Check-cracking, or checking as it’s sometimes called, occurs in the metal carbide families and can be seen as cracks that are perpendicular to the bead length. They generally occur from 3/8 to 2 inches apart and are the result of high stresses induced by the contraction of weld metal as it cools.
The cracks propagate through the thickness of the weld bead and stop at the parent metal, as long as it’s not brittle. In cases in which the parent metal is hard or brittle, you should select a buffer layer of a softer, tougher weld metal. The austenitic family is a good choice for a buffer deposit.
