Keywords
Citation
(1998), "Nickel-base superalloy", Aircraft Engineering and Aerospace Technology, Vol. 70 No. 5. https://doi.org/10.1108/aeat.1998.12770eab.020
Publisher
:Emerald Group Publishing Limited
Copyright © 1998, MCB UP Limited
Nickel-base superalloy
Nickel-base superalloy
Keywords Alloys, Composite materials, Nickel, Tungsten
A nickel-base superalloy that can, reportedly, be used as the matrix material for tungsten wire-reinforced metal matrix composites is under development by researchers Jonathan A. Lee at NASA's Marshall Space Flight Centre, Alabama, and Pat Salvail at IIT Research Institute, Chicago, Illinois. The alloy is said to be similar in composition to Waspaloy except that it contains 2-4 per cent tungsten while Waspaloy contains no tungsten.
The composite is being developed for advanced gas turbine engines and other applications that operate at temperatures to 1,090°C (2,000°F). The modified chemical composition is formulated to retard interfacial chemical reaction and elemental interdiffusion between the matrix and tungsten wire. As a result, high-temperature stability and resistance to thermal fatigue are said to be increased.
Test samples made of tungsten wire reinforced composites using both the modified-alloy and Waspaloy as matrix materials were annealed in vacuum at a temperature of 1,090°C for 48 hours, then examined via scanning electron microscope. In the Waspaloy matrix composite, a 3.5µm thick reaction zone was formed by interdiffusion, whereas no reaction zone was seen in the modified alloy composite.
For further details contact Harry G. Craft Jr, Technology Transfer Officer, Marshall Space Flight Centre, Alabama 35812. Tel: +44 1 800/872-6272.