| Popis: |
Alumina based transparent ceramic bodies were prepared within this diploma thesis by the gel casting process followed by presintering to closed porosity stage with subsequent hot isostatic pressing. The problematic drying of large bodies was solved by means of careful temperature and relative humidity control and by osmotic drying. Almost perfectly dense ceramics were achieved thanks to colloidal processing of TM-DAR and TM-UF ceramic powders providing a final structure with grain size of 381 nm, resp. 302 nm. High real in-line transmission of 72,3 % was achieved at wavelength of 632,8 nm and thickness of 0,8 mm. Among mechanical properties high values of hardness HV10 = 22,5 GPa, fracture toughness KIC = 3,99 MPam0,5, Young’s modulus E = 400 GPa a bending strength o = 494 MPa were achieved. |
