Corrosion Flashcards
1
Q
Cavitation and galvanic corrosion on a propellor, showed a picture and had to look at damage and explain it.
A
This is the result of formation of small vapor bubbles (cavitation) in the water in regions where the flow conditions produce low pressures and subsequent violent collapse of these bubbles on the surface of the metal in neighbouring areas where the local pressure is higher.
Galvanic corrosion is when to dissimilar metals come into contact with each other. One will act as a cathode and the other as an anode. this speeds up the rate of corrosion.
2
Q
Picture of shaft with pitting under the seal
A
Stagnant water that has removed all the oxygen and starts to attack the shaft
