Standard Test Method for Compressive Residual Strength Properties of Damaged Polymer Matrix Composite Plates

Importancia y uso:

5.1 Susceptibility to damage from concentrated out-of-plane forces is one of the major design concerns of many structures made of advanced composite laminates. Knowledge of the damage resistance and damage tolerance properties of a laminated composite plate is useful for product development and material selection.

5.2 The residual strength data obtained using this test method is most commonly used in material specifications and research and development activities. The data are not intended for use in establishing design allowables, as the results are specific to the geometry and physical conditions tested and are generally not scalable to other configurations. Its usefulness in establishing quality assurance requirements is also limited, due to the inherent variability of induced damage, as well as the dependency of damage tolerance response upon the pre-existent damage state.

5.3 The properties obtained using this test method can provide guidance in regard to the anticipated damage tolerance capability of composite structures of similar material, thickness, stacking sequence, and so forth. However, it must be understood that the damage tolerance of a composite structure is highly dependent upon several factors including geometry, stiffness, support conditions, and so forth. Significant differences in the relationships between the existent damage state and the residual compressive strength can result due to differences in these parameters. For example, residual strength and stiffness properties obtained using this test method would more likely reflect the damage tolerance characteristics of an un-stiffened monolithic skin or web than that of a skin attached to substructure which resists out-of-plane deformation. Similarly, test specimen properties would be expected to be similar to those of a panel with equivalent length and width dimensions, in comparison to those of a panel significantly larger than the test specimen.

5.4 The reporting section requires items that tend to influence residual compressive strength to be reported; these include the following: material, methods of material fabrication, accuracy of lay-up orientation, laminate stacking sequence and overall thickness, specimen geometry, specimen preparation, specimen conditioning, environment of testing, void content, volume percent reinforcement, type, size and location of damage (including method of non-destructive inspection), specimen/fixture alignment and gripping, time at temperature, and speed of testing.

5.5 Properties that result from the residual strength assessment include the following: compressive residual strength F^CAI, compressive force as a function of crosshead displacement, and surface strains as functions of crosshead displacement.

Subcomité:

D30.05

Referida por:

D7956_D7956M-16R24, D8510_D8510M-23, D7136_D7136M-20, D4762-23, D6264_D6264M-23

Volúmen:

15.03

Número ICS:

83.120 (Reinforced plastics)

Palabras clave:

composite materials; compression after impact; compression testing; compressive residual strength; damage tolerance;