Contents lists available at ScienceDirect Composite Structures journal homepage: www.elsevier.com/locate/compstruct Numerical modelling of the mechanical behavior of hybrid joint obtained by spot welding and bonding Juliana P.B. Souza a, ⁎ , Ricardo A.A. Aguiar a , Hector R.M. Costa a , João M.L. Reis b , Pedro M.C.L. Pacheco a a Mechanical Engineering and Technology of Materials Graduate Program – PPEMM, Centro Federal de Educação Tecnológica Celso Suckow da Fonseca – CEFET/RJ, Av. Maracanã, 229, 5° andar, Rio de Janeiro, Brazil b Laboratory of Theoretical and Applied Mechanics – LMTA, Mechanical Engineering Graduate Program – PGMEC, Universidade Federal Fluminense – UFF, Rua Passo da Pátria, 156, Bloco E, sala 216, Niterói, Rio de Janeiro, Brazil ARTICLE INFO Keywords: Finite Element Analysis Numerical modelling Welding parameters Hybrid joints ABSTRACT Hybrid joints can be obtained using two or more techniques to attach two materials. This technique was well discussed, in the last two decades, for the use of different welding process. The development of new structural adhesives improved the use of adhesive bonding in the manufacturing sector to join assemblies, specialty aerospace and automotive industries. Compared to the common welding methods, adhesive bonding has many advantages such as simplified process, favorable fatigue properties, and the ability to join dissimilar metals. Weld bonding as a hybrid welding method combines welding and adhesive bonding to join metals. This work presents a numerical model based on the finite element method to assess the mechanical response of spot weld and hybrid joints composed by the combination of spot welding and bonding. The numerical model considers constitutive and geometric nonlinearities and is used to study the stress distribution and failure of the spot welding and weld bonding joints. A cohesive zone model is used to represent the adhesive bonding behavior. Numerical results are developed to assess the joints capability of the supporting loading and the stiffness joints. Experimental data obtained from previous works is used to calibrate the numerical model. 1. Introduction Fricke et al. [1] reported that to manufacture multi-material hybrid parts for the automotive industry, mechanical joining processes like riveting are well established. However, adhesive bonding is increas- ingly being used in the car body to realize lightweight structures with high crash performance using a multi-material design. They also con- cluded that the synergetic combination of the specific advantages of both joining techniques in form of hybrid joints results in joint im- provements of manufacturing, crash, and durability performance. Hybrid joints obtained by a combination of two simple techniques, e.g. by spot welding and adhesive, are relatively modern joints devel- oped especially for application in aerospace industry [2]. This con- tribution describes the modelling and testing of structural elements by application of an angle bar and spot welding techniques with the in- troduction of adhesive layers between adherends. Numerical modelling of the mechanical response using the Finite Element Analysis requires a description of 3 different damage processes: (1) plastic degradation of the spot welded points, (2) plastic deterioration of the joined parts around the regions of spot points and (3) degradation of the adhesive layer. According Golewski et al. [3], the variable thickness creates chamfer defined by a geometric parameter which has a very positive influence on the mechanical response of the joint. The most difficult task in the numerical modelling of the joint de- formation process is the description of progressive damage behavior of joined parts and the adhesive. Up to now most papers deal with a modelling of single lap hybrid joints without consideration of the da- mage processes which develop in many parts of the joint subjected to mechanical loading. And the results revealed premature adhesive layer debonding, while the maximum load was governed by the spot weld [4]. Bartczak el al [5] used a hybrid joint of car body and concluded that https://doi.org/10.1016/j.compstruct.2018.01.066 Received 15 January 2018; Accepted 19 January 2018 ⁎ Corresponding author. E-mail addresses: juliana.souza@cefet-rj.br (J.P.B. Souza), ricardo.aguiar@cefet-rj.br (R.A.A. Aguiar), hector.costa@cefet-rj.br (H.R.M. Costa), jreis@id.uff.br (J.M.L. Reis), pedro.pacheco@cefet-rj.br (P.M.C.L. Pacheco). Composite Structures xxx (xxxx) xxx–xxx 0263-8223/ © 2018 Elsevier Ltd. All rights reserved. Please cite this article as: Juliana, P.B., Composite Structures (2018), https://doi.org/10.1016/j.compstruct.2018.01.066