Finite Element Simulation of Ductile Failure Process of Spot Welded Joint under Tensile Loading

Abstract:

Deformation response and failure process of a spot welded joint are investigated in this study. For this purpose, a cross-tension spot welded joint sample made of dual phase steel sheets (DP600) is prepared and tensile tested to failure. Complementary FE simulation of the test is performed. The FE model acknowledges the variation of properties across the spot welded region. Rice-Tracey ductile damage model is approximated and employed in the simulation. Close comparison of load-displacement curves and deformed shape with measured values serve as validation of the FE model. Results show that FE simulation with damage-based model adequately predicts tensile deformation and failure of the spot welded joint. Tensile failure of the joint is confined to the heat affected zone and heat affected/fusion zone interface of the joint. Localized through-thickness necking of the sheet metal is captured. In addition, the predicted fracture of the spot welded joint is accompanied by localized extensive plastic deformation.

• Periodical: Applied Mechanics and Materials (Volume 660)
• Pages: 623-627
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.660.623
• Online since: October 2014
• Authors: Mohamad Shahrul Effendy Kosnan, Zaini Ahmad, Abdoulhdi Amhmad Borhana, Mohd Nasir Tamin*
• Keywords: Ductile Damage, Equivalent Plastic Strain, Finite Element Simulation, Spot Welded Joint

References

[1] C.S. Orosz, B. Palotás, J. Dobránszky, Welding investigations of modern high strength dual phase and TRIP-steel for automotive industry application, Materials Science Forum. 537 (2007) 431-438.

DOI: 10.4028/www.scientific.net/msf.537-538.431

[2] S. Dancette, D. Fabregue, R. Estevez, V. Massardier, T. Dupuy, M. Bouzekri, A finite element model for the prediction of advanced high strength steel spot welds fracture, Engineering Fracture Mechanics. 87 (2012) 48-61.

DOI: 10.1016/j.engfracmech.2012.03.004

[3] W. Noh, D.H. Yoo, Y.W. Koh, K.S. Chung, X. Yang, Failure evaluation of spot welds for advanced high strength steel sheets, Key Engineering Materials. 504 (2012) 131-136.

DOI: 10.4028/www.scientific.net/kem.504-506.131

[4] G.R. Johnson, W.H. Cook, Fracture characteristics of three metals subjected to various strains, strain rates, temperatures and pressures, Engineering Fracture Mechanics. 21(1) (1985) 31-48.

DOI: 10.1016/0013-7944(85)90052-9

[5] A.R. Rusinek, R. Zaera, J.R. Klepaczko, Constitutive relations in 3-D for a wide range of strain rates and temperatures–application to mild steels, Int. J. Solids Structures. 44 (2007) 5611.

DOI: 10.1016/j.ijsolstr.2007.01.015

[6] H.N. Han, K-H. Kim, A ductile fracture criterion in sheet metal forming process, J. Materials Processing Technology. 142(1) (2003) 231-238.

DOI: 10.1016/s0924-0136(03)00587-9

[7] J. Hancock, A. Mackenzie, On the mechanisms of ductile failure in high-strength steels subjected to multi-axial stress-states, J. Mechanics and Physics of Solids. 24(2) (1976) 147-160.

DOI: 10.1016/0022-5096(76)90024-7

[8] A.A. Borhana, A.T. Mohamad, A. Abdul-Latif, Z. Ahmad, A. Ayob, M.N. Tamin, Ductile failure prediction of spot welded lap joint, App. Mechanics and Materials 165 (2012) 285-289.

DOI: 10.4028/www.scientific.net/amm.165.285

[9] D8. 1M: 2007, A specification for automotive weld quality - resistance spot welding of steel. (2007).

[10] J.R. Rice, D.M. Tracey, On the ductile enlargement of voids in triaxial stress fields, J. Mechanics and Physics of Solids. 17(3) (1969) 201-217.

DOI: 10.1016/0022-5096(69)90033-7

[11] D.M. Tracey, Strain-hardening and interaction effects on the growth of voids in ductile fracture, Engineering Fracture Mechanics. 3(3) (1971) 301-315.

DOI: 10.1016/0013-7944(71)90040-3