Problems and solutions of titanium alloys in the use of ships

Crevice corrosion
Corrosion problem: There are small gaps in parts such as detachable connectors (flanges, threaded connections, etc.) used in ships, and there will be aggressive high concentrations of chloride ions and fluoride ions in the gaps, which requires titanium alloys in seawater. It has good resistance to high temperature crevice corrosion in the environment. In titanium alloy heat exchangers and seawater desalination equipment, the working environment is 90 ~ 250 ℃, and the pH value of the medium is 1.5 ~ 4.0 (especially in salt and kerosene deposits), and its crevice corrosion is very deadly.
Anti-corrosion measures:
(1) Adding Pd and Ru elements to titanium alloys can effectively improve the crevice corrosion resistance of titanium alloys.
(2) Perform surface treatment containing Ru/Pd on the surface of titanium alloy, such as infiltrating Ru/Pd element on the surface of titanium alloy or performing micro-arc oxidation to form oxide containing Ru/Pd element on the surface of titanium alloy. In order to reduce the cost of surface treatment, gradient coatings containing Ru/Pd elements can also be prepared on the surface of titanium alloys.
(3) When the cathodic protection technology is used to protect the steel structure, the potential is between -800 mV and -1050 mV to avoid hydrogen supersaturation and hydrogen-induced cracking of the titanium alloy.
feihongalloys.com