储氢材料Kβ-MgH2的动态真空安定性研究

Study on dynamic vacuum stability of Kβ-MgH2 hydrogen storage material by DVST

为研究储氢材料Kβ-MgH2分解放气过程,在以10℃为步长,80~130℃区间内,48,120 h时间条件下,采用基于传感器压力变化计算被测物质分解放气量的动态真空安定性测试(DVST)方法,得到在上述条件下Kβ-MgH2分解过程中的压力变化、Kβ-MgH2的单位分解放气量和在不同研究温度下的分解放气规律,分析DVST测试时长的设置方法,验证Kβ-MgH2在时温等效系数为2.5时的时温等效特性。结果表明:在选定的测试条件下,Kβ-MgH2分解放气量稳定,单位分解放气量与样品状态无关;Kβ-MgH2单位质量放气量先快速增加,随后趋于平稳,测试温度越高,Kβ-MgH2放气速率越快,单位质量放气量越大;根据选定的测试温度和温度变化步长,可知Kβ-MgH2分解放气过程具有时温等效性。

In order to study the outgassing process of hydrogen storage material Kβ-MgH2,this paper studied the decomposition process of Kβ-MgH2 at 10℃for 48 h and 120 h at 80℃~130℃,the dynamic vacuum stability test(DVST)method calculating the decomposition deflation volume of tested material based on the change of sensor pressure was used to obtained the pressure change during the decomposition process of Kβ-MgH2 under the above conditions,the unit decomposition deflation volume of Kβ-MgH2,and the decomposition deflation laws under different research temperatures.The setting method of DVST test duration was analyzed,and the time-temperature equivalent characteristics of Kβ-MgH2 when the time-temperature equivalent coefficient was 2.5 were verified.The results showed that under the selected test conditions,the decomposition deflation volume of Kβ-MgH2 was stable,and the unit decomposition deflation volume had nothing to do with the state of sample.The unit mass deflation volume of Kβ-MgH2 first increased rapidly,and then tended to stabilize.The higher the test temperature,the faster the deflation rate of Kβ-MgH2,and the larger the unit mass deflation volume.According to the selected test temperature and temperature change step,the decomposition deflation process of Kβ-MgH2 was time-temperature equivalent.