Biofilm on a steel surface [SEM, SE]

   During application, water based metal working fluids undergo drastic changes caused by physical influences and chemical reactions. Microbial induced chemical reactions are a major problem for already prepared working emulsions and water based metal working fluids in general are an excellent growth medium for microorganisms like fungi and bacteria. Certain compounds of the metal working fluid are used as food source and are degraded, finally leading to a loss of required characteristic features of the metal working fluid.

In particular, biofilms which were not removed during cleaning will cause a rapid recolonization by microorganisms. In general, dead zones and tubing systems represent areas where an effective cleaning is not possible. Within the previous project “KomiK I” active antimicrobial coatings on the basis of silver and/or copper were developed which reduced a microbial colonization of the surface. The effect was demonstrated under a real production situation. Based on these results we want to extend the impact on the microorganisms by using additional active metal agents in this new project.

The here described research project (15450 N) is funded by the Federal Ministry for Economics and Technology (BMWi) through the German Federation of Industrial Research Association ”Otto von Guericke” e.V. (AiF) from December 1, 2007 to November 30, 2009. Their help is greatly acknowledged.