What passivation is
Passivation is a chemical treatment applied after fabrication (especially after cutting, welding or machining) that removes surface contamination — free iron particles from tools, for example — and helps the chromium oxide protective layer (see our corrosion resistance guide) form properly and consistently across the whole surface.
Why fabrication can compromise the surface
Cutting, grinding and welding can embed tiny particles of ordinary (non-stainless) tool steel into the surface, or heat-affect the metal near welds — both of which can create localised weak points in corrosion resistance if left untreated.
Why it matters for you as a buyer
A fabricator who passivates welded and machined stainless steel work is taking a genuine quality step that affects long-term performance, particularly at weld points — worth asking about specifically for outdoor or high-corrosion-risk fabricated pieces.
Our approach
We treat fabricated joints and cut edges appropriately as part of our finishing process — ask us directly about this for any welded custom work if it's relevant to your project's exposure conditions.