Microstructural evolution in Nimonic 263 for high temperature power plant
conference contributionposted on 2014-07-25, 13:29 authored by Sean A. Smith, Geoff West, K. Chi, W. Gamble, Rachel ThomsonRachel Thomson
It is necessary to develop and implement new power plant due to both current energy and environmental demands. To enable these objectives to be met, the next generation of power plant must be more efficient. A common method of improving efficiency in plant is to increase the steam temperatures and pressures, which will necessitate the introduction of new materials. Nickel-based alloys lend themselves to high temperature and pressure applications due to their significant creep strength and the ability to operate at metal temperatures above 750°C. Steam header and pipework systems carry steam from the boilers to the turbines and are of particular interest in this research. Header and pipework systems experience high operating temperatures and pressures in the power plant, and it is therefore paramount that a suitable material is chosen and methodologies are put in place to predict their safe operating lifetimes Microstructural evolution in Nimonic 263, one candidate material for next generation plant, has been quantified using a variety of advanced analytical electron microscopy techniques, including field emission gun scanning electron microscopy (FEGSEM) and transmission electron microscopy (TEM). A focussed ion beam technique has also been used to produce site specific samples for examination in the TEM to assist in the identification of grain boundary precipitates. The changes occurring in the microstructure as a result of time and temperature of exposure have been quantified and the precipitates fully identified. The results are also compared to predictions from thermodynamic equilibrium calculations. It is shown that variation in exposure time and temperature can affect the microstructural development, and therefore the mechanical properties, of the Nimonic 263 alloy.
The authors would like to acknowledge the support of EPSRC through the Supergen 2 programme [grant numbers GR/S86334/01 and EP/F029748] and the following companies; Alstom Power Ltd., Corus, E.ON Engineering Ltd., Doosan Babcock, National Physical Laboratory, QinetiQ, Rolls- Royce plc, RWE npower, Sermatech Ltd. and Siemens Industrial Turbomachinery Ltd. for their valuable contributions to the project.
- Aeronautical, Automotive, Chemical and Materials Engineering
Published inAdvances in Materials Technology for Fossil Power Plants - Proceedings from the 6th International Conference
Pages110 - 126
CitationSMITH, S.A. ... et al, 2011. Microstructural evolution in Nimonic 263 for high temperature power plant. IN: Advances in Materials Technology for Fossil Power Plants - Proceedings from the 6th International Conference, 31st August-3rd September 2010, Santa Fe, New Mexico. Materials Park, Ohio: ASM International, pp. 110 - 126
Publisher© ASM International and Electric Power Research Institute
- AM (Accepted Manuscript)
NotesCopyright 2011 ASM International, www.asminternational.org. This article was published in Advances in Materials Technology for Fossil Power Plants - Proceedings from the 6th International Conference and is made available as an electronic reprint with the permission of ASM International. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplications of any material in this article for a fee or for commercial purposes, or modification of the content of this article is prohibited.