Investigation of Electron Beam Welding of AHSS by Physical and Numerical Simulation

The electron beam welding (EBW) sets new standards as it facilitates very high quality and effective welding of high strength structural steels. The technology ensures high-quality critical welded joints in thicker structural metals. It has a high energy density in comparison to the conventional arc welding processes (e.g. GMAW). As a result of less overall energy input and higher velocity, the effect of welding on the base material in the heat-affected zone (HAZ) and the distortion is much smaller compared to conventional arc welding processes. The low heat input result in a small HAZ and a reduced extension of critical HAZ areas which can be favourable in high strength steels when the mechanical properties can drastically decrease in the HAZ. In comparison with experimental studies, a numerical modelling study can provide detailed information concerning the welding process and parameters, and the number of costly experiments can be reduced. Finite element modelling (FEM) of EBW enables the estimation of temperature field, time temperature curve, weld pool geometry and welding distortion etc. The determination of the temperature field can be very useful in terms of the further investigations since the t8/5 cooling time can be less than 2 s during EBW. In this paper, by the application of Sysweld software, the time-temperature curve was determined and the physical simulation of the critical HAZ subzones were performed using a GLEEBLE 3500 physical simulator in order to analyse the properties of HAZ during extremely short cooling time.