Welding constitutes a type of permanent joint in the assembly process in the secondary manufacturing industry such as construction for the manufacture of automobiles, aircraft, bridges, tanks, ships, pipes, among others. The objective of this research was to compare the mechanical tensile strength and hardness of welded specimens. The mechanical traction was to evaluate the resistance to breakage of the weld seams by the MIG/MAG process versus the SMAW welding process, on ASTM 36 base material. The hardness was to determine the plastic deformation of the area affected by heat during the fusion process. For this purpose, the universal testing machine was used to determine the stress-strain relationship of each process; while a hardness tester was used for hardness. In this experiment, 12 welded specimens and two non-welded control specimens were used to determine the quantitative deviatio...