Nitric Acid 62 to 68%

Extra pure NITRIC , removes iron residue & forms an oxide layer that boosts the corrosion resistance of the stainless steel intended to improve the corrosion resistance of parts made from austenitic, ferritic and martensitic corrosion-resistant steels of the 200, 300 and 400 series and precipitation hardened corrosion-resistant steels.
High carbon, high chromium martensitic 440C grades which are selected for high hardness and resistance may be exempt from passivation treatments at the discretion of the procuring activity.

PRECAUTION :
1> Loose iron particles or other foreign particles must be removed or they will appear as rust or stain spots. may become smeared over or imbedded into the surface of corrosion-resistant steel parts.
2> DO avoid chlorides that, in excess, can cause a harmful flash attack. When possible, use only a good grade of water containing less than about 50 parts per million (ppm) of chlorides. Tap water is usually adequate, and in some cases up In several hundred ppm chlorides can be tolerated.

Chlorides: are present in many cleaning agents. This entails risk of pitting corrosion of stainless steel. If a cleaner containing chlorine, chlorides, bleaches orhypochlorites is used it must be afterwards promptly and thoroughly cleaned off.