Titanium in reducing inorganic acids and some organic acids, because it can not maintain a passive oxide film, the corrosion rate is relatively fast, adding corrosion inhibitor is an effective measure to reduce corrosion. Corrosion inhibitors include precious metal ions, heavy metal ions, oxidizing inorganic compounds, oxidizing organic compounds, and complex organic corrosion inhibitors. The price of precious metal ions is very high, and it is rarely used as a corrosion inhibitor for reducing inorganic acids; heavy metal ions Cu2 + and Fe2 + ions have a very obvious corrosion inhibitory effect, but they need to reach a critical concentration before they can function; oxidizing inorganic compounds Nitric acid, chlorine gas, potassium chlorate, potassium dichromate, potassium permanganate, hydrogen peroxide, etc .; oxidizing organic compounds include nitro or nitroso compounds, nitrogen compounds, anthracene or anthraquinone derivatives, etc .; complex organic Corrosion inhibitors are different from oxidizing organic compounds. They can play the role of corrosion inhibition at any concentration. There is no concept of critical concentration, but the effect is different.