What is the primary purpose of a rivet in metal structures?

The primary purpose of a rivet in metal structures is to join adjacent materials. Rivets are mechanical fasteners that create a permanent bond between two or more components, typically metal sheets or structural elements. When installed, a rivet is deformed (or 'upset') on one end, securing the materials together tightly, which is crucial in ensuring the structural integrity and strength of aircraft and other metal constructions.

While rivets may contribute indirectly to the tensile strength of a joint when they are properly installed, their fundamental role is to act as a fastener that connects parts. Other options, such as providing decorative features or preventing corrosion, do not align with the primary structural function of a rivet. The main focus of a rivet is its ability to hold components together securely under various loads, crucial for maintaining the safety and performance of metal structures, especially in aerospace applications.