【作者】 李慧；

【导师】 王新华；

【作者基本信息】 浙江大学 ， 材料学， 2010， 硕士

【摘要】 本文对氢化物复合高压储氢器用储氢合金及高压金属氢化物压缩机用储氢材料的研究进展进行了全面综述。在此基础上,选择具有高分解压和高储氢容量的AB2型Ti-Cr-Mn(Fe)基多元储氢合金为研究对象,系统研究了合金的晶体结构、储氢性能、以及压缩性能。通过吸放氢性能测试和XRD分析,研究了Cr/Mn比、Cr/Fe比和电子浓度e/a对合金吸放氢特性的影响,以及Fe、V、Cu元素的添加对合金储氢性能和相结构的影响规律,优化出性能优良、适用于氢化物复合高压储氢器和金属氢化物高压压缩器的储氢合金,采用研制的储氢合金设计并研制出性能优异的工作压力为40MPa的氢化物复合高压储氢器和增压压力超过70MPa的金属氢化物高压压缩器样机。对Ti0.9Zr0.15CrxMn1.8-xV0.2 (x=1.4,0.9,0.5,0.2)和Ti0.95Zr0.05CrxMn1.75-xV0.2Fe0.05(x=1.1,0.9,0.7,0.5,0.3)系多元合金的研究结果表明：合金的主相均为C14 Laves相,并且存在少量的杂相。合金的晶格常数和晶胞体积都随Cr/Mn比的减小呈线性递减。随着Mn含量增加,Ti0.9Zr0.15CrxMn1.8-xV0.2系列合金的吸放氢平台压升高,倾斜因子减小,但滞后因子增大。Ti0.95Zr0.05CrxMn1.75-xV0.2Fe0.05系列合金吸放氢平台平坦且范围宽,吸氢量大,放氢率高。随着Cr/Mn比的减小和电子浓度e/a的增加,吸放氢平台压升高,吸放氢平台倾斜度减小,但滞后因子增大。其中Ti0.95Zr0.05Cr0.7Mn1.05V0.2Fe0.05合金的在273K时最大储氢量达到2.09wt.%,吸放氢平台压分别为2.13MPa、1.17MPa,滞后因子为0.60,具有优异的储氢特性,适合于作为氢化物复合高压储氢器用储氢合金。采用该合金与轻质高压储氢容器复合制作了氢化物复合高压储氢器,室温下体积储氢密度和质量储氢密度分别达到29.7kg H2/m-3和2.4wt.%。对Ti0.8Zr0.2Cr(2-x)/2Fe(2-x)/2Vx(x=0,0.1,0.2)和Ti0.8Zr0.2Cr1.9-xFexV0.1 (x=0.5,0.7,0.95,1.1,1.2)系列合金的研究结果表明：合金吸放氢前后都是由六方晶系的MgZn2(C14)结构组成,随着Cr/Fe比的降低,合金的晶格常数和晶胞体积呈线性递减,合金的吸放氢曲线均具有较宽的压力平台和良好的平台特性。随着V、Cu元素的引入,Ti0.8Zr0.2Cr(2-x)/2Fe(2-x)/2Vx系合金的吸氢量和吸氢速率显著提高。适量的V可以减小合金的滞后性和平台倾斜度,但是Cu的加入会增加滞后因子和倾斜度程度。当部分Ti被Zr替代时,吸氢量有所提高,但滞后性增加。同时,Ti0.8Zr0.2Cr1.9-xFex-V0.1(x=0.5,0.7,0.95,1.1,1.2)系列合金随着Cr/Fe比的减小,储氢量增加,但合金活化次数增加,饱和吸氢时间延长,a、B两相区域变宽,滞后性增加,平台倾斜度降低。其中,Ti0.8Zr0.2Cr0.95Fe0.95V0.1合金动力学性能良好,具有较为平坦的压力平台,在258K时最大储氢量为1.72wt.%,吸放氢平台压分别为2.54MPa、2.32MPa,滞后因子为0.09,吸放氢时的生成焓ΔH分别为-19.6kJ/mol H2和-20.5J/mol H2,该合金适合于作为高压氢化物压缩用储氢合金。采用该合金作为第二级高压压缩合金与AB5型稀土系合金La0.35Ce0.45Ca0.2Ni4.95Al0.05(作为第一级压缩合金)配对,设计并制作了容量为2000L的二级高压氢化物压缩机样机。当温度升高到423K时,该高压氢化物压缩机可提供74.5MPa的高压氢。更多还原

【Abstract】 In this thesis, the recent research and development on hydrogen storage alloys for high-pressure metal hydride hybrid hydrogen storage vessel and high-pressure metal hydride compressor were exhaustively reviewed. AB2 type Ti-Cr-Mn(Fe)-based multi-component alloys with high hydrogen absorption/desoprtion plateau pressure was selected as the study object of this work, and the microstructures, hydrogen storage properties and compression properties were studied systematically. By means of hydrogen storage properties measurements and XRD analysis, the effect of alloy composition (including Cr/Mn ratio, Cr/Fe ratio, partial substitution of Cr and/or Mn by Fe, V and Cu) and averaged number of outer electrons (e/a) on the phase structure and the hydrogen storage characteristics were investigated. Alloys with good hydrogen storage properties were developed for metal hydride hybrid high-pressure hydrogen storage vessel and high-pressure hydrogen compressor. With the developed hydrogen storage alloys, we have built a metal hydride hybrid high-pressure hydrogen storage vessel with working pressure of 40MPa and a high-pressure metal hydride hydrogen compressor which can supply 70MPa high-pressure hydrogen.For Ti0.9Zr0.15CrxMn1.8-xV0.2 (x=1.4,0.9,0.5,0.2) and Ti0.95Zr0.05CrxMn1.75-xV0.2Fe0.05 (x=1.1,0.9,0.7,0.5,0.3) multi-component alloys, the experimental results show that all alloys consist of C14 Laves phase, and the lattice constants and cell volume of the alloys decrease as Cr/Mn ratio decreases. For Ti0.9Zr0.15CrxMn1.8-xV0.2 alloys, as Mn content increases, the hydrogen absorption/desorption plateau pressure increases and the slope factor decreases, but the hysteresis factor increases.Ti0.95Zr0.05CrxMn1.75-xV0.2Fe0.05 alloys have flatter and wider p-c-T plateau region, as well as larger hydrogen storage capacity and higher hydrogen desorption rate. It is found that as Cr/Mn ratio decreases and e/a increases, the hydrogen absorption/desorption plateau pressure and the hysteresis factor increases, the slope factor decreases remarkably. Ti0.95Zr0.05Cr0.7Mn1.05V0.2Fe0.05 alloy demonstrates fairly ideal properties with hydrogen absorption capacity of 2.09 wt.% at 273K and hydrogen absorption and desorption plateau pressure of 2.13MPa and 1.17MPa, respectively. Combined this alloy with a lightweight high-pressure hydrogen storage vessel, a metal hydride hybrid high-pressure hydrogen storage vessel with working pressure of 40MPa was made. Its volumetric hydrogen storage density and gravimetric hydrogen storage density reached 29.7kg·m-3 and 2.4 wt%, respectively. For Ti0.8Zr0.2Cr(2-x)/2Fe(2-x)/2Vx (x=0,0.1,0.2) and Ti0.8Zr0.2Cr1.9-xFexV0.1 (x=0.5,0.7, 0.95,1.1,1.2) alloys, the experimental results show that all of these alloys have a main phase of C14 type Laves phase, and the cell volume decrease with the decrease of Cr/Fe ratio. Ti0.8Zr0.2Cr(2-x)/2Fe(2-x)/2Vx possess flat plateau region and high plateau pressure, after adding small amounts of V and Cu, their hydrogen storage capacity and hydrogen absorption rate are improved. When adding a small amount of V, the hydrogen storage capacity increases and the plateau properties are improved. But when small amounts of Cu is added, the hysteresis factor and slope factor increase even though a little increment in hydrogen storage capacity. Partial substitution of Ti by Zr can improve the plateau properties but increase the hysteresis. Ti0.8Zr0.2Cr0.95Fe0.95V0.1 alloy show admirable performance with hydrogen absorption capacity of 1.72wt.% at 258K, and its hydrogen absorption and desorption plateau pressure are 2.54MPa and 2.32MPa, respectively, its hydrogen absorption and desorption enthalpy are -19.6kJ/molH2 and -20.5J/molH2, respectively. With La0.35Ce0.45Ca0.2Ni4.95Al0.05 as the first stage hydrogen compression alloy and Ti0.8Zr0.2Cr0.95Fe0.95V0.1 as the second stage hydrogen compression alloy, a double-stage hydride hydrogen compressor was designed and built. When the temperature of the hydride beds is increased to 423K, the metal hydride compressor can supply hydrogen with pressure of over 70MPa.更多还原