In the context of bonding, what is "primary bonding" characterized by?

Primary bonding is characterized by the process of laminating uncured plies together. This method involves laying down layers of composite materials that have not yet undergone a curing process, allowing for a strong, cohesive bond to form between the layers. During the curing process, chemical reactions lead to the hardening of the resin, which fuses the layers into a single, robust structure.

Using uncured plies facilitates proper alignment and integration of the layers before the curing stage, which is essential for achieving optimal strength and performance characteristics in composite materials.

In contrast, the other options pertain to different bonding or curing techniques that are not classified as primary bonding. For instance, using cured plies pertains to secondary bonding, where layers are joined after they have been fully cured. High-temperature curing focuses on the conditions of the curing process rather than the layering technique itself. Performing thermal welding involves joining materials through heat, which is a separate process from the laminating of uncured plies in primary bonding.