PdO-TiO2 and RuO2 - Ti02 coating can obviously improve the corrosion resistance of TC4 titanium alloy, especially the crevice corrosion resistance. Toshio Fukuzuka describes the preparation methods and protective properties of PdO - Ti02 coatings. The usual method is: using the brush solution of chlorine containing chemical fertilizers and titanium trichloride applied to titanium alloy surface, after drying by 500 - 700 degrees of thermal oxidation of tens of minutes, eventually making it into oxide coating. The operation is repeated several times until the coating weight gain reaches 1g / m2. The mass ratio of PdO and TiO2 in coatings is usually 7:3. The coating makes the TC4 titanium alloy form a very light adhesive force, and its know-how is in the preparation of the solution. Acidic solution will corrode the surface of TC4 titanium alloy and form a layer of hydride, which can be oxidized and decomposed by high temperature. This is the key to obtain good adhesion of oxide coating.

The corrosion rate of pure titanium in 70% hydrochloric acid, sulfuric acid and phosphoric acid and pure titanium with PdO-TiO coating can be seen: PdO - Ti02 coating can obviously improve the candle resistance of titanium in hydrochloric acid, sulfuric acid and phosphoric acid towel. Especially phosphoric acid, the corrosion rate of coating is stable, and almost wood increases with the increase of acid mass fraction. The crevice corrosion resistance of the coating is also shown in tabular form. For boiling Sodium Chloride Solution, the crevice corrosion of the coated sample is not allowed under the conditions of 3 kinds of NaCl mass fraction (each mass fraction is adjusted to 3 PH value). Even in 12% Sodium Chloride Solution, crevice corrosion occurs when the mass fraction reaches 47%. Crevice corrosion occurs only in 42% boiling magnesium chloride solutions. However, crevice corrosion occurred in all of the above solutions.