Copper‐substituted bismuth vanadate (Bi2V0.9Cu0.1O5.35), known as BICUVOX, possesses high oxygen ion conductivities at low temperatures. The ionic conductivity of this material at 300°C (∼1 × 10−3 S/cm) is 50 to 100 times greater than any other solid electrolyte in this temperature range. In this paper we report the preparation of sinterable BICUVOX powders by solid‐state reaction and conventional ceramic powder processing techniques. Densification studies indicate that optimum densities (>95% theoretical) can be obtained after 10‐20 h sintering at 800°C. Ionic conductivity characteristics were evaluated with respect to temperature, sample density, and prolonged isothermal heating.

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Poly (L-lactic acid) (PLLA) and composite of PLLA with osteoconductiveβ-tricalcium phosphate fine powder (PLLA/TCP) compression moulded specimens were subjected toin vitrobiodegradation up one year. Samples were investigated in terms of physical-chemical evaluation after several periods of incubationin simulated body fluid solution. Reduction in PLLA molecular weights occurred during thermal processing of compounding of the polymer with TCP. 3-point bending measurements revealed some decay in the flexural strength and increase in stiffness after incorporation of the inorganic particles into the polymer. Those parameters remained nearly stable during the biodegradation period despite constant drop of polymer molecular weight. Thermal properties of both kinds of samples did not changed significantly, however degree of crystallinity of PLLA matrix was increasing slowly in pure PLLA samples. Despite no mass loss,extent of surface deteriorationincreased steady during the incubation. Current study is intended to develop material for implants, mainly fusion cages targeted for spinal applications.

Synthesis, Densification, and Conductivity Characteristics of BICU-VOX Oxygen-Ion-Conducting Ceramics.-Phase pure sinterable powders of Cu-substituted bismuth vanadate, Bi 2 V 0.9 Cu 0.1 O 5.35 (BICU-VOX.10), are prepared by solid state reaction and calcining at 800 • C and the densification characteristics are studied as a function of sintering time and temperature. Ceramic monoliths of ¿95% of theoretical density are obtained by sintering at 800 • C. The densified ceramics with an equiaxed microstructure of ¡10 µm grain size exhibit an ionic conductivity at 300 • C of ≈1·10 −3 S/cm, i.e. 50 to 100 times greater than any other solid electrolyte in this temp. range. No significant changes in conductivity are observed after isothermal heating at 450 and 500 • C for ≈250 hours. -(SIMNER, S. P.; SUAREZ-SANDOVAL, D.; MACKENZIE, J. D.; DUNN, B.; J.