PROTECTIVE LAYERS ON STEEL PARTS GALVANICALLY COMPATIBLE WITH ALUMINUM AND ALUMINUM ALLOYS
Description of the project: Protective layers on carbon and stainless steels, galvanically compatible with aluminum and aluminum alloys, formed using vacuum ion-assisted metal deposition in a mode in which accelerated ions of the deposited metal are used to assist the deposition process.
The development can be used as the basis for an effective technology for increasing the corrosion resistance of aluminum-based structural materials in contact with steel parts and for protecting steel products themselves from corrosion.
It is advisable to use the proposed method for obtaining protective coatings as an alternative to the most problematic galvanic technologies, incl. h. galvanic cadmium plating, which is currently prohibited almost everywhere in developed countries due to the high toxicity of both the metal cadmium itself and its ions formed in the waste of galvanic deposition.
Benefits:
Manufacturability, resource saving and environmental safety of the process of forming protective layers.
Vacuum ion-assisted deposition of metals makes it possible to obtain protective layers with a thickness of ~ 100 nm that are firmly bound to the substrate due to ion mixing at a content of alloying metals in them ~ (2–5) × 1016 atom / cm2. A reduction to one or two of the number of technological operations of preliminary surface preparation of the modified structural materials and the one-stage formation of a coating by the proposed method in comparison with galvanic deposition significantly reduce the duration of the coating formation process and reduce its energy consumption.
Achieved results:
Experimental samples of carbon steel St3 and stainless 12X18H9T steels with protective layers formed by ion-assisted deposition of cadmium and zinc from the plasma of a vacuum pulse arc discharge; results of studies of their galvanic compatibility with samples of aluminum grade A7 and aluminum alloy D16.
Market and consumers:
The field of application of the development is corrosion protection of structures made of aluminum alloys in contact with steel parts, primarily at aircraft building, aircraft repair and shipbuilding enterprises.