Solid / Snap Head Rivets 

Solid rivets are among the simplest, most reliable, and oldest types of fasteners. It is a two-piece rivet that can be used to join two or more materials of different thicknesses. These round-headed rivets were commonly used in large structural work where strength is needed. Snap head rivets are widely used in various industries like manufacturing and construction. Snap head rivets have applications where you need a permanent joint.
Also, these rivets are used in traditional boiler-making, shipbuilding, and bridge girder construction, for example, large iron Snap Head Rivets were passed through the plates to be joined and hammered over whilst red hot. This not only made the hammering over easier but, as the iron rivet cooled, the joint tightened due to its contraction.