Answer :
Final answer:
Weld reinforcement refers to the excess weld metal beyond what is necessary to fill a weld groove, which can compensate for metal shrinkage during cooling.
Explanation:
Weld reinforcement is best described as weld metal in excess of the quantity required to fill the weld groove. It is often seen as the extra metal on the face or root of the weld, beyond what would be necessary to fill a joint to meet its specifications.
This excess material can help to compensate for shrinkage as the metal cools, but too much reinforcement can lead to inefficiency in the use of welding material and can affect the performance of the weld under certain conditions.