Titanium has good stability in highly corrosive hot water containing chlorides and sulfides, so it has been widely used as a cooling tube for heat exchangers in thermal power plants. After replacing the copper-nickel alloy tube with a thin-walled titanium tube, not only the service life is greatly improved, but also the overhaul time is greatly reduced, and the economic benefit is remarkable.
Titanium and titanium alloys have good corrosion resistance and are also used in the anti-corrosion lining of chimneys.
Commercially pure titanium is a thermodynamically unstable metal. If Ti2+ can be produced by dissolution, the standard electrode potential for titanium ionization is −1.63 V, which makes titanium soluble in water and releases hydrogen. However, in a variety of corrosive media, titanium has very strong corrosion resistance, which is due to the great passivation effect of titanium. Its passivation degree exceeds that of cobalt, nickel, and stainless steel. It has excellent corrosion resistance in many active media, especially in oxidizing media, chlorine, and chloride media, but titanium has poor stability in sulfuric acid and hydrochloric acid.
In order to solve the problem of poor corrosion resistance of conventional titanium and titanium alloys to reducing media such as sulfuric acid and hydrochloric acid, adding molybdenum (10% to 32%) to titanium alloys can greatly improve the corrosion resistance of titanium alloys to reducing media. The higher the molybdenum content, the better the corrosion resistance, but the more difficult it is to smelt and process. The main performance is the strengthening of the alloy, which affects the application of the alloy to a certain extent. Titanium-molybdenum alloys are more suitable than pure titanium for corrosion protection of steel chimneys. Titanium-molybdenum alloys of Ti-20MO and above can meet the requirements, and because of their strong chloride resistance, they are especially suitable for power plants using seawater desulfurization. The higher the molybdenum content, the better the corrosion resistance, but the more difficult it is to smelt and process. The main performance is the strengthening of the alloy, which affects the application of the alloy to a certain extent. Titanium-molybdenum alloys are more suitable than pure titanium for corrosion protection of steel chimneys. Titanium-molybdenum alloys of Ti-20MO and above can meet the requirements, and because of their strong chloride resistance, they are especially suitable for power plants using seawater desulfurization.
Shaanxi Etermetal Co., Ltd. is a professional titanium tube supplier. We can provide you with various grades and standards of titanium tube products. If you have any questions or needs related to products, welcome to consult and cooperate!
