Both the rivet and the materials to be fastened will affect the ultimate joint strength. The rivet body material selection would generally be the same as the material(s) being assembled, i.e. an aluminium body into an aluminium section. A marked dissimilarity of materials may cause joint failure due either to material fatigue or galvanic corrosion. Stainless steel rivets offer best anti-corrosion performance.
The low-profile dome head rivet is appropriate for most applications. However, when soft or brittle materials are fastened to a rigid backing member, the large flange head rivet should be considered, to spread the load over a greater surface area. Where a flush surface is required, the countersunk head rivet style should be selected.
Hole size can be important in blind riveting. Too small a hole will, of course, make rivet insertion difficult and conversely too big a hole will cause a rivet to fail. Best practice is to accurately follow the hole size recommendations provided in the technical data.
Joint Thickness (Grip Range)
Firstly, measure the total thickness of the materials to be joined. This will determine the required “grip” of the rivet. Refer to the “Grip Range” column in the technical data, and select a rivet with a grip range that includes the thickness required. Please note that insufficient rivet length will not allow the proper formation of the secondary head at the back of the work and could result in rivet failure.
Rivet Joint Strength
The single-joint tensile and shear values vary from application to application. The functions of total joint strength, fastener spacing, rivet body material and rivet diameter are all factors that result in the final shear and tensile strengths required. Structural rivets offer the ultimate in shear and tensile strengths. Refer to the technical data supplied for typical strength values.