Question

which of the following best describes the heat - affected zone (haz) in welding?
a it is the zone where the metal has melted completely.
b it is the area next to the weld where the metals structure changes due to heat.
c it marks the area where new metal is added to the weld.
d it shows where the base metal is unchanged.

Explanation:

The heat - affected zone (HAZ) in welding is the area adjacent to the weld where the base metal's microstructure changes due to the heat input during welding, but it does not melt completely. New metal addition is not the definition of HAZ, and the base metal is changed in this zone.

Answer:

B. It is the area next to the weld where the metal's structure changes due to heat.