非化学计量La(NiMn)5.6合金的储氢性能
Hydrogen Storage Properties of La(NiMn)5.6 Alloys
吴静然, 刘春哲, 王国永
点击:3479次 下载:0次
作者单位:(承德石油高等专科学校 机械工程系, 河北 承德 067000)
中文关键字:La(NiMn)5.6合金; 贮氢性能
英文关键字:La(NiMn)5.6 alloys; hydrogen storage properties
中文摘要:借助X- ray及吸放氢性能测试装置研究了处理条件对非化学计量 La(NiMn)5.6合金的结构、活化性能、吸氢容量和平台压力等性能的影响,测试了不同温度(298~333 K)下合金吸放氢性能的PCT曲线。结果表明,无论退火处理还是快速凝固,合金的点阵常数a缩短,c伸长,单胞体积增大。与常规熔铸相比,退火处理和快速凝固均提高了合金的活化性能,且都大大提高了合金的贮氢性能。都使平台压力降低,但快速凝固吸氢量有所降低;快速凝固+低温退火合金的吸氢量最大,在298 K、3.3 MPa下,PCT的最大吸氢原子比(H/M)为1.24。
英文摘要:Hydrogen storage alloys with over-stoichiometric La(NiMn)5.6 were prepared by annealing, melt-spinning. The hydrogen performance and structure of La(NiMn)5.6 hydrogen storage alloys were investigated by pressure-composition isotherms, XRD and atomic parameters. It is found that the increase of unit cell volume decreases the plateau pressure and increases hydrogen storage capacity. Pressure-composition-temperature (P-C-T) relations of La(NiMn)5.6 alloy were studied under isothermal dynamic conditions of 298 ~333 K. The hydrogen absorption / desorption properties were determined by pressure-composition isotherms under the temperature of 298~333 K. The heat-treatment and spinning measurement can improve initial activation of the alloys under moderate conditions. After heat-treatment, the hydrogen performance of La(NiMn)5.6 alloys could be further improved, low equilibrium pressure and higher hydrogen capacity. However, there is little decreases in hydrogen capacity of spun alloy. The maximum hydrogen capacity per metal atom (H/M =1.24) was calculated from the PCT diagram at 298 K and 3.3 MPa hydrogen pressure, which is spinning + low temperature annealing.