Carbon Fiber - 0200 Damage & Defects Porosity

Understanding Porosity in Carbon Fiber Composites

Porosity in carbon fiber composites refers to the presence of numerous micro-voids, typically smaller than a millimeter. Individually, these voids may not significantly impact structural integrity, but collectively, they can weaken the material’s mechanical properties to an unacceptable degree.

Porosity often arises from trapped air, moisture, or volatiles that become enclosed along fibers and between plies during the curing process, particularly when the resin transitions to its gel stage. These voids act as stress concentrators, compromising key mechanical properties such as flexural, shear, and compression strengths.

In composite manufacturing, porosity levels below 1–2% are considered negligible. For many components, 2% is the standard threshold for acceptable porosity, ensuring the material maintains its strength and performance.

Proper manufacturing techniques, quality control, and optimized curing processes are essential to minimize porosity and ensure the durability of carbon fiber components.