In the reducing inorganic acid and some organic acids, the titanium alloy plate can not maintain the passive oxide film, and the corrosion rate is relatively fast. Adding a corrosion inhibitor is an effective measure to reduce corrosion. Candle retarders include precious metal ions, heavy metal ions, oxidizing inorganic foods, organic compounds of oxidized parts, complex organic corrosion inhibitors, etc. The price of precious metal ions is very high, and it is rarely used as a corrosion inhibitor for reducing the organic acid of the parts; until the metal ion copper is dry and the iron ion has a very obvious corrosion inhibition structure, but it needs to reach a critical concentration before it can work; Oxidizing inorganic compounds include nitric acid, chlorine gas, chloric acid bell, potassium dichromate, potassium permanganate, hydrogen peroxide, etc.; oxidizing organic compounds include nitro or nitroso compounds, nitrogen compounds, etc.; complex organic slow Etching agents are different from oxidizing organic compounds. They can act as corrosion inhibitors at any concentration. There is no concept of critical concentration, but the effect size is different.
Surface treatment is a very effective method to improve the corrosion resistance of titanium alloy plates. The methods of surface treatment include cathodic oxidation, thermal oxidation, nitridation and coating technology. The effects of anodic oxidation, thermal oxidation and Ba Xu layer on the crevice corrosion time of the titanium alloy plate show that the effect of improving the corrosion resistance of the titanium alloy plate by the coating is the most obvious, even better than the corrosion resistance of Ti-0.15Pd .
The anodization of the titanium alloy plate is usually carried out in 5%-10% (NH4) 2sO solution, plus 25V DC voltage for anodizing treatment, the thickness of the anodized film can reach 300-500nm. Anodizing can effectively remove the iron contamination on the surface, effectively extend the passivation time of the titanium alloy plate, and prevent the hydrogen absorption caused by the iron contamination. Therefore, foreign regulations require that all titanium equipment must be anodized. In order to improve the effect of anodizing, the anodizing solution uses sodium platinum to replace ammonium sulfate, so that the effect of corrosion resistance is better.
Titanium alloy plates can be thermally oxidized in the air into rutile-type thermal oxidation strands that are thicker than anodic oxide films and have high crystallinity, and their corrosion resistance is superior to anodic oxide films. The thermal oxidation strands of the titanium alloy plate are made at a temperature of 600-700°C and a time of 10-30min. If the temperature is too high or the time is too long, the effect is not good.
The coating layer of the titanium alloy plate is best for removing the layer. The palladium-containing coating is usually an oxide coating or a lead alloying coating. The typical preparation method of palladium oxide coating PdO-T102 is to apply PdCL4 and TiCL3 solution to the surface of the titanium alloy plate and heat it at 500-600 ℃ for 10-50 min, which can be repeated several times to make the coating thickness reach 1g /M2 or more. The rivet alloying Xu layer is first deposited by electroplating or vacuum deposition of a very thin layer, and the surface alloying treatment technology such as laser remelting surface or ion implantation is carried out. Its adhesion and corrosion resistance are superior to the oxidation coating.
Baoji Hongyada Nonferrous Metal Material Co., Ltd.
Address: Xuguang Industrial Park, Baotai New District, High-tech Zone, Baoji City
Contact: Zhang Hongbin
Mobile phone: 13809171560 (same number on WeChat)
Electricity: 0917-3854158
E-mail: hongyadajinshu@163.com
Skype: carrolyn851
Q Q：379855550 476413451
Website: www.hydtitanium.com