High-temperature joining by soldering or adhesive bonding

Topic

© Fraunhofer IKTS
Active solder joint between ceramic foam heating element and a contact element.

Ceramic components are often exposed to extreme thermal loads. Due to their construction or function, these components often consist of different ceramics or metal components. In particular, the use of multi-material systems in high-temperature applications requires new, thermally stable joints that are individually adapted to the materials and application parameters. In addition, there are applications where the ceramic composites are exposed to abrasive, chemical or mechanical loads. With these tasks in mind, we develop individual solutions for joining ceramic composites. For this purpose, we use or modify commercial solders and adhesives. For applications where commercial solutions do not meet the requirements, we develop new brazing materials and joining technologies including diffusion joining concepts.

Services offered

 

  • Concept development for the joining of components and systems
  • Joining of ceramic and metallic materials by active soldering, bonding and diffusion joining
  • Active soldering using commercially available solders under vacuum or inert gas
  • Solder development for ceramic/ceramic or ceramic/metal material composites for high-temperature applications up to 1500 °C
  • Metallization of ceramic surfaces by deposit soldering
  • Mechanical testing of ceramic/ceramic or ceramic/metal composites under thermal load
  • Characterization of material composites and solders
  • Defect identification for joining processes and composites

 

Technical equipment

 

  • High-temperature tungsten furnace for applications up to 2200 °C, in variable atmospheres (up to 10-5 mbar vacuum, Ar, N2, H2 and gas mixtures)
  • Mechanical materials testing for composite characterization, especially bending, tensile, compression and shear tests and high-temperature strength

 

Application examples / references

 

  • Electrical contacting of ceramic heating conductors
  • High-temperature resistant brazed joints for shaft and rotor in a turbine
  • Bonded ceramic-metal composites