A 0.17 mM NaCl droplet on X100 pipeline steel covered by paraffin oil
is used to simulate the corrosive environment encountered in heavy oil
or bitumen pipelines. The development of corrosion under the droplet
was monitored and explored in two stages. In the initial stage (1 h), the
distribution of corrosion pits was heterogeneous with one area under
the droplet presenting a higher pit density. As the corrosion proceeded
(24 h), the localized corrosion in the area under the droplet with the
higher pit density switched to general corrosion, while the other region
of the droplet continued to pit. The mechanisms driving this new
distinctive corrosion form developed beneath an underoil salty droplet
on X100 pipeline steel are explained.Applied Science, Faculty ofMaterials Engineering, Department ofReviewedFacultyGraduat