摘要
为研究金属锰粉的渗氮机理,采用热重分析法分别研究了等温和非等温条件下的氮气中,不同粒度的金属锰粉的氮化反应动力学。研究表明:金属锰粉发生氮化反应的起始温度和氮化锰的分解温度分别为470℃和1 016℃。同一粒度下,随着温度升高,表观速率常数增大,但饱和氮含量反而下降,出现吐氮现象;同一温度下,锰粉粒度越小,氮化速率越快,达到平衡的时间越短。金属锰粉粒度从40目降到100目,氮化反应的表观活化能从189.2 kJ/mol降低到115.2 kJ/mol。不同温度下和不同粒度金属锰粉的氮化过程中界面化学反应是整个过程的控制步骤。
Abstract The kinetics of the nitriding process with different particle size of manganese powder has been studied by using the thermo-gravimetric analysis to research the nitrogen at isothermal and non-isothermal conditions. The initial temperature for manganese powder nitriding begaining and the decomposition temperature of nitrided manganese are 470℃and 1 016℃ respectively. For the same particle size, with the increase of temperature, the nitrding rate constant increased, but the saturated nitrogen content decreased instead. For the same temperature, The finer the manganese powder, the higher nitriding rate was and the shorter the time to reach equilibrium. The particle size of manganese powder varied from 40 meshes to 100 meshes, the apparent activation energy of nitriding dropped from 189.2 kJ/mol to 115.2 kJ/ mol. Interracial chemical reaction was the controlling step in nitriding process of manganese powder with different sizes and different temperatures.
出处
《铁合金》
2014年第1期30-34,共5页
Ferro-alloys
作者简介
罗婷 女,1989年2月出生,北京科技大学冶工程专业在读硕士研究生.研究方向：铁合金.email：liujanhua@metall.wstb.edu.cn.
