It is suggested that, where possible, extra stock be allowed to the overall width and length. Excess material can be then removed to hold final dimensions. Fabrication cracking, when noted, can include hot cracking, stress cracking and cracking related to heat treatment. Hot cracking is a condition generally confined to the fusion zone but occasionally can occur in the heat-affected zone. The creation of stress is inevitable during welding because of the complex thermal stresses that are created when metal solidifies.
Surface contaminates such as sulfur can contribute to hot cracking.
Certain geometric features such as concave weld deposits and tear-drop shaped weld pools can also lead to hot cracking. For each alloy system, a critical combination of these conditions can produce hot cracking. Hot cracking has also been found in C-276 alloy submerged arc welds when the amperage was above 400 amps. Cold cracking will occur in solidified weld metal and in base material only when externally applied stresses exceed the tensile strength of the alloy. Classical hydrogen embrittlement is not a fabrication cracking problem in nickel-based alloys.