Lamellar tearing
Lamellar tearing is a step-like fracture parallel to the rolling plane, triggered by high shrinkage stresses in the thickness direction. It occurs preferentially in thick-walled components.
Physical-Chemical Mechanism of Action
Lamellar tearing occurs due to the arrangement of parallel layers in the metal that separate under high stress. This separation fracture follows a stepped pattern and is particularly dangerous in thick-walled components.
Metallurgical Relevance & Risks in Welding
Lamellar tearing can lead to severe cracks that run parallel to the rolling plane. This can damage the entire component and impair its load-bearing capacity. It occurs especially in metals with high carbon content when shrinkage stresses are too high.
Workshop Practice & Instructions
To avoid lamellar tearing, careful process planning is important. This includes:
• Optimal welding temperature and time to minimize shrinkage.
• Use of filler materials or stress-relief measures to control shrinkage stresses.
• Careful control of rolling direction and rolling process.