Sintering properties of V2O5, Ta2O 5 and Nb2O5 doped ThO2 powder under Ar-10% H2 atmosphere


Yayli A., KIRTAY S., OKTAY E., Van A., Aybers M., Çolak L.

Proceedings of the 8th Conference and Exhibition of the European Ceramic Society, İstanbul, Türkiye, 29 Haziran - 03 Temmuz 2003, ss.305-308, (Tam Metin Bildiri) identifier

  • Yayın Türü: Bildiri / Tam Metin Bildiri
  • Cilt numarası:
  • Basıldığı Şehir: İstanbul
  • Basıldığı Ülke: Türkiye
  • Sayfa Sayıları: ss.305-308
  • İstanbul Üniversitesi-Cerrahpaşa Adresli: Hayır

Özet

ThO2 powder was obtained by precipitating thorium oxalate from thorium nitrate solution using oxalic acid in the presence of ultrasound and then calcinating the precipitate. ThO2 and 0.25 mol% V 2O5, 0.25 mol% Ta2O5 and 0.25 mol% Nb2O5 separately mixed then pressed into cylindrical pellets. The green pellets were sintered at 1400 and 1700°C under Ar-10% H2 atmosphere. Sintered densities of pellets were determined and microstructural observations carried out. The results showed that Ta 2O5 and Nb2O5 doped ThO2 pellets had higher densities than V2O5 doped ThO 2 pellets after sintering at 1400 and 1700°C. Ta 2O5 and Nb2O5 doped ThO2 pellets reached a density of 97% TD after sintering at 1700°C. Microstructural observations showed that V2O5 doped thoria pellets after sintering at 1700°C had average grain size of 15 μm while it was 32 and 30 μm for the Nb2O5 and Ta 2O5 doped ThO2 pellets, respectively.