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This work discusses several aspects of the weldability of AA5083-H116 butt-welded joints, using ER5183 filler material, automated GMAW-P process, and 80Ar19He1O2 shielding gas. The used methodology included the characterization of base metal, the development of welded joints using two different heat inputs, the microhardness profiles analysis on the cross section of the welded joint, and the microstructural evolution using microscopy. The above-mentioned measurements were complemented with residual stress evaluation using the x-ray diffraction technique, together with analysis of transversal and longitudinal tensile tests of the welded joints. The obtained results in welded joints indicated that yield strength, ultimate tensile strength, and ductility behavior have been influenced by heat input compared to base metal and reported values for similar alloys. Residual stress results showed that both the weld metal and adjacent coarse grain zone were subjected to tensile stresses, while the refined grain zone (FGZ) and base metal adjacent to the FGZ were subjected to compressive stresses. Additionally, the magnitude of residual stresses was smaller than maximum tensile stresses, and its behavior was related to both heat input and mechanical properties along welding regions. 

Controlling matter at the level of electrons using ultrafast laser sources represents an important challenge for science and technology. Recently, we introduced a general laser control scheme (the Stark control of electrons at interfaces or SCELI) based on the Stark effect that uses the subcycle structure of light to manipulate electron dynamics at semiconductor interfaces [A. Garzón-Ramírez and I. Franco, Phys. Rev. B 98, 121305 (2018)]. Here, we demonstrate that SCELI is also of general applicability in molecule–semiconductor interfaces. We do so by following the quantum dynamics induced by non-resonant few-cycle laser pulses of intermediate intensity (non-perturbative but non-ionizing) across model molecule–semiconductor interfaces of varying level alignments. We show that SCELI induces interfacial charge transfer regardless of the energy level alignment of the interface and even in situations where charge exchange is forbidden via resonant photoexcitation. We further show that the SCELI rate of charge transfer is faster than those offered by resonant photoexcitation routes as it is controlled by the subcycle structure of light. The results underscore the general applicability of SCELI to manipulate electron dynamics at interfaces on ultrafast timescales.