REVIEW OF SCIENTIFIC INSTRUMENTS
VOLUME 73, NUMBER 2
FEBRUARY 2002
A new experimental setup for the time resolved x-ray diffraction study of self-propagating high-temperature synthesis D. Vrela) LIMHP, UPR 1311 CNRS, 99 Avenue J.-B. Cle´ment, F-93430 Villetaneuse, France and GFA, GDR 2391 CNRS, J.-C. Niepce, LRRS, BP 47870, F-21078 Dijon Cedex, France
N. Girodon-Boulandet LIMHP, UPR 1311 CNRS, 99 Avenue J.-B. Cle´ment, F-93430 Villetaneuse, France
S. Paris, J. F. Mazue´, and E. Couqueberg LRRS, UMR 5613 CNRS/Universite´ de Bourgogne, Boıˆte Postale 47870, F-21078 Dijon Cedex, France
M. Gailhanou LURE, UMR 130 CNRS/CEA/MENRT, Bat 209 D, Universite´ Paris Sud, F-91405 Orsay Cedex, France
D. Thiaudie`re LURE, UMR 130 CNRS/CEA/MENRT, Bat 209 D, Universite´ Paris Sud, F-91405 Orsay Cedex, France and CRMHT, UPR 4212 CNRS, 45071 Orle´ans cedex 2, France
E. Gaffetb) UMR 5060 CNRS, Nanomaterials Research Group, UTBM/Sevenans, F-90010 Belfort Cedex, France and GFA, GDR 2391 CNRS, J.-C. Niepce, LRRS, Boıˆte Postale 47870, F-21078 Dijon Cedex, France
F. Bernardc) LRRS, UMR 5613 CNRS/Universite´ de Bourgogne, Boıˆte Postale 47870, F-21078 Dijon Cedex, France and GFA, GDR 2391 CNRS, J.-C. Niepce, LRRS, Boıˆte Postale 47870, F-21078 Dijon Cedex, France
~Received 23 July 2001; accepted for publication 27 November 2001! A new experimental setup for time resolved x-ray diffraction is described. Designed for the LURE H10 beamline and its 4 ~12! circles goniometer, it allows simultaneous recordings of x-ray patterns with a rate of 30 patterns per second, a maximum 2u range of 120°, infrared thermography at the same rate, and thermocouples readings at a frequency of up to 33104 Hz. Preliminary results obtained using this setup are presented, showing how it is possible to analyze a solid–solid or solid-liquid reaction. As an example, an in situ study of phase transformation and temperature evolution during the self-sustaining synthesis of an FeAl intermetallic compound starting from a mechanically activated mixture is investigated. The versatility of the setup was proved and could even be enhanced by the design of new sample holders, thus expanding its area of use at low cost. © 2002 American Institute of Physics. @DOI: 10.1063/1.1435848#
I. INTRODUCTION
rare, mainly because the control of the reaction seems difficult, since most of the features of the reaction are governed by the initial conditions. Moreover, the process itself, consisting of a wave reaching very high temperatures in a very short time ~often more than 2000 K/s! and propagating at important speeds ~up to 100 mm/s!, makes the whole process difficult to apprehend, as the chemical kinetics are intimately mixed with a strong variation of all physical properties. In order to control SHS reactions, a better understanding of the initial conditions is usually sought, since the initial conditions are the easiest, if not the only parameters we can use to control the reaction. Many different characterizations have been used for this purpose, as well as to determine the properties of the products. However, this approach appears to be insufficient, and the characterization of the chemical and physical paths during the reaction through in situ measurements has become necessary. Aside from thermocouples and thermography, which can provide a reliable measurement of the thermal history of the reacting sample, tools providing information about the chemical path such as time-resolved
Self-propagating high-temperature synthesis ~SHS!, also known as combustion synthesis, is an evolution of the socalled thermite process, which is still used nowadays to weld railway tracks: the reaction used in this case, Fe2 O3 12Al →Al2 O3 12Fe, is highly exothermic and produces the liquid iron required for this welding, without requiring the high energy amount of a traditional electric welder. It is therefore perfectly adapted for railway operations, which are often performed in deserted areas. Once ignited by a local energy input, the reaction propagates in a wave-like fashion until the completion of the reaction, and the temperature can reach the level of a few thousand kelvin. Since its rediscovery in the mid 1960s by Russian scientists,1–3 hundreds of materials have been synthesized by this process. However, its practical use in industry is still a!
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© 2002 American Institute of Physics
