【作者】 吕俊霞；

【导师】 庄应烘； 刘敬旗；

【作者基本信息】 广西大学 ， 材料物理与化学， 2004， 硕士

【摘要】 通过对151个合金样品进行系统的研究，本文确定了La-Ni-Cr三元系600℃等温截面相图。 本文通过X射线衍射分析法，差热分析法和金相分析法技术测定了La-Ni-Cr三元系600℃等温截面。测定结果表明该截面由10个单相区，17个两相区，8个三相区组成。 在本实验条件下没有观察到La₃Ni，Cr₇Ni₃和Cr₃Ni₂化合物的存在，存在La₇Ni₁₆而不存在LaNi₂，未发现新的三元化合物。在600℃下，Cr在Ni，LaNi₅，La₂Ni₇，LaNi₃，La₂Ni₃，LaNi和La₇Ni₃中的最大固溶度分别约为35，20，15，8，9，9和6at．％，Ni在Cr中的最大固溶度约为3at．％。 本文对LaNi_4.7Si_XCr_0.3-X（X=0.15，0.18，0.22，0.25）型储氢电极合金的吸放氢性能进行了研究。以LaNi_4.7Si_XCr_0.3-X合金粉均匀地涂在泡沫镍上制成的电极片为负极，以烧结Ni（OH）₂为正极，以6mol／L KOH溶液为电解液，制成开口式MH-Ni二次电池，采用自动控制充放电仪——DC-5电池测试仪进行电化学性能测试。研究发现Cr加入到LaNi_4.7Si_0.3中，形成的LaNi_4.7Si_XCr_0.3-X（X=0.15，0.18，0.22，0.25）合金均为CaCu₅型结构，适量的Cr（Cr为0.08）替代LaNi_4.7Si_0.3合金中的Si所形成合金具有优良的综合性能，小电流放电时合金的性能要优于大电流放电时的性能。更多还原

【Abstract】 By discussing the 151 alloy samples, the 600C isothermal section of La-Ni-Cr ternary system phase diagram has been confirmed .The 600C isothermal section of the phase diagram of the La-Ni-Cr ternary system was investigated by X-ray diffraction (XRD), differential thermal analysis (DTA) and optical microscopy techniques. The result showed that the section is composed of ten single-phase regions, seventeen two-phase regions and eight three-phase regions. The La3Ni compound does not exist. At 600C, there is La7Ni16, but not LaNi2 The patterns of Cr7Ni3 and Cr3Ni2 have not been observed. Any new compound hasn’t been found . At 600C, the maximum solid solubility of Cr in Ni, LaNi5, La2Ni7, LaNi3, LaNi, La2Ni3 and La7Ni3 is about 35, 20, 15, 8, 9, 9, and 6at.%Cr, respectively. The maximum solid solubility of Ni in Cr is about 3at.%Ni.In this paper, the hydrogen absorption-desorption propery of LaNi4.7SixCr0.3-x alloys with X=0.15, 0.18, 0.22, 0.25, 0.28 has been investigated. The open recycling batteries were made with LaNi4.7SixCr0.3-x cathode evenly smeared on foam Nickel and Ni(OH)2 anode in the electrolyte of 6mol/L KOK. By analyzing the experiment results from the automatic charge-discharge-DC-5 battery testing instrument, we found that the LaNi4.7SixCr0.3-x(X=0.15, 0.18, 0.22, 0.25, 0.28) alloys were CaCu5structure. And the LaNi4.7SixCr0.3-x alloy possessed excellent properties at Cr=0.08. The battery property is well at little current discharge than big current discharge.更多还原