Ru-Based Bond Coats Used for High Temperature Applications

Abstract:

The main objective of this work is the development of new Ru-based Bond Coats (BC) as part of Thermal Barrier Coating Systems (TBC).So far, Ru-based systems have not been investigated in detail. We investigate the possibility of replacing the traditional materials used as BC, with Ru-based alloys. They are important candidats because RuAl has the same structure as NiAl, has properties superior to those of NiAl at high temperatures and last but not least, Ru is much cheaper than Pt.We have prepared a RuAl 50/50 at% alloy in an induction furnace which was subsequently subjected to oxidation in an electric furnace, in air, at 1100°C, for 10h.The alloy was analysed before and after oxidation using advanced microscopy techniques (SEM, TEM).The challenge of this research is to obtain an adherent and uniform layer of alumina after oxidation. The results so far suggest encouraging results.

• Periodical: Advanced Materials Research (Volume 1114)
• Pages: 229-232
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1114.229
• Online since: July 2015
• Authors: Amalia Soare*, Ioana Csáki, Cristina Oprea, Sorin Soare, Cristian Predescu, Mirela Sohaciu
• Keywords: High Temperature Oxidation, RuAl Alloys, Superalloys, Thermal Barrier Coatings

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