Siberian scientists have developed the technology that increases corrosion resistance of titanium by several orders. Being strong, lightweight and corrosion resistant, titanium finds wide application in the aerospace industry and medicine. Additionally, it causes little or no irritation when implanted into the body.
"According to the level of corrosion resistance, our alloys are tenfold superior to special acid-resistant stainless steels. That's why, despite the fact that the price of this alloy is higher (3000 roubles against 900 per kilogram ), in terms of good value for money it is more cost efficient", says Vitaly Samoilenko, NSTU engineer.
Russian physicists have developed the technology of titanium welding with corrosion-resistant coatings of tantalum and niobium. This technology combines powder metallurgy known in ancient Egypt and modern particles accelerator whose beam can melt even fine particles of titanium and fragments of refractory materials.
The technique works as follows: scientists cover a titanium plate with a thin layer of powder consisting of microscopic particles of titanium, tantalum and other refractory metals. After that, the electron beam produced by the particle accelerator ELV-6 passes through it. This particle accelerator was specifically created for such purposes in the INP SB RAS.
"The electron beam penetrates into the powder and melts titanium particles and the surface of the titanium plate. Tantalum particles are wetted with titanium and dissolve in it like sugar in water. This way we obtain a deposited layer which increases the corrosion resistance of the source metal in almost a hundred times," adds Mikhail Golkowski, senior researcher at the INP SB RAS.
According to the scientist, such "puff" plates can be processed and used in the metallurgical industry in the same way as conventional titanium or other metals: only the most extreme situations can crack or damage the protective layer.
Sheets of this material can be deformed in different ways to obtain the designs of any shape, thickness and size.
Using this technology, Russian physicists have developed several alloys of titanium and refractory metals which have a record resistance to hydrochloric, sulfuric and nitric acids. What's important, they have a relatively low cost.
As noted by Novosibirsk scientists, the products made of such materials will be more lightweight than similar vessels made of acid-resistant stainless steel. It will help them to quickly penetrate into industrial enterprises and chemical laboratories.
In the photo: 1. titanium plate with deposited anti-corrosion layer; its thickness is 12.5 mm. 2. cross-section of the material with the welded layer after rolling. The initial thickness of the material is 12.5 mm, the thickness after rolling is 3 mm.