1. Development of Ceramic Materials with Extreme Mechanical Properties
EUROMAT 2005 Conference PRAGUE
Development of Ceramic Materials with Extreme Mechanical Properties
Dr. László A. Gömze
H-3515 Miskolc-Egyetemváros, Hungary
Tel

2. ABSTRACT Mechanical properties of ceramics
Factures influence on mechanical properties of ceramics
Microstructure and Morphology of technical ceramics
Distribution of pressure stresses in ceramic powders during their compacting
Ceramic items with extreme mechanical properties
Dr. GÖMZE A. László,
Department of Ceramics and Silicate Engineering, University of Miskolc

3. MECHANICAL PROPERTIES OF CERAMICS
STRENGTH
Pressure strength (Rp)
Shearing strength (Rs)
Bending strengt (Rb)
Tensile strength (Rh)
HARDNESS
Micro-hardness (HVmi)
Macro-hardness (HVma)
RHEOLOGICAL PROPERTIES (i, Ei, 0, )
Dr. GÖMZE A. László,
Department of Ceramics and Silicate Engineering, University of Miskolc

4. FACTURES, INFLUENCE ON MECHANICAL PROPERTIES OF TECHNICAL CERAMICS
Chemical composition (Cc)
Shapes (Sg) and grain sizes (Gs) of used ceramic powders
Distribution of grain shapes and sizes in forming dies (Dg)
Distribution of pressure stresses in ceramic bidies during their compacting (Dp)
Temperature (Ts) and atmosphere (Sa) of sintering

5. PRESSURE STRENGTH AND MICRO HARDNESS AS FUNCTION OF INFLUENCE FACTURES
Rp = f(Cc, Dg, Dp, Gs, Sa, Sg, Ts);
HVmi = f(Cc, Dg, Dp, Gs, Sa, Sg, Ts)

6. THE TIPICAL SHAPES AND DISTRIBUTION OF ATOMIZER POWDERS IN FORMING DIES

7. INFLUENCE OF POWDER GRAIN SIZES AND THEIR DISTRIBUTION ON MICROSTRUCTURE AND MORPHOLOGY OF FIRED CERAMIC ITEMS

8. DISTRIBUTION OF PRESSURE STRESSES IN CERAMIC POWDERS DURING THEIR COMPACTING WITH UNIAXIAL TECHNOLOGY
[MPa]

9. PRESSURE DISTRIBUTION IN FORMING DIES WITH TRUNCATED CONE SHAPES
[MPa]

10. PRESSURE DISTRIBUTION IN FORMING DIES WITH RECTANGULAR PRISMATIC SHAPES
[MPa]

11. PRESSURE DISTRIBUTION IN FORMING DIES WITH REGULAR HEXAGONAL PRISMATIC SHAPES
[MPa]

12. PRESSURE DISTRIBUTION IN FORMING DIES WITH TRUNCATED PYRAMID SHAPES
[MPa]

13. PRESSURE DISTRIBUTION IN FORMING DIES WITH SPHERICAL SEGMENT OF SHAPES
[MPa]

14. PRESSURE DISTRIBUTION IN FORMING DIES WITH QUARTERED TORUS SHAPES
[MPa]

15. THE REQUIRED „MINIMUM” VALUE OF DEVELOPED PRESSURE STRESS IN CERAMIC BODIES DURING THEIR FORMING IN DIES WITH CYLINDRICAL SHAPES
[MPa]

16. THE REQUIRED „MINIMUM” VALUE OF DEVELOPED PRESSURE STRESS IN CERAMIC BODIES DURING THEIR FORMING IN DIES WITH TRUNCATED CONE SHAPES
[MPa]

17. THE REQUIRED „MINIMUM” VALUE OF DEVELOPED PRESSURE STRESS IN CERAMIC BODIES DURING THEIR FORMING IN DIES WITH SPHERICAL SEGMENTS OF SHAPES
[MPa]

18. THE SYMBOLS USED IN MATHEMATICAL EQUATIONS
a, A, b, B, r, r0, R, R0, d, D, , ,  and  - are geometrical parameters
f, fb –friction ratios
p – the outside pressure, developed by pressing punchers
L – distance from the contact surface of pressing punchers to the examined place in ceramic powders

19. UNDER PRESSED POWDERS WELL PRESSED POWDERS
INFLUENCE OF THE PRESSURE STRESSES ON THE MICROSTRUCTURE AND MORPHOLOGY OF FIRED ALUMINA CERAMIC ITEMS
UNDER PRESSED POWDERS WELL PRESSED POWDERS

20. OPTIMUM PRESSED POWDERS
INFLUENCE OF THE PRESSURE STRESSES ON THE MICROSTRUCTURE AND MORPHOLOGY OF FIRED ALUMINA CERAMIC ITEMS
WELL PRESSED POWDERS WITH OPTIMUM GRAIN SIZE DISTRIBUTION IN FORMING DIE
OPTIMUM PRESSED POWDERS

21. CONCLUSION
THE FAILURES AND MISTAKES MADE DURING COMPACTING OF CERAMIC ITEMS CAN NOT BE CORRECTED WITH SINTERING AND OTHER TECHNOLOGICAL OPERATIONS
THE VALUES AND DISTRIBUTION OF PRESSURE STRESSES ARE THE MAIN FACTURES WHICH INFLUENCE ON PRESSURE STRENGTHES OF TECHNICAL CERAMIC ITEMS MADE FROM AL2O3 POWDERS
WE ARE THE FIRST WHO COULD DESCRIBE THE MATEMATICAL EQUATIONS OF PRESSURE DISTRIBUTION IN CERAMIC BODIES DURING THEIR COMPACTING IN DIES OF DIFFERENT GEOMETRICAL SHAPES

22. THANK YOU FOR YOUR ATTENTION