Research On Technology And Performance Of AA5052/DC52D Electromagnetic Self-piercing Rivet-bonded Joint

Electromagnetic self-piercing rivet(SPR)-bonding is a new joining technology combining of SPR joining and bonding joining.It is suitable for the joining of dissimilar materials and the mechanical performance of the joint is great.In addition,SPR-bonded joint has good tightness,waterproof and corrosion resistance,and has good safety and reliability.It has a broad application prospect in the field of automobile,aerospace and navigation.In this paper,the steel/aluminum alloy structure finite element simulation of the SPR process of SPR-bonded joint was carried out by ABAQUS.The shear mechanical properties and corrosion resistance of the joints were studied by comparing the SPR joints and bonded joints,and the failure and corrosion mechanism of the joints were analyzed.Firstly,the finite element model of the process of the SPR-bonded joint was established.At the same time,the stress evolution of the joint profile was analyzed,and it was found that the SPR-bonded joint was closely formed,which formed a good interlock structure,and cause little structural damage to the plate and the adhesive layer.In addition,the stress of the rubber layer in the process of riveting was analyzed,and it was found that the stress concentration was formed in the center of the lap area,which would make the adhesive layer and the sheets adhere more closely.Secondly,the shear mechanical properties of the SPR-bonded joints were studied by comparing with the SPR joints and the bonded joints.It was found that the shear strength of the SPR-bonded joint was close to that of the bonded joint,and the shear peak load reached18.3 kN.It was 177.3% higher than that of the SPR joints.Moreover,the failure absorption energy of the SPR-bonded joint was much higher than that of the SPR joints and the bonded joints,and even 11.9% higher than the sum of the two.It indicated that the SPR joining and the bonded joining played a coupling role in the shear failure process of the SPR-bonded joint.At the same time,it was found that the shear failure process of the SPR-bonded joint could be divided into two parts: adhesive layer failure and riveting failure.The adhesive layer failure mode of the SPR-bonded joint was different from that of the bonded joint.Finally,the corrosion behavior and corrosion resistance of three kinds of joints in neutral salt spray corrosion environment were studied.It was found that the salt solution could erode the sheets and produced corrosion products in the lap area for SPR-bonded joints.It permeated the adhesion area between the adhesive layer and the sheets in the SPR-bonded joints,which changed the failure mode of the adhesive layer.The process of riveting could make the adhesive and the plate closely together to improve the corrosion resistance of the SPR-bonded joint.On the one hand,the adhesive protected the joint lap area from corrosion.On the other hand,it protected the riveting structure from damage.