Chevron cracking is a particular orientation of hydrogen cracking in carbon manganese weld metals. It is orientated approximately transverse to the weld direction and also close to 45° to the weld surface. Thus, on a longitudinal section, of a multipass weld, it may show as a 'chevron' marking owing to the fact that it is sometimes orientated at 'opposite' 45° in different weld runs. In practice, it has been found to occur more often in submerged arc (SAW) welds than in other processes but is not confined to that process.
As with any form of hydrogen cracking, its prevention follows the same basic factors. These are based on establishing 'safe' welding conditions and avoidance of the formation of hard, susceptible microstructures. Further information can be found in 'Fabrication cracking mechanisms in ferritic steels - a guide to best practice'
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