학술논문

Passivation Level of AISI 316L Aseptic Tank Surface Quantified by On-Site Electrochemical Techniques
Document Type
article
Source
Materials Research. January 2022 25(1)
Subject
On-site cyclic polarization
316L stainless steel
ASME BPE
Aseptic tank
Localized corrosion
Corrosion monitoring
Language
English
ISSN
1516-1439
Abstract
Frequently stainless steel AISI 316L aseptic tanks have their passivity and corrosion resistance properties degraded by biofilm formation and localized corrosion processes. Thereby, maintenance projects are performed to repair the surface in food-grade product contact to obtain an aseptic property as defined by ASME BPE. However, the on-site non-destructive testing are limited to the liquid penetrant examination and the average roughness measurement. The on-site open circuit potential and on-site cyclic polarization measurements were conducted using a portable electrochemical minicell. The level of passivation was quantified on the tank surface, and it was performed before and after the repairing maintenance protocol be made. The results of the on-site electrochemical measurements showed a clear difference between as-degraded and repaired surfaces, indicating a sensible response to aseptic surface inspection. The on-site open circuit potential together with the on-site cyclic polarization were considered an advanced tool to support the maintenance projects of the AISI 316L aseptic surfaces.