Influencia del calor de entrada sobre el comportamiento a la fractura dúctil Charpy de la ZAC recalentada en uniones soldadas multipasos GMAW en acero HSLA utilizando análisis fractográfico digital

Abstract

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

Comportamiento macromecánico de uniones soldadas de superficie (AA5083) utilizando soldadura con gas inerte de tungsteno con recocido de homogeneización en una sola etapa

“…Although the overall reduction in mechanical properties is treated less critical for non-heat treatable in contrast to heat-treatable aluminum alloys (Kumar and Sundarrajan, 2009). Among various parameters of TIG welding heat input is the main process parameter that affects the mechanical properties of the welded joint (Vargas-Arista et al, 2019;Samiuddin et al, 2020). Results propose from tungsten inert gas (TIG) arc welding provides new ways of feasibility and for comparison purposes, which still seems to be a vacant space for this alloy from a research perspective.…”

Role of Bead Sequence in Underwater Welding

“…Several articles present the results of technological methods to improve the weldability of steel: diffusible hydrogen content in deposited metal [11,20], the use of austenitic deposits [9,21], preheating [22], and multilayer welding, including the temper bead welding technique [6,12,13,23]. Controlling the distribution of heat input by controlling the sequence and positioning of the beads is considered to be particularly promising, because it leads to a reduction in the grain size and provides decreased hardness and increased impact strength [24,25,26]. Different variants of bead sequences are used to weld hard-to-weld metals such as cast iron, nuclear steel, aluminum, quenched and tempered steel, and thermomechanically-treated steel [27,28,29,30,31,32,33,34,35].…”