FP6 priority
1.1.3   Nanotechnologies and Nanosciences, Knowledge-based Multifunctional Materials and New Production Processes and Devices
Title of the proposal

Functionally graded materials

Slovak Academy of Sciences, Institute of Materials and Machine Mechanics
Racianska 75, 831 02 Bratislava, Slovak Republic
Dr. Stefan KAVECKY
+421 2 49268281

Research subject for a potential FP6 project

Functionally graded materials (FGMs) are materials containing at least two phases with volume fractions continuously varying along particular direction, displaying thus a property gradient evolution with regard to this direction. Therefore they are ideal for smooth reduction of thermomechanical stresses in joints between dissimilar materials (metals-ceramics or composites) that often suffer from spontaneous microcracking or interfacial debonding due to CTE mismatch. The proposed research is directed towards preparation of advanced FGM by one of the following four methods respecting the requirements of particular system:
1. plasma spraying of powders with changing mixture ratio along the thickness of coating, (e.g.: W-Cu, Cu-Al2O3, Cu-SiC, Al-SiC, Al-AlNi Ni-Al2O3, ZrO2-CoCrAlY , etc).
2. plasma-assisted reactive PVD with varying gas composition during coating (e.g. Al/AlN, Ti/Ti-Ti2N/Ti2N-TiN/TiN)
3. CVD of thin coatings with gradiently changing composition (e.g. C/SiC/Si3N4, SiC/Si3N4)
4. multiple dipping a substrate into slurries of varying composition (e.g. ZrO2-Y2O3/stainless steel)

Recent international cooperation of the research team

Austrian Research Centre, Seibersdorf, Austria; Frauenhoffer Institute for Applied Material Research, Dresden, Germany; Institute of Electronic Materials Technolgy, Warsaw, Poland

Proposerīs relevant publications related to the research subject

SAHU,S., KAVECKY, S., ILLESOVA,L. MADEJOVA,J. BARTOTI,I., SZEPVOLGYI,J.: Formationof BN Thin Films on b- Si3N4 Whiskers and a-SiC Platelets by Dip coating. J.Europ. Cer. Soc. 18, 1998, 1037-1043.
PALKA,J., IFNER,I., BREZOVSKY,M.,SEBO,P.: Plazmovy nastrek biokompatibilnych povlakov. Kovove mat. 30, 1992, 404-411.
KAVECKY, S., JANEKOVA,B., MADEJOVA,J., SAJGALIK,P.: Silikon Carbide Powder Synthesis by CVD from Silane/Acetylene reaction System. J. Europ. Cer.Soc. 20, 2000,1939-46.