吸放氢性能的影响
(浙江大学 材料与化工学院, 杭州 310027)
摘 要: 研究了不同条件下机械球磨改性处理对Ti46V44Fe10储氢合金相结构和吸放氢性能的影响。 X射线衍射及扫描电镜分析表明: Ti46V44Fe10铸态合金由单一的体心立方(BCC)结构的固溶体组成; 经过1 h的干法球磨(未添加四氢呋喃THF)后, 合金中出现了微量的α-Ti第二相, 主相晶胞体积减小, 合金颗粒明显减小并发生团聚; 经过0.5、 1、 20 h的湿法球磨(添加THF)后, 合金中分别出现了含量不等的α-Ti第二相, 主相晶胞体积逐渐减小,颗粒尺寸明显减小。 储氢性能测试表明: 球磨改性处理能有效地改善合金的活化性能, 活化次数由球磨前的4次降至球磨后的1~2次; 短时间(0.5 h, 1 h)湿磨还能改善Ti46V44Fe10合金的吸放氢容量; 但1 h干磨和20 h湿磨则会明显降低合金的吸放氢容量。
关键字: Ti-V-Fe合金; 球磨改性; 相结构; 储氢性能
hydriding/dehydriding behaviour of
Ti46V44Fe10 alloy
(College of Materials Science and Chemical Engineering,
Zhejiang University, Hangzhou 310027, China)
Abstract: The change in the phase structure and hydrogen storage properties of Ti46V44Fe10 alloy after modification by ball-milling under different conditions were investigated. XRD and SEM analysis show that the as-cast alloy consists of a single solid-solution phase with BCC structure. The modified alloy dry-milled without tetrahydrofuran (THF) for 1 h has a little α-Ti secondary phase besides the BCC main phase, the unit cell volume of main phase decreases, the particle size decreases and the powder appears aggregation. The modified alloys wet-milled in THF for 0.5 h, 1 h or 20 h also have some α-Ti secondary phase besides the BCC phase, the unit cell volume of main phase decreases with the increase of ball-milling time, and the particle size decreases obviously. It is found that the ball-milling can improve the activation behaviour of the Ti46V44Fe10 alloys effectively. Comparing with the as-cast alloy, the hydrogen absorption/desorption capacities of the alloys wet-milled for 0.5 h or 1 h increase, but the hydrogen absorption/desorption capacities of the alloy dry-milled for 1 h or wet-milled for 20 h decrease.
Key words: Ti-V-Fe alloy; ball-milling; phase structure; hydrogen storage property