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Due to their very specific set of material properties, silicon nitride and silicon carbide have gained a lot of interest in the
last 20 years. Moreover, many new approaches in technical equipment and processes were enabled with corresponding
research and production activities.
Also large efforts were made at FCT during the last years, to get able to supply even very large and complex shaped
components made of sintered silicon carbide (SSiC) and of gas pressure sintered silicon nitride (GPSN) ceramics. This
approach has opened new applications and markets for such ceramic materials. On the other side, designers and
engineers are now allowed to think much more complex in designing of ceramic components. In this paper, a new rapid
prototyping routine for very complex components as well as the corresponding materials will be presented. Components
for optical equipment in innovative avionic and space applications, and more conventional technologies are described.
Not only their unique key intrinsic properties, like high Youngs Modulus, very low CTE, very high strength and fracture
toughness for a ceramic but also newly developed and adopted shaping, sintering and machining technologies in both
green and sintered state have let to highly valued products. This enabled FCT to offer Carl Zeiss Optronics using silicon
nitride for a newly designed, very complex housing structure of an avionic pod camera. Due to a very low CTE, high
stiffness and less weight, an improved performance was reached.
Also Thales Alenia Space is engaged since some years in activities to develop and qualify Silicon nitride ceramics for
space projects. Extremely stiff, very lightweight and large truss space structures with a very low CTE, high rigidity and
no outgasing for satellites can now be realized. Deep tests sequence has been performed to qualify truss beams and end
fittings made in the same material.
Also advanced dynamic testing equipment for avionic turbine blades requires new approaches. In cooperation with
TIRA a series of shaker heads were developed which can operate at much higher frequencies and so reduce fatigue
testing time and costs. Last but not least, highly precise and thin walled disc structures with diameters up to 380 mm are
produced for wafer handling and testing equipment.
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