The effects of hole diameter and squeeze force on the residual stress and shear properties of single riveted lap joint
Riveting is an important connection method for aircraft structural assembly,and most structural failures occur at the connection holes.Therefore,it is very important to comprehensively evaluate the quality of riveted joints.Taking single riveted lap joints as the research object,and through finite element simulation analysis and tensile shear experiments,the residual stress dis-tribution and shear properties around the holes of riveted joints were studed under different combinations of squeeze force and hole diameter riveting process parameters.The finite element analysis results show that increasing the squeeze force can significantly expand the longitudinal residual compressive stress distribution area around the hole,and make the maximum longitudinal residual tensile stress occur far from the edge of the hole,while the influence of the hole diameter on the longitudinal residual compressive stress distribution area was only significant;the tensile shear test shows that the failure mode of the single riveted lap joint struc-ture was the instantaneous fracture of the rivet along the shear surface.The shear properties of the riveted joint formed with a 21 kN squeeze force at a hole diameter of 4.20 mm was the best,with an average peak load of 4.09 kN,which is about 9.36%higher than that of the riveted joint formed with a combination of hole diameter of 4.04 mm and 15 kN squeeze force parameters.Increasing the hole diameter can improve the shear properties of single riveted lap joints,but it will reduce the longi-tudinal residual compressive stress distribution area around the hole,which will have an adverse impact on the fatigue life of rive-ted joints.Increasing the squeeze force appropriately can not only expand the distribution area of residual compressive stress but also improve the shear properties of the joint.
single riveted lap jointhole diametersqueeze forceresidual stressshear properties