The current paper investigates effects of various surface treatment techniques such as grinding, garnet blasting, and shot peening on the corrosion rate and behavior of austenite stainless steel of type AISI 316 Ti. The exposure to different corrosive solutions usually accompanying the coastal and industrial environments (sodium chloride and ferric chloride), as well as a combination of the two was considered. The corrosion behavior of AISI 316 Ti under these test conditions was investigated using immersion tests and electrochemical impedance spectroscopy together with optical scanning electron microscopy, in order to observe and to assess the changes in the surface configuration and topography such the shapes, distribution, and dimensions of the resulting pits. The presented results clearly show the relatively higher corrosive effect of ferric chloride, and the increased corrosion rate under greater surface roughness values, which imply greater real surface area and capillarity effects.

In the current study, the material corrosion behavior and degradation of a closed-loop copper piping systems were investigated taking temperature and flow parameters into consideration. To simulate the practical environment conditions, two identical copper closed-loop piping systems were constructed with three types of joints. Both systems were filled with 3% sodium chloride solution and run for about eleven months period. They were heated to a temperature of 80°C for eight hours a day and for 5 days a week. Outside that heating period, systems were maintained at room temperature (23± 2°C). Within such a heating interval, the contained solution for one system was kept in stagnation condition while it was flowing at input velocity of 0.27 m/s for the other. For both systems, the corrosion was then assessed and quantified using different evaluation techniques: Potentiodynamic test, Pourbaix diagrams, light microscope and scanning electron microscopy (SEM). The experimental results confirmed a diverse significant influence of solution flowing conditions on the damage of copper pipes.