**5. Conclusions**

This work presents a numerical method for predicting the thickness of the intermetallic (IM) layer formed at the bonding interface in dissimilar welding of aluminum alloy EN AW-6014 T4 sheets to galvanized steel DC04 sheets. The method allows fast estimation of the layer thickness and visualization of the layer growth, because the highly irregular microscopic interface between the IM layer and the weld seam is approximated as a smooth surface. Based on the numerical results, which were also validated with single-sided cold metal transfer (CMT) welding experiments, the following conclusions can be drawn:


**Author Contributions:** Z.S. did the administration and conceptualization, developed the experimental and numerical methodologies, performed the literature review and the numerical simulations, evaluated the experimental data, validated the experimental and the numerical results, as well as prepared and edited the manuscript. W.K. was responsible for performing the welding experiments, M.H. for producing the filler alloy. B.G. and C.S. reviewed the manuscript and supervised the work.

**Funding:** The authors would like to thank the Austrian Research Promotion Agency (FFG) for the financial support of this study. Open access funding is provided by the Graz University of Technology.

**Acknowledgments:** Thanks go to Helmut Treven for assisting the welding experiments as well as to Lukas Potgorschek for doing the metallographic preparations and for operating the optical geometry scanning system.

**Conflicts of Interest:** The authors declare no conflict of interest.
