| Abstract: | 為拓展儲氫合金的應用，本研究自行建構一金屬氫化物氫壓縮機系統，此系統設計可進行單階段或二階段氫壓縮測試模式，且可在單階段氫壓縮時連續釋放高壓氫氣，並選用AB5型La0.5Ce0.5Ni5-xAlx (x=0, 0.1, 0.2)與AB2型Ti1-yZryMn0.8Cr1.2 (y= 0.1, 0.2)系列合金，作為單階段氫壓縮機材料。 合金以真空電弧熔煉法熔配，經由X光粉繞射分析、PCI測試、吸放氫動力學測試及Van’t Hoff曲線探討後可知，La0.5Ce0.5Ni5-xAlx系列合金中，由於Ce取代La造成合金晶格體積變小，因此提高合金吸放氫平台壓，但遲滯也跟著變大，而隨著Al取代量增加可略為降低遲滯影響，但也造成吸放氫平台壓下降。而在Ti1-yZryMn0.8Cr1.2合金中，晶格體積隨著Zr含量增加而變大，而大幅降低合金吸放氫平台壓。 由二系列合金中，選La0.5Ce0.5Ni5與Ti0.9Zr0.1Mn0.8Cr1.2合金以單階段氫壓縮機進行測試，可在100℃下分別達到117atm與132atm放氫壓力，並於140℃時，二者皆可達到200atm放氫壓力，而Ti0.9Zr0.1Mn0.8Cr1.2合金於各溫度下放氫壓力較高且放氫動力學較佳，明顯優於La0.5Ce0.5Ni5合金。 In order to expanded applications of hydrogen storage alloys, a metal hydride hydrogen compressor was developed in this work. The compressor operated with two mode, single-stage compression and double-stages compression. In single-stage mode, the compressor could supply high-pressure hydrogen continually. Materials selected was AB5-based La0.5Ce0.5Ni5-xAlx (x=0, 0.1, 0.2) alloys and AB2-based Ti1-yZryMn0.8Cr1.2 (y= 0.1, 0.2) alloys for single-stage compression. All samples were prepared by arc-melting in argon atmosphere and characterized by XRD, PCI tests, kinetic tests and discussed with Van’t Hoff equations. In La0.5Ce0.5Ni5-xAlx (x=0, 0.1, 0.2) series alloys, the replacement of La by Ce decreased unit cell volume of alloys and resulted in plateau pressure increased. And Ce substitution also increased hysteresis effect. With increased Al contents, both plateau pressure and hysteresis were decreased. In Ti1-yZryMn0.8Cr1.2 (y= 0.1, 0.2) series alloys, Ti was replaced by Zr, and with increased Zr contents, the plateau pressure was decreased. These resulted from the increase of unit cell volume caused by Zr substitution. From two series alloys, La0.5Ce0.5Ni5 and Ti0.9Zr0.1Mn0.8Cr1.2 were selected for single-stage compressor. In the compression tests, La0.5Ce0.5Ni5 and Ti0.9Zr0.1Mn0.8Cr1.2 could produce 117atm and 132atm hydrogen at 100℃ respectively. And when the temperature was raised to 140℃, both two alloys could produce 200atm hydrogen. In comparison of these two alloys, the compression properties of Ti0.9Zr0.1Mn0.8Cr1.2 were better than La0.5Ce0.5Ni5. |
