Stress locked into a member after it has been formed to its final shape is called what?

• A. Resurfacing
• B. Relief
• C. Residual Stress
• D. Reinforced Earth

Answer: (C)

Stresses that remain locked inside a material after it has been formed and brought to its final shape are called residual stresses. They come from nonuniform deformation, temperature gradients during forming or cooling, welding, or other manufacturing steps, and they persist without any external load. These stresses can cause distortion and influence how the member behaves under service, especially with regard to fatigue and crack initiation. In this question, the stress locked into the finished member is residual stress. Resurfacing refers to surface treatment, relief describes reducing or relieving internal stresses, and Reinforced Earth is a construction method, not a term for locked-in stress.