This image represents the power of bubbles – and the testing process we use to measure it.

Cavitation erosion is caused by the implosion of gas bubbles on a surface, resulting in damage and material loss. The picture on the left shows the effects of cavitation on a nickel sample, taken at hourly intervals over an 8-hour period.

At nC2 we’re undertaking a programme of cavitation testing to examine the effect of binders in cobalt chrome on its cavitation resistance. We’re carrying out this work to ASTM G32 ‘Standard Test Method for Cavitation Erosion Using Vibratory Apparatus’, exposing samples to cavitation and interrupting the test on an hourly basis to measure mass loss. In order to conform to the standard we compare our equipment using a nickel alloy like the one shown.