Příprava tenkostěnných trubic z ZrO2 a CeO2 termoplastickým vytlačováním

Fabrication of zirconia- and ceria-based thin-wall tubes by thermoplastic extrusion

článek v časopise - ostatní, Jost

en

Thin-wall tubes made of zirconia stabilized by 8 mol% of yttria and of ceria doped by 10 mol% of gadolinia were prepared by thermoplastic extrusion. The rheological behaviour of the ceramic mixtures prepared and the effect of rheological properties on the deformation of tubes were studied. After sintering, the diameter of tubes was 10.5 mm and their wall thickness ranged from 270 to 420 mm. The deformation and shape irregularity of sintered tubes were determined. The tubes, which were sintered at a temperature of 1500 degC, had a relative density of more than 98% t.d. Flexural strength and fracture toughness of sintered ceramics were determined on test bars prepared by injection moulding from thermoplastic mixtures identical to those used for extrusion. The fracture toughness established was 1.7 MPa m0.5 for yttria-stabilized zirconia, and 1.1 MPa m0.5 for gadolinia-doped ceria.

Tenkostěnné trubice z oxidu zirkoničitého stabilizovaného 8 mol% Y2O3 a z oxidu ceričitého dopovaného 10 mol% Gd2O3 byly připraveny termoplastickým vytlačováním. Byl studován vliv reologických vlastností připravených keramických směsí na deformaci trubic. Průměr slinutých trubic byl 10,5 mm a jejich tloušťka stěny byla od 270 nm do 420 nm. Byly zjišťovány deformace a nepravidelnosti tvaru slinutých trubic. Trubice slinované při 1500 degC měly relativní hustotu větší než 98%. Ohybová pevnost a lomová houževnatost slinutých keramik byla zjišťována na trámcích připravených injekčním vstřikováním termoplastických směsí identických se směsmi pro vytlačování. Lomová houževnatost byla 1,7 MPa m0,5 pro ZrO2 a 1,1 MPa m0,5 pro CeO2.

Thin-wall tubes made of zirconia stabilized by 8 mol% of yttria and of ceria doped by 10 mol% of gadolinia were prepared by thermoplastic extrusion. The rheological behaviour of the ceramic mixtures prepared and the effect of rheological properties on the deformation of tubes were studied. After sintering, the diameter of tubes was 10.5 mm and their wall thickness ranged from 270 to 420 mm. The deformation and shape irregularity of sintered tubes were determined. The tubes, which were sintered at a temperature of 1500 degC, had a relative density of more than 98% t.d. Flexural strength and fracture toughness of sintered ceramics were determined on test bars prepared by injection moulding from thermoplastic mixtures identical to those used for extrusion. The fracture toughness established was 1.7 MPa m0.5 for yttria-stabilized zirconia, and 1.1 MPa m0.5 for gadolinia-doped ceria.

extrusion, suspensions, ZrO2, CeO2, electrolyte

2004

01.01.2004

Elsevier Science

0955-2219

Journal of the European Ceramic Society

24

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