AWS Welding Inspection and Testing Certification Practice Test

Which discontinuity is most likely to be caused during the manufacturing of steel plate?

1. Porosity

2. Lamination

3. Undercut

4. Underfill

The correct answer is: Lamination

Lamination is a discontinuity that is most commonly associated with the manufacturing process of steel plates, particularly during the rolling or refining stages. It occurs when the layers or sheets of steel do not bond properly, leading to internal seams or cracks within the material. This can be a result of various factors, such as inadequate heating, insufficient rolling, or impurities in the steel during production. The presence of lamination can significantly affect the mechanical properties of steel and its suitability for certain applications, making it an important consideration in the quality control of steel manufacturing. The likelihood of lamination increases in thicker plates or during processes such as hot rolling, where the material is subjected to high pressure and temperature. In contrast, porosity typically arises from gas entrapment during welding or casting processes, while undercut and underfill are more related to welding defects. Undercut occurs when the weld metal does not completely fill the joint, and underfill involves insufficient weld material in the groove of the welded joint. These are less likely to occur during the manufacturing of steel plates compared to lamination, making it the most relevant choice in this context.