Alternative approaches to passivation and cleaning of pharmaceutical equipment

Summary

An intact passive film is essential for the corrosion resistance of pharmaceutical equipment. However, corrosion resistance is not a material property, but depends on the material and environment of the respective corrosion system. Corrosion systems in this environment (pharmaceutical equipment made of stainless steels) are mostly electrochemical in nature. From the laws of this electrochemical nature, it is clear that in an existing corrosion system crevice corrosion always occurs as the first form of corrosion. From these findings, the existing experience is confirmed that for this group of materials, anything that is not an intact passive film can constitute a crevice. It follows from this: Cleaning, i.e., the removal of these potential gaps, is of decisive importance for an effective passive film to build up in the first place. Therefore, it is obvious to use electrochemical investigation methods to classify and optimize passivation solutions.

Introduction