Students have previously studied the weld process/technique-related flaws. Their presence does not
really depend on the type of steel being welded and, therefore, these are not discussed further in this
chapter. Other elements of good weldability (mechanical properties and the absence of metallurgical
flaws) do however, depend on the type of steel being welded.
Prevention of hydrogen cracking, one of the potential metallurgical flaws that can be present in the
weld zone, is one of the most important considerations in designing welding procedures. Besides the
steel type/composition, two other factors determine if hydrogen cracking can occur in the weld joint.
These factors are: the rate at which the weld cools once it has been heated by the welding arc; and,
the presence of locked-in stresses.