On shaft-hub hybrid couplings

Press-fitted and adhesively bonded joints (Hybrid Joints) are increasingly used as an alternative way to traditional structural joining techniques. The main achievable benefits can be summarized in the possibility of maximizing the load transfer (torque or axial) and reducing both the weight and the stress field of the components, by taking advantage of the adhesive strength. Hybrid joints studies can be found in technical literature mainly on steel-steel components (Steel Hybrid Joints). The aim of this paper is to provide some relevant information on the static and fatigue strength properties in the case of steel-aluminium components (Mixed Hybrid Joints), from the experimental tests performed on a high strength, single-component adhesive, which cures anaerobically. The use of the adhesive increases the press-fitted joint performances, with respect to its release force: the adhesive static shear strength is about 9MPa, whereas the adhesive endurance limit is about 6MPa, in presence of a stress ratio R=0.1.