Palladium and tantalum aluminide coatings for high-temperature oxidation resistance of titanium alloy IMI 834

Abstract

The present article explains the efforts made in developing new protective coatings based on palladium, tantalum, and aluminum with considerably improved oxidation resistance for effective protection of titanium alloy IMI 834. Systematic characterization was carried out on as-prepared as well as oxidized coatings and these results are presented. The performance of new coatings was evaluated by generating weight-gain data as a function of time followed by detailed characterization in order to confirm the ability of the coatings to prevent oxidation and alpha-case formation. The results showed that tantalum aluminide and simple aluminide coatings exhibit improved oxidation resistance when compared to palladium aluminide. Finally, the advantages of developed new coatings and the necessity of their use in modern gas turbine engines that allow the alloy to be used safely at high temperatures, which in turn would enhance the efficiency of gas-turbine engine-compressor sections, will be stressed.

RETRACTED: The effect of titanium alloy composition in synthesis of Titania nanotubes

“…The mechanical properties of IMI 834 and other titanium alloys are dependent on variables such as alloy chemistry, manufacturing methods and environmental conditions during the service, since these variables greatly influence the microstructure, which inherently affects their properties. Extensive research on the titanium alloy IMI 834 was carried out under simulated aeroengine conditions by Gurrappa [17][18][19][20][21] and developed high performance and smart coatings to increase its life during service [22][23][24][25][26][27][28][29]. Good amount of research work has been carried out on pure titanium and their alloys like Ti 64, TiNb, TiAl etc.…”

On the cyclic hot corrosion behaviour of atmospheric plasma sprayed Lanthanum Zirconate based coatings in contact with a mixture of sodium sulphate and vanadate salts: A comparison with the traditional Ysz duplex and NiCrAlY coated samples

“…Simultaneously, basic dissolution of oxides occurs, for example, Cr 2 O 3 may be dissolved by the following reaction [27]:…”

The Selection of Materials for Marine Gas Turbine Engines

“…The protective coatings allow the marine gas turbine engines to operate at varied temperatures and enhance their efficiency by eliminating failures during service. Research in this direction has resulted in design and development of smart coatings which provide effective protection to the superalloy components for the designed period against type I, type II hot corrosion and high temperature oxidation that are normally encountered in gas turbine engines which in turn enhances the efficiency of gas turbine engines considerably [14][15]. This is a major developmental work in the area of gas turbine engines used in aero, marine and industrial applications.…”

“…This is a major developmental work in the area of gas turbine engines used in aero, marine and industrial applications. Unlike the conventional / existing coatings, the smart coatings provide total protection to the superalloy components used in aero, marine and industrial applications by forming appropriate protective scales like alumina or chromia depending on the surrounding environmental conditions [14][15].…”