Roger Francis

RF Materials offers a wide range of consultancy services in the fields of corrosion and materials. These include examination of corrosion failures and advice on materials selection, corrosion issues and corrosion audits. In addition we offer short corrosion courses, which address some common issues. The chief consultant is Roger Francis, who has over 40 years experience in corrosion engineering, covering a wide range of materials and industries. He has extensive experience of both copper alloys and stainless steels. The full range of materials covers everything from carbon steel to titanium alloys and industries include marine, oil and gas, desalination, chemical and process and mining.


Latest Corrosion Pointer

Galvanic Corrosion 5

Galvanic corrosion in fresh waters is somewhat different to that in seawater or strong brines.  The potentials of common alloys are a little different to those in seawater, but the relative ranking is more or less the same.  However, the lower conductivity of the water (~100X) means that galvanic corrosion is often confined close to the metal junction.  In addition, the low conductivity can mean that current from a remote cathode is greatly reduced.  However, this is also affected by geometry.  Stainless steel is cathodic to copper in fresh waters, but stainless steel pipes have been successfully been joined with copper solder fittings.  Where the area ratio of stainless steel to copper is large, severe galvanic corrosion can occur.  The photograph below shows a badly corroded copper pipe entering a large stainless steel hot water tank.

Badly corroded copper pipe entering a large stainless steel  hot water tank.

Posted on: 21st August 2017

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Image (top left) by Agnieszka