Citric Acid Passivation
An environmentally friendly method for iron removal and passivation of stainless steel surfaces using organic citric acid solutions. Chemical complexation dissolves free iron particles and promotes the formation of passive protective layers.
Citric acid passivation removes free iron particles from the stainless steel surface, which would otherwise act as rust nuclei. This allows the protective chromium oxide layer to form undisturbed. For welding, this means: the weld and heat-affected zone are clean and corrosion-resistant after treatment. It's important to rinse and dry the parts thoroughly before welding to prevent acid residues from entering the weld. The treatment itself is not critical as long as you don't let the solution sit for hours and rinse well with water afterwards.