Fraunhofer Institute for Ceramic Technologies and Systems IKTS
Fraunhofer Institute for Ceramic Technologies and Systems IKTS

Cold sintering processing of ceramics

Topic

Cold sintering processing (CSP) is an emerging method of ceramic material densification under applied pressure and using reactive additives. It offers substantially reduced sintering temperatures (<400°C) and shorter processing time as compared to conventional furnace-based methods. Fraunhofer IKTS investigates influence of sintering additives and processing parameters on the resulting material properties and microstructure to realize novel material combinations with improved performance.

 

Key features of the technology
 

  • Sintering of a broad range of materials under high pressure at temperatures below 400°C
  • Co-sintering of ceramics and other materials with very different conventional sintering temperatures
  • Avoiding undesired thermal decomposition reactions during sintering
  • Sintering of material composites with different thermal stability ranges (e.g. ceramic/polymer)

 

Demonstrated materials and components
 

Electrolyte tapes for Na solid-state batteries

  • Production of thin (thickness <260 µm), translucent NaSICON tapes
  • Ionic conductivity of 0.27 mS/cm after CSP at 375°C
© Fraunhofer IKTS

All-ceramic Na solid-state battery

  • Co-sintering of composite cathode (NVP/NaSICON) and electrolyte
  • Cycling possible without liquid or polymer electrolytes

All-solid-state composite cathode for Li solid-state batteries

  • CSP of the LATP/LFP cathode at 200°C
  • Tape-based starting components
  • Direct use for cell construction after sintering
  • No liquid/polymer electrolytes in cathode

Li2O-Al2O3-SiO2 (LAS) glass ceramics (pellets)

  • CSP at temperatures from 280°C to 320°C
  • Low thermal expansion coefficient and high relative density (> 95 % of bulk material values)

CaRuO3 (pellets)

  • CSP at 380°C
  • Relative densities > 85 %
  • Potential applications as inert anode in molten-salt electrolysis

 

Services offered

  • Tailoring cold sintering parameters to achieve optimal performance of the customer-specific materials and components
  • Determining microstructure and properties (e.g. ionic and electronic conductivity) of the materials in relation to their cold sintering parameters
  • Partnership in collaborative research projects, performing feasibility studies, preparing prototypes and demonstrators, providing verification samples

 

Publications
 

  • M. Vinnichenko, K. Waetzig, A. Aurich, C. Baumgaertner, M. Herrmann, C.W. Ho, M. Kusnezoff, C.W. Lee Li-Ion Conductive Li1.3Al0.3Ti1.7(PO4)3 (LATP) Solid Electrolyte Prepared by Cold Sintering Process with Various Sintering Additives. Nanomaterials 12, 3178 (2022). (Link)
  • E. Dashjav, M. Bhardwaj, M.-T. Gerhards, Q. Ma, K. Wätzig, C. Baumgärtner, D. Wagner, A. Lowack, M. Kusnezoff, F. Tietz. Phase Evolution of NaSICON Materials during Temperature-Dependent Conventional and Cold Sintering. ACS Appl. Energ. Mater. Published on-line July 29, 2025. (Link)

 

Further information