بررسی ترموسینتیکی اکسیداسیون پودر نیترید آلومینیوم

نویسندگان

1 , Materilas and Energy Research Center

2 composite, malek-e-ashtar university of technology

3 material Science and Engineering, Sharif university of technology


عنوان مقاله [English]

Thermokinetic investigation of the oxidation of aluminum nitride powder

چکیده [English]

Aluminum nitride (AlN) possesses excellent physical properties such as low thermal expansion coefficient
and high thermal conductivity and electrical resistivity. In spite of large application in refractory industry, this material
tends to be oxidized at high temperature in the environmental atmosphere which affects on its long-term service. Study
of oxidation behavior of this material is therefore of high importance from both fundamental and application point of
view. In the current research, the oxidation kinetic of AlN powder was explored by means of thermogravimetry. Non-isothermal tests results showed that oxidation of nano-scale powders starts from lower temperatures in compare of
micro-scale ones. Using iso-thermal data, the oxidation kinetic was discussed by means of corresponded equations and
controlling mechanism was identified consequently. To elaborate the oxidation kinetic, the process was divided by two
parts; using the first-order equation (nucleation and growth mechanism) in the initial stages following by Jander
equation for diffusion mechanism. Activation energy was calculated in either steps showing reasonable consistency
with the literature. The effect of temperature on oxidation kinetic of micro-scale powder and effect of reduction in
particle size (for a same temperature) was shown by mathematical equation in each step.

کلیدواژه‌ها [English]

  • Kinetics
  • oxidation
  • Aluminum nitride
  • Nano powder
  • Thermogravimetry