Reactive multilayer systems

Applications

Reactive nanometer multilayers: Customized heat sources for low-stress joining of metals and ceramics

Joining of a Si wafer with Marcor glass ceramics using reactive multilayer systems
© Fraunhofer IWS Dresden
Joining of a Si wafer with Marcor glass ceramics using reactive multilayer systems
Reactively joined material combinations
© Fraunhofer IWS Dresden
Reactively joined material combinations
Reactively joined hat profile made of carbon fiber reinforced polyetherimide
© Fraunhofer IWS Dresden
Reactively joined hat profile made of carbon fiber reinforced polyetherimide

Joining of metals and ceramics

The application of the reactive foil for joining processes has so far been demonstrated for soft soldering of the following material combinations: brass - brass, ceramic - silicon, invar - silicon, silicon - silicon, ceramic - stainless steel, aluminum - copper, aluminum - steel, steel - carbide. The necessary solders with melting temperatures in the range of 200 - 300 °C were applied either to the foil or to the components.

A significant further development of reactive joining technology has been achieved by doubling the amount of energy provided by the reactive foils. This means that solders with melting temperatures of up to just above 700 °C (e.g. Incusil ABA (Wesgo), AlSi10) can now also be used. The approach allows the joining of components that are subject to high temperature loads in case of application. In addition, the strength of the joints can also be improved with these solders.


Joining of polymers

Within a very short time, remarkable results have also been achieved in joining polymers (polymers, plastics) with reactive foils. Here, the energy provided by the foils is used to directly melt the surfaces of the polymers so that the polymer components are subsequently fused together. The fact that the amount of heat supplied by the foils can be precisely controlled by their nanolayer structure is particularly advantageous in this application. On the one hand, burning of the polymers can be avoided and on the other hand a defined liquid phase can be generated.


Outlook

The aim of future work is to also use solders with melting temperatures above 1000 °C. This would provide a very promising temperature range, especially for joining ceramics.