Chemical Vapor Aluminizing (CVA) is based on the CVD process and is used for the production of diffusion aluminide coatings for high temperature applications. In the 900 - 1050 °C process, aluminum diffuses into the substrate to produce intermetallic compounds – aluminides.
The CVA process is designed to create homogeneous aluminide diffusion layers with controlled thickness, aluminum content and structure on special high temperature nickel alloys. Both low and high-activity aluminides can be deposited on internal and external areas of components. Besides simple aluminides, the Bernex™ CVA process is capable of delivering precursors for the deposition of complex coatings with the addition of Cr, Si, Co, Hf, Y and other elements.
The aluminides offer remarkable resistance to high temperature oxidation and corrosion. Therefore, they are suitable for blades protection in the hot section of turbines. The Bernex™ CVA is an advanced technology that offers an environmentally friendly, better-performing alternative to traditional pack, out of pack and slurry technologies. In addition, the Bernex™ CVA guarantees:
- Environmentally friendly processes, not generating waste powders
- Precise control over the deposition process
- Possibility to coat internal cooling channels
- Uniform coating thickness over large areas
- Possibility to produce multi-material coatings
- Low surface defects density