Remote laser welding of Zn coated IF steel and 1050 aluminium alloy: processing, microstructure and mechanical properties

The integrity of steel-aluminium dissimilar alloy joints is dependent on the intermetallic phases (IMCs) and extent bonding area. excessive growth brittle AlxFex IMCs within weld pool interfaces disadvantageous due to initiation propagation hot cold cracking during solidification. purpose this work was assess development Remote Laser Welded (RLW) Zn coated interstitial free (IF) steel 1050 aluminium alloy, which can be used in cooling circuits electrical connectors automotive applications. Welding experiments with variable RLW parameters (power, welding speed focal offset) were performed study formation impact joint integrity. Results showed that while conduction mode (at power densities 0.13–0.18 MW/cm2) three identified through SEM/EDX EBSD: η – Al5Fe2, κ AlFe3 θ Al13Fe4 possessed nano-hardness indentation values approximately 12, 5 GPa, respectively; they formed a non-continuous interfacial layer, composition remained homogenous, minimal. On contrary, keyhole 0.16–0.40 welded samples produced continuous thick IMC and/or an inhomogeneous mixing aluminium, up 10 wt.% Al pool. nominal lap shear strength for sample 77%, respect weakest material (Al). This found close link between chemistry significantly determined distribution thickness, mechanical properties.