__________________ is when the weld metal deposited is inadequate to bring the weld’s face or root surfaces to a level equal to that of the original plane.
a) defect
b) underfill
c) undercut
d) Porosity
The correct answer is b) underfill.
Underfill is a welding defect that occurs when the amount of weld metal deposited is insufficient to bring the weld's face or root surfaces to the same level as the original plane. This can result in an uneven or concave surface, leaving a gap or indentation between the weld and the base metal.
To find the answer to this question, one can start by understanding the different welding defects. By having knowledge of welding defects, you can eliminate options a) defect and d) porosity, since they refer to more general welding issues.
Next, you need to understand the specific meaning of each remaining option. Undercut refers to a groove on the toe of the weld or base metal caused by overheating, and it does not specifically address an inadequate level of weld metal. On the other hand, underfill directly relates to insufficient weld metal deposition. By understanding these definitions, you can confidently select option b) underfill as the correct answer.