铁取代部分铬对TiVCrMn合金储氢性能的影响

Effects of Partial Substitution of Fe for Cr on Hydrogen Storage Performance of TiVCrMn Alloys

38Ti-30V-18Mn-14Cr合金具有比较大的吸氢量,但是其放氢平台太低,尤其是有效放氢量太少。Fe有利于合金放氢平台提高,所以本文研究了Fe取代部分Cr对该合金的吸/放氢性能的影响。X射线衍射(XRD)分析表明,随Fe取代Cr的量的增加,合金的相组成经由单一的体心立方(bcc)相逐渐转变为bcc与Laves两相共存,合金bcc相的晶格常数和晶胞体积减小。吸放氢性能曲线表明,Fe取代Cr后合金的最大吸氢量降低,但是合金的放氢平台显著升高,合金的有效放氢量增大。对于38Ti-30V-18Mn-10Cr-4Fe合金,在298K吸氢、353K放氢的条件下,有效放氢量达到最大为1.51%。

38Ti-30V-18Mn-14Cr alloy had good maximum hydrogen absorption capacity, but its hydrogen desorption plateau pressure was too low, and its effective hydrogen desorption capacity was unsatisfactory. Fe was helpful for alloys to get high hydrogen desorp- tion plateau pressure, so the effects of partial substitu- tion of Fe for Cr on hydrogen storage properties were investigated to improve the alloy performance. It was found that with the increase of Fe addition, the Cl4 Laves phase was brought into bcc solid solution, and both the lattice parameters and the unit cell volume of bcc phase decreased. The PCT curves showed that the maximum hydrogen absorption capacity reduced, but the hydrogen desorption plateau pressure was improved and the effective hydrogen desorption capacity increased. For the 38Ti-30V-18Mn-10Cr4Fe alloy, the effective hydrogen desorption capacity reached the maximum value of 1.51%.