What is the primary purpose of normalizing a part after welding?

• A. To relieve internal stresses developed with the base metal
• B. To increase hardness
• C. To improve surface finish
• D. To reduce weight

Answer: (A)

Normalizing after welding is about managing the stresses introduced by welding and refining the metal's structure. When you weld, the weld metal and surrounding base metal heat and cool at different rates, leaving residual internal stresses and a coarser grain in the heat-affected zone. Heating the part above the transformation temperature and letting it cool in air produces a finer, more uniform grain structure and relieves these stresses. The result is improved toughness, reduced distortion, and lower risk of cracking in service. This isn’t primarily about increasing hardness, improving surface finish, or reducing weight, which are not the main goals of normalizing.