The following statement is true or false: Peening is performed prior to preheating the structure to be repaired.

The following statement is true or false: Peening is performed prior to preheating the structure to be repaired.

• A. True
• B. False
• C. Not Applicable
• D. Not Enough Information

Answer: (A)

Peening is a surface treatment that intentionally creates compressive residual stresses on the metal. In repair work, these compressive stresses help oppose the tensile stresses that develop as the material is heated and then cooled, reducing the chance of crack initiation and propagation at the weld and heat-affected zone. Performing peening before preheating means the surface is already in compression when the heating cycle begins. Those compressive stresses help keep cracks from opening as the metal heats, expands, and then cools. If peening were done after preheating, the heat could relieve or lessen the introduced compressive stresses, making the peening less effective when the material is under the thermal and mechanical demands of welding and cooling. So, peening prior to preheating best supports controlling residual stresses and improving weld integrity in repair scenarios.

Peening is a surface treatment that intentionally creates compressive residual stresses on the metal. In repair work, these compressive stresses help oppose the tensile stresses that develop as the material is heated and then cooled, reducing the chance of crack initiation and propagation at the weld and heat-affected zone.

Performing peening before preheating means the surface is already in compression when the heating cycle begins. Those compressive stresses help keep cracks from opening as the metal heats, expands, and then cools. If peening were done after preheating, the heat could relieve or lessen the introduced compressive stresses, making the peening less effective when the material is under the thermal and mechanical demands of welding and cooling.

So, peening prior to preheating best supports controlling residual stresses and improving weld integrity in repair scenarios.