The focus of this work is the theoretical and experimentell descreption of so-called Reactive Multilayer Systems (RMS). The RMS consist of at least two mostly metallic materials, which can exothermic response with each other. Using magnetron sputter deposition (MSD) several hundred to thousands alternating layers are produced. The periodic thickness varies between 10-150 nm and the total thickness between 10-100 µ m . The exotermic reaction is effected by an activation energy, e.g. with an electric spark. In this case a phase transition of the RMS materials, which are in a metastable equilibrium, will take place. This released energy in the shape of heat, which actvates the reaction in the neighboring areas. It forms a self-sustaining thermal wave through the RMS foil. In this case the amount of energy is present, that a solder on the RMS or the joining samples or even the material itself can be melted. Therefore the RMS can be used as a heat source for joining two components. The major advantage of this technology is the very low heat input in the bonding components, due to the milliseconds of the reaction. Thus the components are heated only superfical and there is no structural damage. Thus a very low-stress joining is possible.
Furthermore is guaranteed, because of the metallic materials, a very high electrical and thermal conductivity. For the theoretical characterization of the physical and chemical processes within the RMS FEM-Simulations of the absolut temperature and the propagation velocity are preformed. In order to calculate the tmeperature ditribution in the components a new method will presented. It is thus possible to calculate the temperature penetration of the components to determine potential thermal barrier layer-thickness and the meltig time. Thus parameters for the specific joint problem such as period thickness, etc. of the RMS are derived. Modelling the heat transport after joining with RMS it is possible to derive a corralation between the thermal conductivity and shear strength. To quantify the theoretical results and to require certain parameters for the calculations experiments were preformed. The RMS will be investigated experimentally in terms of their enthalpy H , propagation velocity v , nascent temperature, melting time t schmelz , interdiffusion zone w , phase transition and its use as inovative heat source for joining components. The experimental results are compared with the theortical and complet this work.
| Identifer | oai:union.ndltd.org:DRESDEN/oai:qucosa.de:bsz:14-qucosa-198818 |
| Date | 23 May 2016 |
| Creators | Rühl, Maximilian |
| Contributors | Technische Universität Dresden, Fakultät Maschinenwesen, Dr. rer. mat. Stefan Braun, Prof. Dr.-Ing. Dr. h.c. Eckhardt Beyer, Prof. Dr.-Ing. Andrés-Fabián Lasagni |
| Publisher | Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden |
| Source Sets | Hochschulschriftenserver (HSSS) der SLUB Dresden |
| Language | deu |
| Detected Language | English |
| Type | doc-type:doctoralThesis |
| Format | application/pdf |
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