In natural environments, microbes attach to engineering materials and
colonize the surfaces to produce biofilms. Biofilms mediate the intera
ctions between surfaces and environment resulting in serious energy lo
sses, reduced equipment performance and corrosion failures in several
defence and industrial systems. The chemical processing industry, oil
and gas industry, power generation industry and the defence services h
ave acknowledged the prevalence of biocorrosion in their operating sys
tems. Microbial activity seemed to be involved in most of the cases of
failure of the systems where mild steel, iron and copper alloys were
used. The present paper incorporates the data obtained in respect of t
hree different corrosion behaviours of structural materials viz., an e
asily corrodable surface (mild steel), a corrosion resistant surface (
304 stainless steel) and a complex corrosion behaviour (copper)..Micro
biological and electrochemical methods have been used to study the int
erfacial properties of metallic surfaces covered with biofilms. The bi
ologically conditioned interfaces have been characterised by selecting
suitable parameters in metal biofilm systems. The biofilm/passive lay
er interactions have been interpreted on the basis of charge transfer
and diffusion controlled reactions taking into account adsorbed reacti
on intermediates or products.