What type of discontinuity is commonly found in rolled plate?

• A. Laminations
• B. Shrinkage
• C. Lack of fusion
• D. Undercut

Answer: (A)

Laminations are a type of discontinuity commonly found in rolled plate due to the manufacturing processes involved in the rolling of metal. During the rolling process, if the metal is not properly heated or if impurities are present, it can lead to the formation of thin layers or "laminations" within the material. These laminations can significantly affect the structural integrity and mechanical properties of the metal, leading to issues during welding or machining.

Understanding the characteristics of laminations is essential for quality control in materials used in construction and manufacturing. They can act as stress concentrators and may lead to premature failure under load. Thus, identifying and addressing these discontinuities during inspections is crucial to ensuring the reliability and safety of the final product.