M

Grips –  The grips shall also have sufficient fatigue rating for loads at which testing will take place.