Ti-Mo合金的氢化物热解析动力学研究

Study on the Kinetics for Thermal Desorption of Ti-Mo Alloy Hydrides

本文对不同钼含量的钛钼合金Ti(1-x)Mox(x=3,11,20,33,50,at%)氢化物的热解析动力学进行了研究,在高真空金属系统中测试了合金氢化物热解析量随时间的变化关系,应用反应速率分析方法计算了解析速率常数和表观活化能。研究结果发现,氢化物的热解析过程可用一级反应速率方程来描述,而氢原子在合金体相中的扩散是热解析过程的控速步骤。热解析表观活化能随Mo含量的增加而减小,说明氢化物的热稳定性随Mo含量的增加而降低。

Dehydrogenation kinetics of Ti（1-x）Mox （x = 3, 11, 20, 33, 50, at% ） alloy hydrides with various Mo contents was investigated in a constant volume system at the temperature range from 150℃ to 550℃ . Results show that the hydrogen desorption behavior can be described with first-order reaction, and consideration of possible slow steps for H desorption process must be given to mass transport control. The activation energy for dehydrogenation of Ti（1-x） Mox Hydrides （ x = 3, 11, 20, 33, 50, at % ） is 37.9kJ· mol^-1, 30.4kJ· mol^-1 , 32.6kJ· mol^-1, 12.5kJ· mol^-1 and 13.2kJ·mol^-1 , respectively, it decreases with the increase of Mo concent, but the tendency is not obvious before the Mo content is over 33at% .