A type of weld cracking that usually occurs below 203C (400F). Cracking may occur during or after cooling to room temperature, sometimes with a considerable time delay. Three factors combine to produce cold cracks: stress (for example, from thermal expansion and contraction). hydrogen (from hydrogen-containing welding consumables), and a susceptible micro.structure (plate martensite is most susceptible to cracking, ferritic and bainitic structures least susceptible). See also hot cracking, lamellar tearing and stress-relief cracking.