FUORCLAM

Fundamental Understanding of Oxide Refractory Ceramics and
Laser Additive Manufacturing

Selective laser sintering (SLS) and selective laser melting (SLM) is already getting a mature technology in metals and polymer processing. In contrary, in high tech ceramics based materials there is no existing SLS process available to consolidate, either by solid state or by liquid state sintering processes, ceramic powders to dense structures with convenient materials properties. The consortium will study the laser interaction of oxide based starting materials and the effect of composite granule composition and morphology on the absorption behaviour of pulsed lasers. The new SLM process will offer the opportunity to create ceramic gradient structures with defined porosities and possible applications as implant materials or as machine parts, where the formation of intimate contacts between metal and ceramic parts is still an issue.

Scope of Research Activities

Flame spray synthesis of doped nano-alumina (n-Al2O3)
Manufacturing of alumina granules (Al2O3) by spray drying
Design of Al2O3-n-Al2O3 granule structures
Laser processing (SLM) of alumina powders
Creation of gradient and dense structures
Characterization of alumina powders and produced samples

In situ solidification experiments

Key Technical Problems to Solve

Laser light / ceramic absorption behaviour
Powder flowability and bed packing density
Process design for one step sintering approach
Thermal stresses leading to cracks during processing

Demonstrators

5 mm cube with high density
Parts with locally graded densities
Dental implants

Leading Principal Investigator

Prof. Dr. Konrad Wegener
Institute of Machine Tools and Manufacturing, ETH Zürich

Project Consortium

Prof. Dr. Thomas Graule, Laboratory for High Performance Ceramics, Empa
Prof. Dr. Helena Van Swygenhoven, Photons for Engineering and Manufacturing Group, PSI