Heat and Mass Transfer in Reactive Multilayer Systems (RMS)
M. Rühl1 G. Dietrich2 E. Pflug1 S. Braun2 A. Leson2
1TU Dresden, Laser and Surface Technology, Dresden, Germany
2IWS Dresden, Fraunhofer Institute for Material and Beam Technology, Dresden, Germany
Established joining techniques like welding, soldering or brazing typically are characterized by a large amount of heat load of the components. Especially in the case of heat sensitive structures like MEMS this often results in stress induced deformation and degradation or even damaging of the parts. A back door of this problem are Reactive Multilayer Systems (RMS). These foils consist of several hundred to thousand of alternating periodical reactive materials, e.g. Al-Ni. After a suitable ignition these layers can react exothermically, atomic diffusion in z-direction (figure1) with each other. Thus a termal wave in x-direction is generated and self propagation front is formed.
A two dimensional model was generated using COMSOL Multiphysics 3.5a atomic diffusion and heat equation are coupled.