Thermal stability of yittrium-and-neodymium-doped alpha/beta-SiAlON ceramics

Kurama S., Herrmann M.

SILICATES INDUSTRIELS, cilt.69, sa.7-8, ss.241-248, 2004 (SCI-Expanded) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 69 Sayı: 7-8
  • Basım Tarihi: 2004
  • Dergi Adı: SILICATES INDUSTRIELS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED)
  • Sayfa Sayıları: ss.241-248
  • Anahtar Kelimeler: alpha-SiAlON, stability region, Rietveld analysis, thermal stability, SUBSOLIDUS PHASE-RELATIONSHIPS, SYSTEM SI,AL,Y/N,O
  • Anadolu Üniversitesi Adresli: Hayır

Özet

A series of samples of yttrium and neodymium containing alpha-SiAlON (Rx+vSi12-(m+n)Alm+nOnN16-n with R = Y, Nd) has been synthesised at different temperatures and isothermal sintering times. The Rietveld technique was used for the determination of the x value of the alpha-SiAlONs. This method offers the possibility to determine the boundaries of two phase field beta-SiAlON/alpha-SiAlON with a high accuracy. On the basis of these data, the stability regions of Y- and Nd-alpha-SiAlONs were established at different temperatures. At n-values less than 0.5 x-values as low as 0.24 +/- 0.02 for Y and 0.30 +/- 0.02 for Nd-alpha-SiAlON were observed. The m values at the boundary of the stability region are nearly independent on the temperature (1650 - 1900degreesC).