Abstract: Numerical simulations of resistance spot welding with different electrode (?6mm, ?8mm cone electrodes, and ?16mm ball electrode) were performed by ANSYS to examine the effect of the nugget shape on the weld properties and the service life of the electrodes under the same parameters. Continuous spot welding is carried to verify the correctness of the finite model. The results indicate that as for the cone electrode, the smaller the diameter of the electrode is, the larger the size of the nugget, and the weld joint has good performance. The contact area between the ball electrode and the work piece is too small and the joule heat generated is large. So, the ignition loss of electrodes is a crucial problem for the ball electrode. The simulation results are in good agreement with the metallographic results. The service life is improved by 20% compared with the ball electrode when the 5052 thin plate is welded by ?6mm cone electrode, which provides the theoretical basis for selecting the electrode shape.

Key words: 5052 aluminum alloy; resistance spot welding; electrode burned; finite element simulation