【摘要】 研究了x(Zr)及热处理工艺对LaNi(4.2+5x)Mn0.4Al0.4Zrx储氢合金微观组织与电化学性能的影响.结果表明:添加Zr元素后该储氢合金中均出现Zr(Ni,Al,Mn)5第二相,并且第二相的含量随x的增大而增多.当x=0.4时,经热处理后合金中的第二相沿主相晶界呈网状分布,而且其韧性很好.由于第二相对主相起到了防腐蚀保护作用,并降低了充放电过程中晶格畸变引起的合金粉化的速度,从而使循环稳定性显著提高,但由于第二相不是吸氢相,对电化学容量没有贡献,因此它的出现使合金的放电容量降低.更多还原

【Abstract】 The effects of the content of Zr and the process of heattreatment of the alloy on the structure and electrochemical properties of hydrogenstoring alloys LaNi(4.2+5x)Mn0.4Al0.4Zrx are investigated. The results show that a secondary phase Zr(Ni,Al,Mn)5 appears in the alloy and its amount increases with the magnitude of x.The secondary phase with x=0.4 in the heattreated alloy distributes along the grain boundary of the main phase forming a tough network to protect the main phase from corrosion and decrease the speed of pulverization of the alloy due to lattice distortion during charging and discharging, process, so that making the alloy of a better cycle stability. However, the secondary phase is not of hydrogen absorption, so that the discharge capacity of such alloy decreases.更多还原