Research Profile - Department of Materials Science and Metallurgy ...

Howard Stone
Assistant Director of Research
MA University of Cambridge
PhD University of Cambridge
+44 (0) 1223 334320
hjs1002@cam.ac.uk
www.msm.cam.ac.uk/utc/
High-Temperature Materials
The ongoing drive for improved fuel efficiency and reduced
emissions from gas-turbine aeroengines continues to demand
materials capable of tolerating ever higher service temperatures.
The majority of these applications are served by nickel-base
superalloys, but new materials are now also being considered as
potential successors to these alloys in many applications.
Nickel-base superalloys
The outstanding combination of properties of nickel-base
superalloys has led to their widespread use in hot-section
aeroengine components. After many years of research, continued
improvements are still being achieved in the conditions that
may be tolerated by these materials in service. My research is to
develop our understanding of the relationship between the alloy
composition, microstructure and properties, and how these are
influenced by the processing and service conditions, in order to
further improve the properties of these alloys and extend their
lives in service.
Novel high-temperature materials
We are investigating novel materials that may provide viable
alternatives to nickel-base superalloys in high-temperature
applications such as aeroengines. While no material improves
on conventional nickel-base superalloys in all regards, an
understanding of the conditions that must be tolerated by
individual components is leading to the identification and
development of novel materials that may enable higher
temperatures, stresses, longer lives or lighter components to be
achieved.
In-situ characterization of phase transformations
Modern diffraction-based techniques using neutron and
synchrotron sources such as the ISIS and ILL neutron sources
and the European Synchrotron Radiation Facility offer powerful
methods for the in-situ characterization of crystal structures in
metals and alloys. With these methods, phase transformations
are being studied on timescales of milliseconds and with very
high resolution, providing unique insights into these processes.
HJ Stone, TM Holden & RC Reed, “On the generation of microstrains
during the plastic deformation of Waspaloy” Acta Mater. 47, 4435–4448
(1999).
D Dye, HJ Stone & RC Reed, “Intergranular and interphase microstresses”
Curr. Opin. Solid State Mater. Sci. 5, 31–37 (2001).
HJ Stone, MG Tucker, FM Méducin, MT Dove, SAT Redfern, Y Le Godec
& WG Marshall, “Temperature measurement in a Paris-Edinburgh cell by
neutron resonance spectroscopy” J. Appl. Phys. 98, 064905 (2005).
Reciprocal lattice point of a fundamental reflection from a fourthgeneration
single-crystal nickel-base superalloy obtained by
synchrotron X-ray diffraction
36 Research Profile