That “welding brush” on stainless steel isn’t just cleanup — it’s metallurgy. Stainless steel resists rust because chromium in the alloy forms a thin, invisible chromium-oxide passive layer when exposed to oxygen. Welding disrupts that layer by adding heat, oxides, and surface contamination. A dedicated stainless steel wire brush is used to remove heat tint, slag, and surface oxides without embedding carbon steel particles. If you use a regular steel brush, you can smear free iron into the surface — and that iron will rust first, creating corrosion that looks like the stainless itself is failing. Key engineering reasons this matters: • Prevents galvanic corrosion from embedded carbon steel • Restores a uniform surface for passivation • Reduces pitting and crevice corrosion long-term • Improves weld integrity in food, medical, and chemical systems In critical applications, brushing is often followed by chemical passivation (nitric or citric acid) to fully rebuild the chromium-oxide l...