Overview

The Basics of Cavitation

Cavitation is a type of surface degradation that occurs in hydraulic systems and mechanical components exposed to rapid changes in fluid pressure, resulting in the formation and collapse of vapor bubbles on the surface. This phenomenon is commonly observed in systems such as pumps, valves, and propellers, where high-velocity fluid flow causes pressure variations and subsequent material damage. This failure mode is considered a wear mechanism because it results in loss of material, but it’s unique in that it occurs in the presence of a moving liquid and doesn’t require contact between two components.

Cavitation can be defined as the loss of material from a surface due to the formation, growth, and collapse of vapor bubbles in a fluid medium, causing high-speed microjets and shock waves that lead to the progressive removal of material through fatigue and erosion mechanisms. Synonyms for cavitation wear include cavitation erosion or damage, and cavitation-induced wear.

Several variables can influence the occurrence and severity of the wear mechanism in mechanical systems. These variables include:

Fluid Properties: The viscosity of, vapor pressure, and temperature of the fluid medium can affect the formation and collapse of vapor bubbles, influencing the extent of the failure mode.
Operating Conditions: System parameters such as fluid flow velocity, pressure variations, and turbulence can impact the severity of this form of wear.
Component Geometry: The shape and design of the components can influence the flow patterns and pressure distribution, affecting the likelihood of cavitation wear.

To minimize the occurrence and severity of cavitation in mechanical systems, various strategies should be employed, including:

Component Design: Optimize the design of components to reduce flow turbulence, pressure variations, and the formation of vapor bubbles. Streamlined shapes and gradual changes in flow cross-section can help reduce the likelihood of wear.
Operating Conditions: Adjust system parameters, such as fluid flow velocity and operating pressure, to minimize pressure variations and turbulence. Lowering temperature may also prevent bubble formation.
Surface Treatment: In edge cases, coatings can help to reduce the failure mode or slow down the rate of damage, extending the useful life of a component. Using harder and stronger materials will also reduce damage rates. However, material changes and coatings will rarely prevent this wear mechanism altogether.

Armoloy's Solution to Cavitation

Armoloy offers multiple metal surface treatments with varying levels of protection from the common causes of metal failure. Offering both broad-spectrum and industry-specific applications, our protective metallic coatings add significant value through increased performance and decreased revenue losses from unplanned maintenance and downtime.

Our protective coatings ensure a thin, precise coat that won’t impact production, but will improve surface hardness and prevent environmental defects. Beyond increasing wear life, Armoloy tailors our metallic coatings based on the specific requirements of your application and industry.

Beyond the Lab: Metal Failures in Narrative Form

Other Metal Failure Modes

Other common metal failures include:

Cavitation can also result from, or be a precursor to, other potential metal failures

Erosive Wear

Rolling Contact Fatigue

Pitting Corrosion

Chemical Resistance

Eliminate metal failure from your operations. Meet our group of curious, innovative engineers and learn how we can help improve your industry with science-based solutions.

Coating Calculator Request a Sample

Cavitation