## 5 Conclusions  
Using [PERSON]'s method, technological parameters and tool geometry were optimized for each material in the welded assembly. Also, considering the influence that each of the materials has on the other components of the welded assembly, the technological parameters used have changed as follows:  
* the holding force necessary to obtain parts with geometric parameters as close as possible to the nominal value was increased by an average of 52.9%, from an initial value of 45 kN to a final average value of 68.84 kN;
* the connection radius of the die was reduced, depending on each material in the welded assembly subjected to forming, as follows: for steel area 1, the connection radius of the die was decreased by 8.42%, from an initial value of 7 mm to 6.41 mm; for steel area 2, the connection radius of the die was decreased by 10.71%, from an initial value of 7 mm to 6.25 mm; for the weld line area, the connection radius of the die was decreased by 8.85%, from an initial value of 7 mm to 6.38 mm;
* the connection radius of the punch was reduced, depending on each material in the welded assembly subjected to forming, as follows: for steel area 1, the connection radius of the punch was reduced by 5.4%, from an initial value of 5 mm to 4.73 mm;  
Figure 13: Comparison between the estimated and experimental curves regarding: (**a**) maximum force, and (**b**) absorbed energy. \begin{table}
\begin{tabular}{l c c c c c c} \hline \hline
**Parameter** & **Fmax (kN)** & **Ea (J)** & **Fm (kN)** & **Ase (J/g)** & **Ef** & **Es** \\ \hline Estimated values & 17.726 & 1185.32 & 11.681 & 3.950 & 0.659 & 0.506 \\ Experimental values & 18.221 & 1177.26 & 11.702 & 3.923 & 0.642 & 0.503 \\ Difference \% & 2.97 & \(-\)0.68 & 0.18 & \(-\)0.68 & \(-\)2.54 & \(-\)0.71 \\ \hline \hline \end{tabular}
\end{table} 
Table 17: The values of the estimated general evaluation parameters and those obtained experimentally. for steel area 2, the connection radius of the punch was reduced by 9%, from an initial value of 5 mm to 4.55 mm; for the weld line area, the connection radius of the punch was reduced by 6.2%, from an initial value of 5 mm to 4.69 mm;  
Generally, it is noted that for this type of welded assembly, the holding force must increase, and the geometric parameters of the tools must have lower values than the nominal ones. By running the Genetic Algorithm, the final values of the obtained variables are characteristic of the 51 st generation of data of the space of potential solutions. The value of the objective function presents an error of 6.13% compared to the initial requirement  
The new TWB tubular structure has the following characteristics: the height of the area made of steel 1, which is the thicker steel sheet, is h\({}_{\text{S1}}\) = 82 mm, under conditions of a total height of 200 mm; absorbed energy E\({}_{\text{a}}\) = 1177.263 J, value very close to the nominal established value; strain rate efficiency E\({}_{\text{s}}\) = 0.503, a value that shows minimal differences from the theoretically set value. By adequately positioning the weld line, the deformation can be distributed over the entire TWB tubular structure, effectively controlling the height of the crashed area. The weld line has a decisive influence on the distribution of stresses and strains at the time of dynamic impact loading, ensuring a higher rigidity than the transition zone between the two materials, thus improving the overall behaviour of the structure. The data from using the Genetic Algorithms method regarding the dynamic impact process of TWB tubular structures are obtained experimentally. These results indicate the successful use of Genetic Algorithms in the qualitative and quantitative assessment of dynamically crashed thin-walled tubular structures made of tailored welded blanks. Conceptualization, V.A.C. and V.Z. ; methodology, V.A.C. ; software, V.A.C. and M.C.R. ; validation, V.A.C., V.Z. and M.C.R. ; formal analysis, V.A.C. and E.H.; investigation, V.A.C., E.H. and M.C.R. ; resources, V.A.C., V.Z. and E.N. ; data curation, V.A.C.