LaFe11.6Si1.4吸氢动力学及其氢化物稳定性研究

Hydrogen Absorption Kinetics of LaFe11.6Si1.4 Alloy and Its Hydride Stability

摘要:

采用P-C-T测试仪研究了磁致冷材料LaFe11.6Si1.4合金在不同温度下的吸氢动力学性能，发现在30~80 ℃范围内，温度升高有利于LaFe11.6Si1.4氢化物的形成。LaFe11.6Si1.4合金氢化物在不同温度下的放氢P-C-T曲线表明：压力变化在0~4 MPa内，没有出现放氢平台，随着压力降低，合金中含氢量逐渐降低。采用热分析方法研究温度变化后合金氢化物的热稳定性，TG曲线表明：温度升高，合金中的氢逐渐放出，在室温至60 ℃以内，放氢量较少，超过60 ℃后，温度升高放氢量加大。作者提出可以通过升温或降压的手段有效调节合金中的氢含量，进而调控合金居里温度的思路

Abstract:

The hydrogen absorption kinetics of the magnetic refrigeration material LaFe11.6Si1.4 alloy at different temperatures was investigated by the P-C-T testing. It is found that increasing temperature conduces to form the hydride of LaFe11.6Si1.4 at 30~80 ℃. The hydrogen desorption P-C-T curves of LaFe11.6Si1.4 hydrides at different temperatures show that no hydrogen-desorption platform appears at a pressure of 0~0.4 MPa, and the hydrogen in the alloy gradually decreases with the decreasing of pressure. A thermal analysis is used to study the thermal stability of temperature for the hydride. The TG curve shows that the hydrogen in the alloy gradually releases with the increase of temperature up to a relatively little value at 60 ℃, then increases above 60 ℃. An effective method to regulate the hydrogen content in the alloy by increasing temperature or decreasing pressure then to controll the Curie temperature of alloy is presented in this article