API 571 Certification (Corrosion & Materials) Practice Test

Which of the following materials is most commonly associated with cavitation?

1. Copper and brass

2. Alloy 825

3. Stainless steel only

4. High-strength alloys

The correct answer is: Copper and brass

Cavitation is a phenomenon that occurs when vapor bubbles form in a liquid and then collapse, leading to shock waves that can cause significant damage to materials. This effect is particularly associated with metals that have relatively low strength and ductility, allowing them to be more susceptible to the forces generated during cavitation. Copper and brass are commonly associated with cavitation damage because they are frequently used in applications involving fluid movement, such as pumps and valves. Their hardness and relative softness compared to other materials make them more vulnerable to the effects of cavitation. The presence of cavitation in these materials can lead to pitting and erosion, requiring careful design and material selection in applications where cavitation is likely. In contrast, other materials like Alloy 825, stainless steel, and high-strength alloys tend to exhibit better resistance to cavitation due to their mechanical properties and inherent corrosion resistance, which help prevent the initiation and propagation of damage from cavitation.