Abstract
To clarify the effects of cathodic protection on cavitation erosion in seawater experiments were conducted. Four metallic materials were used in conjunction with using a cavitating jet erosion apparatus. They were pure copper C1100BD-H, stainless steel SUS316; second type titanium TB340C and the third, titanium alloy Ti-6Al-4V. The results were as follows: (1) The mass loss of each metallic material decreases remarkably with the increase of the cathodic current. The current density of the effective protection is approximately 0.07 [A/cm2] under test conditions. (2) Under cathodic protection the cushioning effect of the protective film of the adhesion product decreases with the mass loss, as do the hydrogen gas effect and anticorrosive effect, etc. (3) Cavitation erosion resistance in seawater, and under cathodic protection, can be evaluated in terms of macro hardness (HV). These are improved when the average hardness or the cathodic current increases.
