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Journal of Materials Science

, Volume 29, Issue 23, pp 6259–6267 | Cite as

Synthesis of silicon nitride powder through nitrogen gas atomization

  • Jian -Cherng Wuu
  • J. M. Schoenung
Article
  • 71 Downloads

Abstract

The feasibility of synthesizing silicon nitride powder utilizing reactive atomization processing was analysed. The range of times required for the flight time of particles, the cooling rate of the silicon melt, the reaction time of silicon and nitrogen, and the diffusion of nitrogen through silicon nitride layers were obtained and compared. The results of this study indicated that the production of silicon nitride powder through the reactive atomization process would be limited by diffusion of nitrogen through the nitride (ash) layer, assuming the nitride layer was coherent and the unreacted core model was a valid representation of the liquid silicon-silicon nitride system.

Keywords

Silicon Nitride Material Processing Cooling Rate Silicon Nitride 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Nomenclature

k(T)

reaction rate constant at temperature, T(s−1)

k0

Arrhenius coefficient

E

activation energy (kJ mol−1)

R

gas constant

T

temperature (K)

Φα

fraction of normalized conversion of α-phase in time t

Φβ

fraction of normalized conversion of β-phase in time t

kα

reaction rate constant for α-phase (s−1)

kβ

reaction rate constant for β-phase (s−1)

kαi

intrinsic first-order rate constant for α-phase (s−1)

xα

conversion fraction of α-phase in time t

xβ

conversion fraction of β-phase in time t

nα

reaction order for α-phase = 1

nβ

reaction order for β-phase = 0.5

J

diffusion flux (mol m−2 s−1)

D

diffusivity, or diffusion coefficient (m2 s−1 or cm2 s−1)

dC

change in concentration (mol m−3)

dl

change in distance, l (m)

A(g)

gaseous reactant A

B

reactant B (may be solid or liquid)

P

solid product P

b

stoichiometric coefficient of reactant B

p

stoichiometric coefficient of product P

t

time of reaction passed (s)

τ

time for complete reaction of a particle (s)

XB

conversion fraction

rc

core radius (m)

Rp

particle radius (m)

ρB

molar density of reactant B (mol m−3)

kg

mass transfer coefficient between fluid and particle (m s−1)

CAg

concentration of gaseous reactant A (mol m−3)

De

effective diffusion coefficient of gaseous reactant in ash layer (m2 s−1)

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Copyright information

© Chapman & Hall 1994

Authors and Affiliations

  • Jian -Cherng Wuu
    • 1
  • J. M. Schoenung
    • 1
  1. 1.Chemical and Materials Engineering DepartmentCalifornia State Polytechnic UniversityPomonaUSA

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