What may be used to remove corrosion from highly stressed steel surfaces?

• A. Slag removal
• B. Sanding
• C. Fine-grit aluminum oxide
• D. Wire brush

Answer: (C)

Cleaning corrosion from highly stressed steel surfaces requires an abrasive that removes the corrosion film without compromising the surface integrity. Fine-grit aluminum oxide fits this need because it removes corrosion in a controlled, uniform way, producing a smooth finish that helps prevent stress concentrations that can lead to fatigue cracks. It achieves material removal without the excessive aggressiveness of coarser methods, which can gouge the surface or alter dimensions, or the risks associated with wire brushes, such as roughening or leaving behind loose particles. Slag removal is more related to welding operations and not ideal for preparing a cleaned, high-strength steel surface for coatings, while sanding can generate heat and remove more material than necessary. Fine-grit aluminum oxide provides the right balance for safe, effective corrosion removal on highly stressed steel.