Most rivets used in the aviation industry are made of aluminium and aluminium alloys. Aircraft rivets can be identified by the shape of the head of the rivet. Though there are many types of head designs, the most common can be broken down into three categories: plain, dimpled and patterned.
Plain Head Rivets
Perhaps the most iconic rivet type, plain head rivets are domed in shape. The actual domed head varies from a shallow design to hemispherical in shape. Domed rivets are easier to manufacture than some other types of rivets with more intricate designs.
Dimpled rivets can be identified by the indentation in the head of the rivet. The head can range from slightly raised with a dimple to flat. Additionally, these rivets may have one dimple in the middle to a few dimples.
The biggest of the three general categories of aircraft rivets, patterned rivets come in an assortment of shapes and styles. Some have crosses indented in the rivet and look very much like common screws. Other rivets have raised dashes to identify them.