Nitridation behaviour of ZrO2 added silicon powder with different ZrO2 particle sizes

Abstract

Effect of zirconia particle size on the nitridation behavior of silicon powder was studied in order to assess the influence of the zirconia particle size on the nitridation of silicon powder. Thermo-gravimetric analysis revealed that for samples held at higher temperatures the addition of zirconia powder resulted in a reduction of the temperature for the onset of nitridation of the silicon powder, and the degree of silicon to silicon nitride conversion at a given temperature was higher for samples nitrided with finer particle size of zirconia. For lower temperature, the degree of nitridation was studied as a function of holding time and samples with finer additions showed a much higher initial nitridation rate than those with coarser additions.

Fabrication of Dense β-SiAlON Ceramics with ZrO2 Additions Via a Rapid Reaction-Bonding and Postsintering Route

“…On the other hand, in the case of the SiAlON powder with ZrO 2 additions, the starting temperature of the main weight gain step occurring around 13001C was clearly lower than those for the other powders. 19,20 (2) Reaction Bonding and Postsintering Figure 3 shows the photographic images of the reaction-bonded SiAlON samples with and without ZrO 2 as a function of differ- Fig. 17 Figure 2 shows the normalized degree of nitridation, calculated from the TG analysis results, for mixed powders corresponding to the SiAlON composition of Z 5 1 with and without ZrO 2 that were heated and then held at 14001C under flowing nitrogen conditions.…”

“…This nitridation-enhancing mechanisms has been reported by the authors in detail. 19,20 (2) Reaction Bonding and Postsintering Figure 3 shows the photographic images of the reaction-bonded SiAlON samples with and without ZrO 2 as a function of differ- Fig. 1.…”

Equiaxed β–Si3N4 ceramics prepared by rapid reaction‐bonding and post‐sintering using TiO2–Y2O3–Al2O3 additives

“…The sintered reaction-bonded Si 3 N 4 has been considered as a more attractive alternative, due to the low cost of Si powders and low sintering shrinkage. [7][8][9] Results showed that all of the oxides exhibited nitridation enhancing effect. To overcome this problem, many researchers have reported the catalytic nitridation of Si.…”

“…1 The fabricating cost of Si 3 N 4 ceramics is the main barrier in sintering of Si 3 N 4 powder because of the high cost of raw materials as well as post-machining process. [5][6][7][8][9] Hyuga et al studied the effect of oxides additives including ZrO 2 plus 16 kinds of rare earth oxides on nitridation of Si powders. [2][3][4] However, the application of sintered reaction-bonded Si 3 N 4 ceramics is limited by the long processing time such as slow nitridation of Si powders.…”

“…[5][6][7][8][9] Hyuga et al studied the effect of oxides additives including ZrO 2 plus 16 kinds of rare earth oxides on nitridation of Si powders. [7][8][9] Results showed that all of the oxides exhibited nitridation enhancing effect. In particular, Eu 2 O 3 and ZrO 2 additions showed a larger enhancing effect of nitridation than the other oxides.…”