Reheat Cracking
Reheat cracking occurs when a weld or metal part is heated back into the critical temperature zone during a subsequent heat treatment. This leads to stress buildup and possible cracking.
Physical-Chemical Mechanism of Action
Reheat cracks form due to renewed stress buildup in the weld or metal part during a subsequent heat treatment. The material structure changes again, leading to stresses that can cause cracking.
Metallurgical Relevance & Welding Risks
A reheat crack can lead to hot cracks in the weld, which affect the material more severely than during the first heat treatment. This can result in component failure or reduced service life.
Workshop Practice & Action Items
Avoid re-heat treatment of the weld or metal part unless absolutely necessary. If heat treatment is required, make sure to avoid the critical temperature zone or stabilize the material structure before heat treatment.