Fracture resistance of simulated heat affected zone areas in HSLA structural steel

Abstract

The fracture toughness of some areas in the multi-pass heat affected zone (HAZ) of a high strength low alloy (HSLA) structural steel was analysed in a straightforward way using precracked, cylindrical specimens tested on a conventional tensile machine. The specimens were made from samples with a simulated HAZ microstructure; however, the size of the samples was restricted by the limitations of the Gleeble machine. The brittleness of the samples was an indication of the detrimental effect of welding on their toughness. The specimens were not large enough for a direct K Ic measurement over a wide testing temperature range; it was necessary to modify the results. The low fracture toughness and the substantial shift of fracture transition temperatures suggest that welding of the investigated steel could be a delicate procedure. STWJ/430

Enseñar a cómo determinar el impacto de Charpy de acuerdo con los requisitos generales definidos en la parte UG del código ASME VIII división 1

“…Some of them, like inclusions, are intrinsic while others happening at different microstructural scales relate to processing conditions (Gutiérrez, 2014). Figure 4 (Gliha et al, 2004) shows schematically the changes of microstructure that occur in a multiple-pass weld. The zone affected by heat, whose microstructure is thickened by the first cycle, changes to different microstructures according to the thermal sequence of the subsequent passes.…”

Fatigue and brittle fracture of carbon steel of gas and oil pipelines

“…In a case of the welding joint, the deformation process which take place during the first stage are more dangerous since it is not uniformed and is under the assumption which represents by its composition 'welding seam Á zone of the thermal influence' (WSÁZthI) and necessarily contains the inhomogeneities of the structure as different admixtures and defects (Gliha et al 2004(Gliha et al , 2009(Gliha et al , 2011. This causes the concentration of tensions in the zone of the welding joint and additional risks of the breakage or failure takes place in the stages of the building or exploitation.…”

Role of tandem submerged arc welding thermal cycles on properties of the heat affected zone in X80 microalloyed pipe line steel

“…Curiel-Reyna et al (2006) have recently shown the strength and toughness of the HSLA microalloyed steels can be damaged by the thermal cycles during welding, causing fragility in the HAZ. Gliha et al (2004) have reported for single pass welding, the lowest toughness is expected in the coarse grained heat affected zone (CGHAZ), which is part of the HAZ near the fusion line. Moeinifar et al (2010) have recently reported welding processes with high heat input, such as tandem submerged arc welding (TSAW), cause larger prior-austenite grain sizes in the CGHAZ.…”