Corrosion is the destruction of metals through reaction with compounds in their environment. It is a natural process because compounds such as oxides, sulphides and chlorides are formed and these are stabler than pure metals.
Electronic circuits and components are omnipresent in our environment. Until recently, the thousands of soldered joints that an electronic circuit contains were made with products that contained lead, an element that is highly toxic.
Because of the introduction of RoHS regulations that forbid the use of lead in electronic circuits, it has been necessary to develop other technologies, such as ImmAg, a surface coating using silver.
This change has had a great impact on the susceptibility of electronic components to corrosion, not only in more aggressive industrial environments such as paper manufacturing and petrochemical plants but also in urban environments.
In any urban atmosphere various corrosive gases such as SO2, ozone etc. are present in sufficient amounts to damage some of the thousands of soldered joints and components in a sophisticated electronic device and to cause its complete failure.
Diagnosis and Evaluation of Levels of Corrosion
To determine the seriousness of the problem corrosion coupons consisting of copper and silver strips are installed in the area to be assessed (always in closed spaces) for 30 days. These are known as Environmental Corrosion Coupons (ECC).
During this period the corrosive gases form a film of oxides, sulphides etc. on the metal. The thickness of this layer of corrosion can be related to a scale that indicates the level of corrosiveness in a control room, data processing centre, etc.
All tests are carried out, according to accepted international standards, in the Bioconservacion laboratory, which has the necessary equipment to carry out corrosion coupon (ECC) testing on exposed coupons.
- ASTM B 825-02 ‘Standard Test Method for Coulometric Reduction of surface Films of Metallic Samples’
- ISA-S71.04-2013’Environmental Conditions for Process Measurement and Control Systems: Airborne Contaminants’
Once the corrosive gases present in the atmosphere have been correctly characterised and diagnosed with the corrosion coupons, Bioconservacion can supply a comprehensive solution to the problem which includes everything from the most suitable means of absorption to the filtration systems necessary.
Once the solution proposed by Bioconservacion has been implemented, it can be verified through a second exposure of Environmental Corrosion Coupons.