碳对TiMn_(1.25)Cr_(0.25)合金储氢行为的影响

Effect of carbon on hydrogen storage performances of TiMn_(1.25)Cr_(0.25) alloy

研究了碳对TiMn1.25Cr0.25合金的活化与吸放氢性能的影响。碳的添加改善了合金的活化性能。俄歇电子能谱深度剖析结果表明,碳的添加没有抑制合金表面氧化层的形成,但导致了合金表面的Mn/Ti比率接近于合金的基体成分,这可能是合金活化性能改善的原因之一。PCT测试结果表明,随着合金中碳含量的增加,合金的吸放氢平台压力上升,同时吸氢量有所下降,这是由于碳的添加导致合金晶格参数减小以及合金中TiC相形成所致。随着合金中碳含量的增加,TiMn1.25Cr0.25合金的吸放氢循环衰减减少。

The effect of carbon addition on hydrogen storage performances of TiMn_(1.25)Cr_(0.25) alloy was investigated. The activation of TiMn_(1.25)Cr_(0.25) alloy becomes easier with increasing carbon content. Auger electron spectroscopy(AES) results show that the carbon addition does not restrain the formation of oxide layer on the surface of TiMn_(1.25)Cr_(0.25) alloy, but causes the Ti/Mn ratio of alloy top surface close to the matrix, which probably is one of the reasons for the improvement of alloy activation performance. The PCT results present that, with increasing carbon contents, the hydrogen absorption-desorption plateau pressure increases and the hydrogen absorption capacity decreases, which results from the decrease of lattice parameters and the formation of TiC phase. In addition, the cycle-life of hydrogen absorption-desorption becomes longer when the carbon concentration is increased.