an area that is shielded from full exposure to the environment because of close proximity of the
metal to the surface of another material.
Electrolyte A chemical substance containing ions that migrate in an electric field.
Galvanic Series A list of metals and alloys arranged according to their corrosion potentials
in a given environment.
Generalized Corrosion Corrosion that is distributed more or less uniformly over the
surface of a material.
Localized Corrosion This occurs at discrete sites on the metal surface.
Mill Scale The oxide layer formed during hot fabrication or heat treatment of metals.
Passivation A reduction of the anodic reaction rate of an electrode involved in corrosion.
Pitting Corrosion Localized corrosion of a metal surface that is confined to a small area
and takes the form of cavities called pits.
Return Path (Metallic Pathway) This connects the anode and cathode, allowing passage of
electrons, generated at the anode, to the cathode.
, SSPC-VIS 1 Rust Grade A Steel surfaces completely covered with adherent mill scale;
little or no rust visible
SSPC- VIS 1 Rust Grade B Steel surface covered with both mill scale and rust
SSPC-VIS 1 Rust Grade C Steel surface completely covered with rust; little or no pitting
visible
SSPC-VIS 1 Rust Grade D Steel surface completely covered with rust; pitting visible
NACE No. 1/SSPC-SP 5 "White Metal Blast Cleaning"
NACE No. 2/SSPC-SP 10 "Near-White Metal Blast Cleaning"
NACE No. 3/SSPC-SP 6 "Commercial Blast Cleaning"
NACE No. 4/SSPC-SP 7 "Brush-Off Blast Cleaning"
NACE No. 8/SSPC-SP 14 "Industrial Blast Cleaning"
ISO 8501-1 A Steel surface largely covered with adhering mill scale but little, if any, rust