As with all aerospace materials, manufacturers must quality test their composites at every step of the process—from design to final product—to ensure that parts and components remain free of damage and compliant with a broad spectrum of industry standards. Composite testing also analyzes the composite’s structure to make sure that it has properly cured, as air bubbles or improper layering can cause cracks and catastrophic failures. Missing defects or design flaws in parts made from composites can severely damage your reputation and brand, not to mention potentially harm equipment, personnel, and passengers.
Here’s five more of the top composite testing methods for establishing materials characteristics:
Peel strength usually refers to the bond between a material and a coating or adhesive. Accurately measuring peel strength helps designers assess whether a material can withstand physical, chemical, or microbial damage. Specific to aerospace manufacturing, this test typically examines the adhesive properties of sealants used in manufacturing under various stresses.
Resin Penetration Testing
Aerospace manufacturers typically seal laminate layers of composite materials with resin, and then they cure it using a catalyst such as heat and/or pressure depending on the composite design. Resin penetration tests measure resin flow levels during the curing process at varying temperatures or pressures to compare different resins and determine the optimal curing conditions.
Pin Bearing Strength
This test relies on open- and close-hole tension/compression testing to determine the effectiveness and bearing strength of a pin or bolt should an unexpected hole form in the material. Static pin bearing strength tests apply stress risers to the specimen, helping designers and engineers to measure the point at which a material becomes unsafe.
This test applies a lateral shear force to the test sample until failure. To determine a material’s shear strength, the test must assess the maximum shear stress that a material can sustain before it fails. This test is commonly used to test adhesive efficacy.
Tensile Properties (̶̶−100°F to 660°F)
Engineers can determine the tensile properties of a material by applying stretching forces to the test sample and monitoring its effectiveness and behavior under these forces. A wide variety of materials used in spacecraft require tensile testing before they’re cleared for deployment, including paper, elastic materials, composites, and fabrics.
This list is not complete, there are several other materials testing methods for composites. If you'd like a more comprehensive guide, click here to download our eBook "Composites Testing for the Aerospace Industry".