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采用快淬方法制备添加Cu及Nd元素的具有纳米晶和非晶结构的(Mg24Ni10Cu2)100-x Nd x(x=0,5,10,15,20)合金。用X射线衍射(XRD)和高分辨率投射电镜(HRTEM)分析铸态及快淬态合金的相组成及结构,并研究Nd含量和快淬速率对合金相结构及吸氢性能的影响。结果表明,快淬态无Nd合金为纳米晶结构,而含Nd的快淬态合金则为纳米晶和非晶结构,表明添加Nd促进了合金的非晶形成能力。添加Nd及快淬处理均显著地促进了合金的气态及电化学动力学性能。添加Nd及快淬处理加快了氢原子在合金体内的扩散速率,但是均降低了合金电极表面的电荷传递性能,从而使得合金的高倍率放电性能(HRD)随着Nd含量和快淬速率的增加先上升而后下降。
A (Mg24Ni10Cu2) 100-x Nd x (x = 0,5,10,15,20) alloy with nanocrystalline and amorphous structure added with Cu and Nd elements was prepared by quenching method. The phase composition and structure of as-cast and quenched alloys were characterized by X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM). The effects of Nd content and quenching rate on the phase structure and hydrogen absorption properties of the alloys were also investigated. The results show that the quenched Nd-free alloy is nanocrystalline, while the Nd-containing quenched alloy is nanocrystalline and amorphous, which indicates that the addition of Nd accelerates the amorphous formation. Adding Nd and quenching significantly promoted the gas and electrochemical kinetics of the alloy. The addition of Nd and quenching accelerated the diffusion rate of hydrogen atoms in the alloy, but all decreased the charge transfer performance of the alloy electrode, which led to the high rate discharge (HRD) of the alloy with the increase of Nd content and quenching rate First rise and then fall.