Flow-accelerated corrosion is primarily associated with which aging effect?

• A. Neutron irradiation of materials.
• B. Wall thinning due to corrosion, erosion, or flow-accelerated corrosion.
• C. Radiation-induced embrittlement.
• D. Fatigue failure from thermal cycling.

Answer: (B)

Flow-accelerated corrosion is the thinning of metal walls caused by chemical and mechanical wear from flowing water, especially under high flow, temperature, and oxygen conditions. In power plant piping, this means the protective oxide layer is compromised and material is removed more quickly than would occur by corrosion alone, leading to reduced wall thickness over time. This directly describes an aging mechanism where structural integrity declines due to flow-enhanced material loss, rather than changes from radiation or from cyclic loading. The other options involve neutron irradiation or fatigue, which are different aging processes driven by radiation effects or mechanical cycling, not flow-driven wall thinning. So the best answer is the description of wall thinning due to corrosion, erosion, or flow-accelerated corrosion.