Morphological change and hydorogen absorption-desorption characterristics of hydorogen-absorbing alloy by meehanical alloying

利用氢化物生成焓与原子半径的关系，设计了10种镍氢二次电池用合金，采用高频熔炼炉制备了设计的Abs系和AB_2系合金，并对其进行了热处理。用砂浆对3种合金（AB_5和AB_2: C15、C14）进行200目压碎，并用球磨机进行机械研磨。研究了合金粉末的晶体结构变化和吸脱附特性，并用球磨机将合金成分的金属粉末制成合金。(1)铸造合金的特性：大多数生产的合金在设计过程中具有电化学特性。(2)从球磨机容器中弹射粉碎合金粉末的方法当球磨机容器的盖子在空气中打开时，合金粉末样品受到氧化。为了防止这种氧化，在球磨机容器中注入一些有机溶剂后取出样品，注入乙醇的样品的电化学特性最好。(3)机械磨削（MG）对合金粉末的影响：MmNi_<41> Co_<0.4> Mn_<0.2> Al_<0.3 Fe_<0.1>（ab5系），Zr_<0.95> Ti_<0.05>(V_<0.10> Ni_<0.57> Mn_<0.28> Cr_<0.05>) 2.1 （AB_2， C15型）和Zr_<0.65> Ti_<0.35> (V_<0.10> Ni_<0.57> Mn_<0.28> Co_<0.05>) 1.82（AB_2， c14型），MG加工时间为5-200（425）小时。随着加工时间的延长，这些合金粉末呈非晶态，加工结束时晶粒尺寸达到几纳米级。P-C-T曲线上的最大氢含量随MG处理时间的增加而降低，高原中心附近的平衡氢压力随MG处理时间的增加而增加。另一方面，电化学容量随MG处理时间的增加而降低。(4)含10%镍粉的合金粉末机械合金化，含10%镍粉的合金放电容量比不含镍粉的合金略有提高

10 kinds of alloys for Ni-MH secondary battery were designed by using the relationship between enthalpy for hydride formation and atomic radius, Designed Abs system and AB_2 system alloys were produced by using high frequency fusion fumace, and these conducted the heat treatment afterwards. 3 kinds of alloys (AB_5 and AB_2 : C15, C14) were crushed under 200 meshes by a mortar, and these samples did the mechanical grinding by using ball mill. Change of crystal structure and absorption-desorption characteristics were examined on these alloy powders In addition, an alloy was also produced from metal powders of alloy constituent element by the ball mill.(1)Characteristics of cast alloys Most of produced alloys had electrochemical characteristics along the design. This fact has proven that the reliability of our ally-design method is high (2)Ejection method of crushed alloy powder from ball mill container Alloy powder sample receives the oxidation, when the cover of the ball mill container … More is opened in the air. In order to prevent this oxidation, the sample was taken out after some organic solvents were injected to the ball mill container, Electrochemical characteristics of the sample which injected ethanol were the best. (3)Effect of mechanical grinding(MG) for alloy powders The alloys used in this study were MmNi_<41> Co_<0.4> Mn_<0.2> Al_<0.3_ Fe_<0.1>(AB_5-system), Zr_<0.95> Ti_<0.05>(V_<0.10> Ni_<0.57> Mn_<0.28> Cr_<0.05>) 2.1 (AB_2, C15 type) and Zr_<0.65> Ti_<0.35> (V_<0.10> Ni_<0.57> Mn_<0.28> Co_<0.05>) 1.82(AB_2, C14-type), and MG processing was carried out for 5-200(or 425) hour. These alloy powder became amorphous state with the increase in processing time and the crystallite size became several nano-meter in the end of processing. The maximum hydrogen content in the P-C-T curve decreased with the increase in MG processing time and the equilibrium hydrogen pressure (near the center of the plateau) tended to increase with the increase in MG processing time. On the other hand, electrochemical capacities decreased with the increase in MG processing time. (4)Mechanical alloying of alloy powder with 10% nickel powder Discharge capacity of the alloy including the 10% nickel powder slightly increased further than the alloy without Ni powder Less