Corrosion Flashcards
Shallow indentations or deep cavities of small diameter that form on metal surfaces
Pitting Corrosion
Corrosive attack along the grain boundaries of a metal alloy
Intergranular Corrosion
Dissimilar metals in contact in a corrosive medium, such as salt water
Galvanic Corrosion
Lifting up of the metal surface caused by the force of expanding corrosion products occurring at the grain boundaries just below the metal surface
Exfoliation Corrosion
Difference in concentration of the electrolyte or the active metal on the anode and cathode
Crevice Attack
Threadlike filaments that form under organic substances such as paint film
Filiform Corrosion
Metal fractures caused by the combined effects of corrosion and stress applied in cycles to a part
Fatigue corrosion
Slipping movement between two mating metal surfaces
Fretting Corrosion
Fungus growths on the sealing materials of integral tanks
Microbiological corrosion
Uniform etching of the metal surfaces
Direct surface attack
white to gray powder
Aluminum alloy
White, powdery , snowlike mounds
magnesium alloy
reddish brown oxide (rust)
Low alloy steel
rough surface, red, brown, or black stain
Stainless steel
highly corrosion resistant
Titanium alloy
white powdery deposit to brown or black molting of the surface
Cadmium
blistering of plating due to rusting and lifting
chromium
green powdery deposit
Nickel base alloy
blue or green blue powdery deposit
Copper base, brass, bronze
brown to black film
silver
deposits cause darkening of reflective surfaces
Gold
whisker like deposits
Tin
