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Corrosion has been frequently recognized as failure's root cause for diverse engineering components like those associated to production lines, like in boiling water reactor piping systems (1). It is important that several electrochemical techniques help conjointly to elucidate some of the corrosion specificities, like localized corrosion of traditional materials. Pitting corrosion has been usually reported to affect stainless steels because it engages more frequent than not, second phase particles that precipitate out at the matrix and the grain boundary network, thereby consuming alloying elements that, for example, participate on sustaining passivity. Thermally-dependent fabrication operations such as welding bring about sensitization, particularly within the 450 to 700 ºC range. Exposure propitiates nucleation and growth of chromium carbide networks: this makes the boundaries and neighboring areas sensitive to depletion. Thus the precipitates are directly suspect of significant decrements in protective potential as the chromium has been chemically bound to carbon, thereby decreasing the surface passivating abilities. Therefore, the present work reports the electrochemical and microscopy results obtained after immersing the heat treated SS304 samples for diverse periods in a suitable electrolyte to studying their potentiodynamic polarization and EIS behaviors.

The copper electrodeposition process was studied onto different gold substrates, single crystal (111) and polycrystalline, using chronoamperometry. The potentiostatic current transients were analysed; it was found that, in both cases, different electrodeposition processes take place. In the underpotential region, the transients involve three types of processes, one of adsorption and two nucleation ones limited by the incorporation of ad-atoms, thus giving bidimensional growth for both electrodes.

The effect of the heat input on the fracture behavior of reheated heat affected zone in multilayered welded joints of ASTM A633 steel was evaluated using the impact test, fractography, scanning electron microscopy and digital images processing. The impact results indicated a reduction in the Charpy energy as a function of the wire feed rate, which was confirmed by fractographs after digital images processing that showed a decrease in volumetric fractions of micro-dimples in ductile failures accompanying the increase in feed rate, favoring brittle fractures in transgranular cleavage facets containing river marks. The minimum fractions in micro-voids and the largest size of facets showing a higher number of river patterns were found at maximum feed rate of 200 mm·s -1 . Heterogeneous microstructure of heat affected zone formed by fine acicular ferrite network surrounded by allotriomorphic ferrite showed that an increase in the feed rate induced a grain refinement by the formation of acicular ferrite, which was linked to the deterioration of absorbed energy and brittle failures. Citation/Citar como: Vargas-Arista, B.; Mendoza-Camargo, O.; Zaragoza-Rivera, I.P.; Medina-Flores, A.; Cuevas-Salgado, E.; Garfias-García, F.; García-Vázquez, F. (2019). "Influence of heat input on the Charpy ductile fracture behavior of reheated HAZ in GMAW multilayer welded joints on HSLA steel using digital fractographic analysis". Rev. Metal. 55(2): e143. https://doi.org/10.3989/revmetalm.143

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