What is the primary reason for performing a heat treatment after welding?

Performing a heat treatment after welding is primarily aimed at obtaining desired material properties. Welding can induce stresses, change microstructures, and alter mechanical properties in the heat-affected zone (HAZ) and the weld metal itself. By applying heat treatment, the material can be conditioned to improve its ductility, toughness, and strength, addressing any hardness or brittleness that may have developed during the welding process.

This process can involve techniques such as annealing, normalizing, or stress relieving, each intended to manipulate the material's structure to achieve the specifications required for its intended application. Thus, the key outcome of heat treatment is the enhancement of material performance, making it a crucial phase in the overall welding procedure.