Passivante P


The “P” passivating solution is a nitric acid-based liquid product conform to ASTM A380 and has been designed to increase the resistance to corrosion and ensure that the passive film of chromium oxide, typical of 300-series stainless steels, is restored after adequate pickling. It can also be used after an electropolishing treatment to remove any marks that have formed.

Instructions for use

The product is to be used as is.

Chemical treatments in general are not effective if oils and greases are not first removed. It is advisable to pre-treat the surfaces with a liquid degreaser; good degreasing is an essential requirement to obtain a good result.

Application is normally by immersion in PP, PVC or stainless steel tanks or by spraying and a fume extraction system has to be installed [it is advisable to use PTFE (Teflon) heating elements to heat the solution].

The treatment time varies depending on the temperature at which you operate: at room temperature, a minimum time of 60 minutes is recommended; at 50-60°C, a minimum time of 30 minutes.

After passivating the pieces, give them another good wash at high pressure. A final wash with demineralised water allows obtaining an excellent result.

If you want to significantly increase the resistance to corrosion, apply POLINOX B PROTECT after passivation, which optimises the formation and composition of the same passivation layer increasing the resistance to corrosion of stainless steel.

The ready-to-use “P” passivating solution has a density of 1.3.

The “P” passivating solution works well at room temperature, but can also be used hot (70°C).

Precautions for use

Use appropriate PPE and follow the instructions on the safety data sheet.


The washing water is acidic and may therefore not be drained directly, but has to be neutralised and decanted.

Industrial wastewater may be drained only after authorisation by the competent authorities. Delmet can supply manual or automatic equipment for this type of treatment.

Available sizes

  • “P” passivating solution - pack of 10 kg (PC00019)
  • “P” passivating solution - pack of 30 kg (PC00022)
  • “P” passivating solution - pack of 1000 kg (PC00022)

Download the technical sheet in PDF format

Download the technical sheet in PDF format

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