title: Ru/Al Multilayers Integrate Maximum Energy Density and Ductility for Reactive Materials.
abstract: Established and already commercialized energetic materials, such as those based on Ni/Al for joining, lack the adequate combination of high energy density and ductile reaction products. To join components, this combination is required for mechanically reliable bonds. In addition to the improvement of existing technologies, expansion into new fields of application can also be anticipated which triggers the search for improved materials. Here, we present a comprehensive characterization of the key parameters that enables us to classify the Ru/Al system as new reactive material among other energetic systems. We finally found that Ru/Al exhibits the unusual integration of high energy density and ductility. For example, we measured reaction front velocities up to 10.9 (± 0.33) ms(-1) and peak reaction temperatures of about 2000 °C indicating the elevated energy density. To our knowledge, such high temperatures have never been reported in experiments for metallic multilayers. In situ experiments show the synthesis of a single-phase B2-RuAl microstructure ensuring improved ductility. Molecular dynamics simulations corroborate the transformation behavior to RuAl. This study fundamentally characterizes a Ru/Al system and demonstrates its enhanced properties fulfilling the identification requirements of a novel nanoscaled energetic material.
authors.affiliation: Functional Materials, Department of Materials Science, Saarland University, 66123 Saarbrücken, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Woll
authors.affiliation: Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland.
authors.forename: A
authors.initials: A
authors.lastname: Bergamaschi
authors.affiliation: Materials Physics, Department of Physics, University of Helsinki, 00014 Helsinki, Finland.
authors.forename: K
authors.initials: K
authors.lastname: Avchachov
authors.affiliation: Materials Physics, Department of Physics, University of Helsinki, 00014 Helsinki, Finland.
authors.forename: F
authors.initials: F
authors.lastname: Djurabekova
authors.affiliation: Experimental Physics, Saarland University, 66123 Saarbrücken, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Gier
authors.affiliation: Functional Materials, Department of Materials Science, Saarland University, 66123 Saarbrücken, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Pauly
authors.affiliation: Functional Materials, Department of Materials Science, Saarland University, 66123 Saarbrücken, Germany.
authors.forename: P
authors.initials: P
authors.lastname: Leibenguth
authors.affiliation: Experimental Physics, Saarland University, 66123 Saarbrücken, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Wagner
authors.affiliation: Materials Physics, Department of Physics, University of Helsinki, 00014 Helsinki, Finland.
authors.forename: K
authors.initials: K
authors.lastname: Nordlund
authors.affiliation: Functional Materials, Department of Materials Science, Saarland University, 66123 Saarbrücken, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Mücklich
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