Effects of single-lap joint at different adhesive thicknesses on fatigue strength of metals with different surface coatings

Adhesive technology defined as a kind of chemical bonding alternative to thermal and mechanical joints, has attracted the attention of industry people and researchers in various fields, especially in the automobile sector for the last 30 years. Therefore, this research study has aimed to consider the issue in the automotive industry, the adhesion performance was investigated for the cases in which a metal part was joined to a vehicle body both after applying coatings and primer paint respectively. In this respect, some of the test samples were prepared by being coated with cataphoresis, while some others were produced with primer painting along with the ones that do not have any coating or painting on them. Following this procedure, single lap type joints with different adhesive thicknesses were manufactured and subjected to fatigue tests. To make a comparison of their fatigue endurances, spot welded joints, as an alternative bonding method, were also subjected to the fatigue test. It was clearly observed that the spot welding joints have surpassed their adhesive counterparts in fatigue performance, and the samples coated with cataphoresis have outperformed among the adhesion type bonds.