摘要
以d50为5μm的AlN微粉为原料,在气氛组成为4/5N2+1/5O2、流量为55mL/min、升温速率为10℃/min的条件下,采用TG-DTA和XRD分析对AlN微粉的非等温氧化反应过程和动力学参数进行研究。结果表明:d50为5μm的AlN微粉明显氧化增重过程约为900℃之后,其反应过程受反应机制和扩散机制交替控制;其非等温氧化反应动力学参数分别为:活化能E约为417.4kJ/mol,反应级数n约为2.9,指前因子A约为3.47×1012h-1。AlN微粉的非等温氧化反应动力学结果显示,较小的活化能E和较大的指前因子A决定了AlN微粉在高温和空气条件下易氧化、且具有较大的氧化反应速率。理论计算所得氧化增重率曲线与实测TG曲线重合,表明由实验数据分析所建立的动力学方程是合理的。
The process and dynamics parameters of non-isothermal oxidation of AlN powder（d50=5μm） were studied by TG-DTA and XRD in atmosphere of 4/5N2 and 1/5O2 mixture with flow rate of 55mL/min and heating rate of 10℃/min.The results showed that the AlN powder obviously began to be oxidated and its mass increased over 900℃.The process of dynamics of oxidation reaction between AlN and O2 was controlled alternately by reaction and diffusion.Non-isothermal oxidation dynamics parameters（activation energy E,reaction orders n and pre-exponential factor A） of the AlN powder were obtained by the experimental data.E equals about 417.4kJ/mol,n about 2.9 and A about 3.47×1012h-1.Due to smaller activation energy E and larger pre-exponential factor A in dynamics parameters of AlN powder non-isothermal oxidation,AlN powder is easily oxidated with larger oxidation reaction rate at high temperature and air.Actual measurement thermogravimetric curve is in agreement with theoretical calculation.It shows that the dynamics equation based on these dynamics parameters data of non-isothermal oxidation of d50=5μm AlN powder is reasonable.
出处
《材料工程》
EI
CAS
CSCD
北大核心
2011年第4期29-32,37,共5页
Journal of Materials Engineering
基金
国家自然科学基金资助项目(50872029)
河北省自然科学基金资助项目(E2010000960)
