The influence of increased air content of the cavitating liquid (disti
lled water) was studied in a rotating disk test rig. A rise in the tot
al air content (including dissolved and entrained air) of the water in
the undersaturated range resulted in bubble collapse cushioning and r
eduction of cavitation damage. When the water was oversaturated with a
ir, large air bubbles formed and cavitation damage was drastically red
uced, probably due to both bubble collapse cushioning and shock wave a
ttenuation.