## 3 Results and Discussion
Figure 7: Weld interface SEM image (from area D in Figure 2). vi and vi are the areas where EDS performed. Moreover, all materials in the HEAs powder on the Al and Fe sides (indicated as v-vi in Figures 6 and 7) were similar to the HEAs powder used as the filler. The elements Al and Fe were not identified in these areas, showing that using HEAs as a filler prevents the interaction of Al and Fe. The small dark dots in Figures 6 and 7 are vanadium particles (indicated by vii in Figure 7). A small amount of non-melted material particles were identified in the weld interface, which did not influence the joint strength [57]. Figure 8 shows the weld's tensile shear fracture, along with the HEAs/Al interface; this area was the weakest in this joining [58]. The influence of heat and the weak IMC formed between HEAs and Al in this region led to this failure. In Figure 9, all the tensile fractures occurred around the weld interface between the HEAS/Al alloy, and dimples could be seen on the fracture surface, indicating a ductile fracture mechanism for the specimen. When comparing the tensile characteristics of non-filler laser lap welding to the HEAs powder filler induced laser-beam welding, filler-less laser lap welding had a lower tensile shear strength [59; 60]. In addition, the on-filler laser lap weld joint's ductility was higher than the HEAs filler-induced laser welding. The latter finding, and the investigation results, suggest that the production of coarse columnar grains in the weld joint reduces ductility. \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline \multirow{2}{*}{**Area**} & \multicolumn{8}{c}{**Composition in Weight\%**} & \multicolumn{2}{c}{**Related**} \\ \cline{2-9}  & **Co** & **Cu** & **Ni** & **Al** & **Fe** & **V** & **Mn** & **Phases** \\ \hline A (i) & 0.98 & 6.21 & 3.04 & 68.98 & 0.00 & 20.02 & 1.95 & Al\({}_{3}\)V \\ \hline B (ii) & 12.98 & 19.72 & 14.87 & 0.00 & 0.00 & 29.01 & 18.71 & DCC + V (SS) \\ \hline C (iii) & 11.26 & 11.98 & 17.47 & 0.00 & 12.21 & 29.24 & 19.29 & DCC + V (SS) \\ \hline E (v) & 16.02 & 20.01 & 15.82 & 0.00 & 0.00 & 28.49 & 19.82 & DCC + V (SS) \\ \hline G (vii) & - & - & - & - & - & 98.63 & - & V \\ \hline \hline \end{tabular}
\end{table} 
Table 3: EDS results with respect to different areas in the weld zone. Figure 8: Cross-section of weld fracture. The fracture locations of the tensile-tested parent metal and welds showed that the failure modes were ductile with adequate plastic deformation. Figure 9 shows a significant difference in the size and placement of the dimples on the fracture surface of the joint. The existence of voids and the size variation of the dimples indicated that the ductile fracture occurred with a significant drop in the tensile strength of the laser weld joint [61; 62; 63]. Several micro-pores were also identified, which might have been the reason for the lower tensile strength compared to the parent metals. Figure 9 shows a coarse and extended dimple fracture that could break under ductile shear. The elongated cavities and coarse dimples indicated localized slip, resulting in increased ductility, without lowering the tensile strength of the HEA-induced laser joint. Figure 10 reveals a minor brittle cleavage fracture in the tensile-tested fractography. However, there was a noticeable variation in fracture patterns. The predominant properties of the HEAs filler and fine secondary dimples enhanced the tensile strength of the HEAs-filler-induced laser joint. The fractography (Figures 8-10) illustrates the specimen's ductile and brittle fracture properties [64]. The presence of the  
Figure 10: Cleavage surface. Figure 9: Fracture surface with dimples. Al\({}_{3}\)V phase was verified using XRD data from the fracture cross-section, as shown in Figure 11.  
Figure 12 shows the tensile stress-strain curve at room temperature for the HEAs-powder-filler-induced laser welding. The tensile fracture was prolonged at the weldment's HEAs/Al metal interface. The weld had a tensile strength of 237 MPa.