174 Prakt. Met. Sonderband 46 (2014) 
5. SUMMARY VERB! 
The strength distribution of different glass-ceramic composite systems was determined VON § 
using a biaxial strength testing method (the Ball-on-three-balls test). Bulk substrates with ANWE 
different microstructure were compared with multilayer architectures combining two 
different materials. An increase in strength was measured in the multilayer composites W. Harre 
related to the compressive stresses in the surface layers, generated during sintering due eo 
to the different thermal expansion coefficients of the combined microstructures. The Institut fi 
residual stress in the surface layers measured with Raman spectroscopy was in FCT Inc 
agreement with the increase in strength with respect to the bulk samples. 
ACKNOWLEDGEMENTS 
ABSTR 
Financial support by the Austrian Federal Government (in particular from the Bundesministerium fiir Verkehr, 
Innovation und Technologie and the Bundesministerium fur Wirtschaft und Arbeit) and the Styrian Provincial Aufgrund 
Government, represented by Osterreichische Forschungsforderungsgesellschaft mbH and by Steirische SisNg in 
Wirtschaftsforderungsgeselischaft mbH, within the research activities of the K2 Competence Centre on CL 
“Integrated Research in Materials, Processing and Product Engineering’, operated by the Materials Center Bei einig‘ 
Leoben Forschung GmbH in the framework of the Austrian COMET Competence Centre Programme, is Versagen 
gratefully acknowledged. startet vo 
oft durcl 
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