Composite Materials Testing

Early in the design, composite materials properties can be drawn from a reputable database or manufacturer’s datasheets. However, as the design develops the materials should be tested in conditions close to the manufacturing process that is going to be employed in the final component.

Material properties include: Young’s Modulus, Poissons Ratio, compressive, tensile, flexural and shear strengths, interlaminar shear, in-plane shear response, mixed mode interlaminar facture toughness, fastener pull-through, fatigue, fracture toughness, strain energy release rate, damping. As an added complication, many of the material properties are direction-dependent (i.e. orthotropic). Whereas metal or plastic exhibit isotropic material behaviour (i.e. properties are the same in any direction), consequently, testing of fibre-reinforced composite materials must be performed in two different in-plane directions for a composite lamina.

Obtaining standard stiffness, strength or mechanical properties of composite materials can be challenging for designers. Engenuity are leaders in the field of test and analysis capability for a vast range of composite materials since the early 1990s, with in-depth knowledge of these material properties and implications for the complexities of design.

Engenuity’s testing activities consider initial material screening through to high confidence A and B basis allowable definition for aerospace composites. The test programme needs to be closely tailored to satisfy the end usage requirements for the results.