Volume 34,Issue 11,2005 Table of Contents
2005, 34(11):1681-1685.
Abstract:
The crystal structure of lithium cobalt system, lithium manganese system and lithium nickel system, together with the promising latent material of polymer and iron salt contained polyanions were reviewed. The characters of electrical properties were analyzed with the point of crystal structure. On this basis, the requirements in crystal structure for good positive electrode were suggested.
The crystal structure of lithium cobalt system, lithium manganese system and lithium nickel system, together with the promising latent material of polymer and iron salt contained polyanions were reviewed. The characters of electrical properties were analyzed with the point of crystal structure. On this basis, the requirements in crystal structure for good positive electrode were suggested.
2005, 34(11):1686-1689.
Abstract:
铀和铀合金用涂层不同于通常的耐高温涂层，不仅要求具有耐高温和抗热震，还要求涂层与基体和熔体之间具有化学稳定性。分析了熔炼过程中的铀和铀合金的碳污染源和污染机理。表明炉内的CO和涂层的缺陷面积是熔体碳污染的主要来源，而熔体的碳污染对涂层缺陷面积更敏感，并指出了涂层的设计要求。不同涂层材料体系和制备方法的比较表明：单层涂层不能满足高性能高质量铀和铀合金熔炼的要求；内层为阻挡层（碳化物或难熔金属W，Nb，Mo等），外层为Y2O3的复合涂层，能够满足高温铀合金的熔炼要求，是铀和铀合金用涂层的发展趋势。
铀和铀合金用涂层不同于通常的耐高温涂层，不仅要求具有耐高温和抗热震，还要求涂层与基体和熔体之间具有化学稳定性。分析了熔炼过程中的铀和铀合金的碳污染源和污染机理。表明炉内的CO和涂层的缺陷面积是熔体碳污染的主要来源，而熔体的碳污染对涂层缺陷面积更敏感，并指出了涂层的设计要求。不同涂层材料体系和制备方法的比较表明：单层涂层不能满足高性能高质量铀和铀合金熔炼的要求；内层为阻挡层（碳化物或难熔金属W，Nb，Mo等），外层为Y2O3的复合涂层，能够满足高温铀合金的熔炼要求，是铀和铀合金用涂层的发展趋势。
2005, 34(11):1690-1693.
Abstract:
用硝酸钯铵((NH4)2Pd(NO3)4)热分解法制得了钯含量为44.5%±0.1%(质量分数,下同)的涂钯硅藻土(Pd/K)。分别在293K,303K,313K下测定了不同氢钯比的动力学曲线。结果表明,在常温下Pd/K与氢分为初始快反应和后期长时间的慢反应2个阶段。其中,快速反应阶段的吸氢动力学曲线在1min内满足以下关系式:P=P0+(P0–Pe)·exp(Kt),符合解离吸附机理。在α及β相区的吸氢速率常数随氢钯比增加而呈线性增加,而坪台区与两相区转变点附近的速率常数呈减小趋势。当氢钯比为0.0015~0.0175时,活化能由2.82kJ·mol-1上升至10.45kJ·mol-1。
用硝酸钯铵((NH4)2Pd(NO3)4)热分解法制得了钯含量为44.5%±0.1%(质量分数,下同)的涂钯硅藻土(Pd/K)。分别在293K,303K,313K下测定了不同氢钯比的动力学曲线。结果表明,在常温下Pd/K与氢分为初始快反应和后期长时间的慢反应2个阶段。其中,快速反应阶段的吸氢动力学曲线在1min内满足以下关系式:P=P0+(P0–Pe)·exp(Kt),符合解离吸附机理。在α及β相区的吸氢速率常数随氢钯比增加而呈线性增加,而坪台区与两相区转变点附近的速率常数呈减小趋势。当氢钯比为0.0015~0.0175时,活化能由2.82kJ·mol-1上升至10.45kJ·mol-1。
4 The Parameters of Noble Metal and Calculations of Dilute Solution Heat for Noble Metal Binary Alloys
2005, 34(11):1694-1697.
Abstract:
The modified embedded atom method (MEAM) has been applied to parameters calculated for noble metals Cu, Ag Au, Ni, Pd, Pt, Rh, Ir. The parameters of those elements were obtained. The elastic constants, mono-vacancy formation energy, energy difference between face central cubic structure and body central cubic, binding energies of divacancy were calculated. The dilute solution heat of noble binary alloys were also calculated with the present MEAM model. The calculated results were compared with the available experimental data and the results of other theories, which the agreement is reasonable.
The modified embedded atom method (MEAM) has been applied to parameters calculated for noble metals Cu, Ag Au, Ni, Pd, Pt, Rh, Ir. The parameters of those elements were obtained. The elastic constants, mono-vacancy formation energy, energy difference between face central cubic structure and body central cubic, binding energies of divacancy were calculated. The dilute solution heat of noble binary alloys were also calculated with the present MEAM model. The calculated results were compared with the available experimental data and the results of other theories, which the agreement is reasonable.
2005, 34(11):1698-1702.
Abstract:
利用XRD，DTA和DSC分析了机械合金化80．7W-13．2Ni-6．1Fe（at％，下同）合金的相变和热稳定性。结果表明：球磨20h和60h的粉末在加热过程中发生不同的相变化。球磨60h粉末在退火过程中除了晶体缺陷和应力释放等过程以外，有明显的非晶晶化和NiW相析出过程。同时，机械合金化可以降低粉末的烧结温度，同未球磨粉末相比，球磨20h和60h的80．7W-13．2Ni-6．1Fe合金液相出现的温度均降低了200℃以上。
利用XRD，DTA和DSC分析了机械合金化80．7W-13．2Ni-6．1Fe（at％，下同）合金的相变和热稳定性。结果表明：球磨20h和60h的粉末在加热过程中发生不同的相变化。球磨60h粉末在退火过程中除了晶体缺陷和应力释放等过程以外，有明显的非晶晶化和NiW相析出过程。同时，机械合金化可以降低粉末的烧结温度，同未球磨粉末相比，球磨20h和60h的80．7W-13．2Ni-6．1Fe合金液相出现的温度均降低了200℃以上。
2005, 34(11):1703-1707.
Abstract:
研究了机械合金化制备的纳米晶WC-10Co复合粉末的真空烧结特征，分析了孔隙度、显微硬度与烧结时间和温度的关系，考察了改性ZrO2纳米粉体对烧结的作用。结果表明：在1325℃，15min的烧结条件下，样品的相对密度达到了98.6％；显微硬度随着烧结时间的延长和烧结温度的升高先增加后降低，在1325℃烧结15min条件下，合金的最大硬度为22950MPa；改性ZrO2纳米粉体既有利于晶粒长大的控制，同时又有利于材料致密化的进行，可以显著的提高烧结合金的性能。
研究了机械合金化制备的纳米晶WC-10Co复合粉末的真空烧结特征，分析了孔隙度、显微硬度与烧结时间和温度的关系，考察了改性ZrO2纳米粉体对烧结的作用。结果表明：在1325℃，15min的烧结条件下，样品的相对密度达到了98.6％；显微硬度随着烧结时间的延长和烧结温度的升高先增加后降低，在1325℃烧结15min条件下，合金的最大硬度为22950MPa；改性ZrO2纳米粉体既有利于晶粒长大的控制，同时又有利于材料致密化的进行，可以显著的提高烧结合金的性能。
2005, 34(11):1708-1712.
Abstract:
采用SEM和金相仪器对添加不同Y量的纳米粉90W-7Ni-3Fe合金试样断口进行形貌观察和W晶粒测试：并对烧结态试样的相对密度、抗拉强度、延伸率等性能进行测定与分析。结果表明：当Y量在0．2％～0．6％（质量百分数，下同）时，试样相对密度为99.2％～99．6％，抗拉强度为1000MPa-1100MPa，延伸率为16％-19．5％：添加0．4％Y后，W晶粒从原来的20μm～25μm减小到12μm，W晶粒形状由不加稀土时的球形变为近球形或多边形。添加0．4％Y后，在界面上形成了W13．07Ni2.96Fe1.52Y23．65Ox（摩尔数比）的中间相，其阻止了W原子在粘结相中的扩散，阻止了W晶粒长大，细化了W晶粒，提高了合金的性能。
采用SEM和金相仪器对添加不同Y量的纳米粉90W-7Ni-3Fe合金试样断口进行形貌观察和W晶粒测试：并对烧结态试样的相对密度、抗拉强度、延伸率等性能进行测定与分析。结果表明：当Y量在0．2％～0．6％（质量百分数，下同）时，试样相对密度为99.2％～99．6％，抗拉强度为1000MPa-1100MPa，延伸率为16％-19．5％：添加0．4％Y后，W晶粒从原来的20μm～25μm减小到12μm，W晶粒形状由不加稀土时的球形变为近球形或多边形。添加0．4％Y后，在界面上形成了W13．07Ni2.96Fe1.52Y23．65Ox（摩尔数比）的中间相，其阻止了W原子在粘结相中的扩散，阻止了W晶粒长大，细化了W晶粒，提高了合金的性能。
2005, 34(11):1713-1716.
Abstract:
用磁控溅射法在玻璃基片上制备了具有等原子比组成的不同厚度的CoPt薄膜及不同Ag底层厚度的CoPt／Ag薄膜。真空退火后的结果表明，膜厚对CoPt薄膜的微观结构和磁性能有着重要的影响，膜厚较薄时（δ≤15nm）有利于易磁化轴（c轴）垂直于膜面取向，从而具有高的垂直磁各向异性；Ag底层可以诱导L10-CoPt相的形成并使c轴垂直择优取向，且Ag底层越厚其诱导效应越强。
用磁控溅射法在玻璃基片上制备了具有等原子比组成的不同厚度的CoPt薄膜及不同Ag底层厚度的CoPt／Ag薄膜。真空退火后的结果表明，膜厚对CoPt薄膜的微观结构和磁性能有着重要的影响，膜厚较薄时（δ≤15nm）有利于易磁化轴（c轴）垂直于膜面取向，从而具有高的垂直磁各向异性；Ag底层可以诱导L10-CoPt相的形成并使c轴垂直择优取向，且Ag底层越厚其诱导效应越强。
2005, 34(11):1717-1720.
Abstract:
Well-dispersed Silver colloids are prepared from AgNO3 and KBH4 under the protection of polyvinylpyrrolidone (PVP) in the ultrasonic field. The main factors influencing on stability of silver colloids, such as the concentration of PVP and KBH4, ultrasonic time and power, are discussed. The silver colloids are characterized by TEM, SAED and Spectrophotometer. The result indicates that the stable silver nanoparticles are prepared with PVP/ AgNO3 mass ratio of 1:1. Selected area electron diffraction pattern reveals that the silver nanoparticle is of face-centered cubic structure. Spherical-like silver nanoparticles with about 20 nm size are synthesized with AgNO3/ KBH4 molar ratio of 1:2. The dispersion and stability of the silver colloid will be improved after ultrasonic wave treatment. The diameters of silver nanoparticles decrease and the particle size distribution becomes narrow with the ultrasonic power increase. Silver particles with 10~20 nm size and spherical shape have been prepared after 50 min of ultrasonic wave treatment.
Well-dispersed Silver colloids are prepared from AgNO3 and KBH4 under the protection of polyvinylpyrrolidone (PVP) in the ultrasonic field. The main factors influencing on stability of silver colloids, such as the concentration of PVP and KBH4, ultrasonic time and power, are discussed. The silver colloids are characterized by TEM, SAED and Spectrophotometer. The result indicates that the stable silver nanoparticles are prepared with PVP/ AgNO3 mass ratio of 1:1. Selected area electron diffraction pattern reveals that the silver nanoparticle is of face-centered cubic structure. Spherical-like silver nanoparticles with about 20 nm size are synthesized with AgNO3/ KBH4 molar ratio of 1:2. The dispersion and stability of the silver colloid will be improved after ultrasonic wave treatment. The diameters of silver nanoparticles decrease and the particle size distribution becomes narrow with the ultrasonic power increase. Silver particles with 10~20 nm size and spherical shape have been prepared after 50 min of ultrasonic wave treatment.
2005, 34(11):1721-1725.
Abstract:
The effect of alloying elements on the quasi-solid mechanical properties and on the solidification behavior of alloy Al-4.5Cu have been studied in the present paper. The results indicated that Si, Ce, La, Ti and Zr elements can effectively narrow the gap of crystallization range and reduce the hot cracking tendency of Al-4.5Cu, and the addition of La can increase hot crack resistance properties of Al-4.5Cu alloy. A new type of casting Al-4.5Cu alloy has been successfully developed based on the results of the study, which has been used in some areas for its good comprehensive properties at both ambient and elevated temperatures.
The effect of alloying elements on the quasi-solid mechanical properties and on the solidification behavior of alloy Al-4.5Cu have been studied in the present paper. The results indicated that Si, Ce, La, Ti and Zr elements can effectively narrow the gap of crystallization range and reduce the hot cracking tendency of Al-4.5Cu, and the addition of La can increase hot crack resistance properties of Al-4.5Cu alloy. A new type of casting Al-4.5Cu alloy has been successfully developed based on the results of the study, which has been used in some areas for its good comprehensive properties at both ambient and elevated temperatures.
2005, 34(11):1726-1729.
Abstract:
采用普通凝固技术在高镁、低锌和低钇合金中制备出镁合金稳定态准晶相，为制备准晶增强自生复合材料的可行性开辟途径。通过光学显微镜、X—ray衍射、扫描和透射电镜显微分析技术，确定了准晶的组织、相成分及结构。分析了由于合金成分小同，特别是稀土元素Y摩尔分数的不同导致准晶的分布、数量等差异。结果表明：Mg-Zn-Y三元合金在室温冷却过程中，准品相直接从液相形核、长大；伴随Y摩尔分数的增加，准晶相的晶粒度、圆整度和分布均匀化程度均有提高。
采用普通凝固技术在高镁、低锌和低钇合金中制备出镁合金稳定态准晶相，为制备准晶增强自生复合材料的可行性开辟途径。通过光学显微镜、X—ray衍射、扫描和透射电镜显微分析技术，确定了准晶的组织、相成分及结构。分析了由于合金成分小同，特别是稀土元素Y摩尔分数的不同导致准晶的分布、数量等差异。结果表明：Mg-Zn-Y三元合金在室温冷却过程中，准品相直接从液相形核、长大；伴随Y摩尔分数的增加，准晶相的晶粒度、圆整度和分布均匀化程度均有提高。
2005, 34(11):1730-1733.
Abstract:
The role of oxygen in the heat treatment process of SrTiO3 varistor ceramics has been investigated. It is found that the varistor voltage of SrTiO3 ceramics independent of the sample thickness, and it increases with the heat treatment temperatures increase, that the dielectric property is mainly governed by a highly resistive surface layer. The XPS results of Mn 2p and O 1s suggest that the surface layer was formed by oxygen diffusion and surface chemisorption at grain boundaries during the heat treatment in air. The chemisorption of oxygen in grain boundaries, which leads to the highly resistive surface layer, is the origin of the varistor behavior of SrTiO3 ceramics.
The role of oxygen in the heat treatment process of SrTiO3 varistor ceramics has been investigated. It is found that the varistor voltage of SrTiO3 ceramics independent of the sample thickness, and it increases with the heat treatment temperatures increase, that the dielectric property is mainly governed by a highly resistive surface layer. The XPS results of Mn 2p and O 1s suggest that the surface layer was formed by oxygen diffusion and surface chemisorption at grain boundaries during the heat treatment in air. The chemisorption of oxygen in grain boundaries, which leads to the highly resistive surface layer, is the origin of the varistor behavior of SrTiO3 ceramics.
2005, 34(11):1734-1737.
Abstract:
采取溶胶凝胶法在活性炭表面原位合成RuO2·xH2O,经150℃热处理后制成的碳钌复合材料首次应用于碱性电化学电容器中。经电化学测试表明,碳钌电极在碱液中具有良好的容量性质和高功率放电特性,当电流密度为1.0A/g,钌含量为15%(质量分数,下同)的复合材料作为碱性电容的正极,其单电极比容量可达274F/g,是空白活性炭材料的1.22倍,并可较好地抑制电容自放电;该复合材料作为碱性电容的负极,相同电流条件下虽然也具有较高的单电极比容量(278F/g),但电容的自放电现象较为严重。
采取溶胶凝胶法在活性炭表面原位合成RuO2·xH2O,经150℃热处理后制成的碳钌复合材料首次应用于碱性电化学电容器中。经电化学测试表明,碳钌电极在碱液中具有良好的容量性质和高功率放电特性,当电流密度为1.0A/g,钌含量为15%(质量分数,下同)的复合材料作为碱性电容的正极,其单电极比容量可达274F/g,是空白活性炭材料的1.22倍,并可较好地抑制电容自放电;该复合材料作为碱性电容的负极,相同电流条件下虽然也具有较高的单电极比容量(278F/g),但电容的自放电现象较为严重。
2005, 34(11):1743-1746.
Abstract:
研究了用放电等离子烧结技术将WO3和炭黑的混合粉快速原位合成为致密的超细WC块体过程中试样的物相、密度和显微组织的变化，分析了合成过程。结果表明：随着合成温度的升高，碳能快速地将WO3还原成WO2.72，WO2及W，接着发生碳化反应，生成W2C，WC，合成的各阶段相互重叠；当合成温度低于1118℃时，试样的物相发生变化，密度变化不显著，温度继续升高试样发生烧结，且剩余的微量杂相W2C消失，得到致密的WC块体；在合成过程中，试样的显微组织因物相不同而有很大不同，WO3，WO2，W，W2C和WC均呈颗粒状，WO2．72呈棒状，随着温度升高，颗粒由0．2μm长大到0．5μm；WO3还原的前期放出CO2气体，后期放出CO气体，还原反应不经过WO2.9这一中间氧化物阶段。
研究了用放电等离子烧结技术将WO3和炭黑的混合粉快速原位合成为致密的超细WC块体过程中试样的物相、密度和显微组织的变化，分析了合成过程。结果表明：随着合成温度的升高，碳能快速地将WO3还原成WO2.72，WO2及W，接着发生碳化反应，生成W2C，WC，合成的各阶段相互重叠；当合成温度低于1118℃时，试样的物相发生变化，密度变化不显著，温度继续升高试样发生烧结，且剩余的微量杂相W2C消失，得到致密的WC块体；在合成过程中，试样的显微组织因物相不同而有很大不同，WO3，WO2，W，W2C和WC均呈颗粒状，WO2．72呈棒状，随着温度升高，颗粒由0．2μm长大到0．5μm；WO3还原的前期放出CO2气体，后期放出CO气体，还原反应不经过WO2.9这一中间氧化物阶段。
2005, 34(11):1747-1750.
Abstract:
The SnO2:Sb films was prepared on glass substrates by rf magnetron sputtering method. The effect of different doping content and annealing on structure of the thin films were investigated. Result show that the prepared samples are polycrystalline thin films with rutile structure of pure SnO2 and have orientation of (110) direction. The crystallization of the samples changes with the different doping content and annealing conditions. The photoluminescence of the samples was measured at room temperature. For the first time, a UV-violet luminescence peak near 392 nm was observed, and the luminescence mechanism was also tentatively investigated.
The SnO2:Sb films was prepared on glass substrates by rf magnetron sputtering method. The effect of different doping content and annealing on structure of the thin films were investigated. Result show that the prepared samples are polycrystalline thin films with rutile structure of pure SnO2 and have orientation of (110) direction. The crystallization of the samples changes with the different doping content and annealing conditions. The photoluminescence of the samples was measured at room temperature. For the first time, a UV-violet luminescence peak near 392 nm was observed, and the luminescence mechanism was also tentatively investigated.
16 Structure and Properties of Ti-Si-N Nanocomposite Films Prepared by Pulsed-DC Plasma Enhanced CVD
2005, 34(11):1751-1753.
Abstract:
用工业型脉冲直流等离子体增强化学气相沉积技术，在高速钢（W18Cr4V）表面沉积了Ti-Si-N复合薄膜，研究了Ti-Si-N复合薄膜的微观组织和力学性能。结果显示，薄膜相结构为纳米晶TiN和纳米晶或非晶TiSi2以及非晶相Si3N4。在Si含量为5．0at％-28．0at％范围内，薄膜的晶粒尺寸逐渐变大；Ti-Si-N薄膜的显微硬度相对于TiN有明显增加，最高硬度可达40GPa：高温退火后，Ti-Si-N纳米复合薄膜的显微硬度与晶粒尺寸在800℃高温下仍然保持稳定。
用工业型脉冲直流等离子体增强化学气相沉积技术，在高速钢（W18Cr4V）表面沉积了Ti-Si-N复合薄膜，研究了Ti-Si-N复合薄膜的微观组织和力学性能。结果显示，薄膜相结构为纳米晶TiN和纳米晶或非晶TiSi2以及非晶相Si3N4。在Si含量为5．0at％-28．0at％范围内，薄膜的晶粒尺寸逐渐变大；Ti-Si-N薄膜的显微硬度相对于TiN有明显增加，最高硬度可达40GPa：高温退火后，Ti-Si-N纳米复合薄膜的显微硬度与晶粒尺寸在800℃高温下仍然保持稳定。
2005, 34(11):1754-1757.
Abstract:
A sort of new-style dieless drawing process titanium pipe shaped and the method of manufacture technology were introduced. The law of drawing speed was analyzed according to the deformation mechanism of titanium pipe dieless drawing. The mathematical model ofdieless drawing for titanium pipe has been set up, using calculus theory and titanium pipe geometry figure during dieless drawing and so on. It has been proved to true that the mathematical model is very simple, accurate, reliable, and practical through of experiment.
A sort of new-style dieless drawing process titanium pipe shaped and the method of manufacture technology were introduced. The law of drawing speed was analyzed according to the deformation mechanism of titanium pipe dieless drawing. The mathematical model ofdieless drawing for titanium pipe has been set up, using calculus theory and titanium pipe geometry figure during dieless drawing and so on. It has been proved to true that the mathematical model is very simple, accurate, reliable, and practical through of experiment.
2005, 34(11):1758-1761.
Abstract:
以阴阳离子复合掺杂为基础，采用超声共沉淀法、Pechini法和高温固相法合成尖晶石型掺杂锰酸锂前驱体，使用3段热处理方式，即650℃预烧、780℃烧结、550℃回火制备得到掺杂尖晶石LiCo0．05Ni0．05Mn1.9O3．9F0.1。通过化学容量分析测定Mn含量和平均价态，用粒度分布、电镜扫描（SEM）、X射线衍射（XRD）、电化学性能测试对产物进行表征。结果表明产物的Mn含量和平均价态与理论值吻合。3种合成方法相比，超声共沉淀法产物的粒径最窄，比表面积最小（14919cm^2／cm^3），晶型完整，衍射强度最大，结晶性能最佳，晶格常数为0．821nm，晶粒尺寸为57．48nm：经装配电池电化学性能测定，超声共沉淀法产物的比容量更高，循环性能更稳定，经30次循环后容量衰减仅7．2％。
以阴阳离子复合掺杂为基础，采用超声共沉淀法、Pechini法和高温固相法合成尖晶石型掺杂锰酸锂前驱体，使用3段热处理方式，即650℃预烧、780℃烧结、550℃回火制备得到掺杂尖晶石LiCo0．05Ni0．05Mn1.9O3．9F0.1。通过化学容量分析测定Mn含量和平均价态，用粒度分布、电镜扫描（SEM）、X射线衍射（XRD）、电化学性能测试对产物进行表征。结果表明产物的Mn含量和平均价态与理论值吻合。3种合成方法相比，超声共沉淀法产物的粒径最窄，比表面积最小（14919cm^2／cm^3），晶型完整，衍射强度最大，结晶性能最佳，晶格常数为0．821nm，晶粒尺寸为57．48nm：经装配电池电化学性能测定，超声共沉淀法产物的比容量更高，循环性能更稳定，经30次循环后容量衰减仅7．2％。
2005, 34(11):1762-1765.
Abstract:
The present work was to determine the optimum sintering system and properties of the nanometer tetragonal polyerystallihe zirconia green body by the aqueous gel tape casting process. The results show that the microstrueture of the green body is even, the calcining process is accomplished with organic burning out, the separated preheating procedure is diminished. Therefore, the efficiency was remarkably improving and the resources was saved. On the basis of DTA-TG analysis, the proper calcining system was obtained. The green body ofzirconia turned into the high performance films, consisting oftetragonal polycry, stalline zirconia after sintering for 6 h at the temperature of 1773 K.
The present work was to determine the optimum sintering system and properties of the nanometer tetragonal polyerystallihe zirconia green body by the aqueous gel tape casting process. The results show that the microstrueture of the green body is even, the calcining process is accomplished with organic burning out, the separated preheating procedure is diminished. Therefore, the efficiency was remarkably improving and the resources was saved. On the basis of DTA-TG analysis, the proper calcining system was obtained. The green body ofzirconia turned into the high performance films, consisting oftetragonal polycry, stalline zirconia after sintering for 6 h at the temperature of 1773 K.
2005, 34(11):1766-1769.
Abstract:
利用弯曲应力松弛方法研究了魏氏组织Ti-6Al-4V合金200℃．400℃和600℃时的应力松弛行为，并利用TEM研究了应力松弛前后微观组织变化：宏观热力学参数结合微观组织观察初步探讨应力松弛机理。研究表明：应力松弛开始时应力下降较快．随时间延长．应力下降速率降低．最后趋于应力松弛极限。TEM微观组织观察结果结合表现应力指数分析表明：200℃和400℃应力松弛变形机制为位错蠕变，a型位错滑移：而600℃变形机制则为回复蠕变和原子扩散的共同作用机制．a型和a＋c型或c型均开动．产生滑移和攀移。
利用弯曲应力松弛方法研究了魏氏组织Ti-6Al-4V合金200℃．400℃和600℃时的应力松弛行为，并利用TEM研究了应力松弛前后微观组织变化：宏观热力学参数结合微观组织观察初步探讨应力松弛机理。研究表明：应力松弛开始时应力下降较快．随时间延长．应力下降速率降低．最后趋于应力松弛极限。TEM微观组织观察结果结合表现应力指数分析表明：200℃和400℃应力松弛变形机制为位错蠕变，a型位错滑移：而600℃变形机制则为回复蠕变和原子扩散的共同作用机制．a型和a＋c型或c型均开动．产生滑移和攀移。
2005, 34(11):1770-1773.
Abstract:
研究了热处理对超轻Mg-10．02Li-3．86Zn-2．54Al-1．76Cu合金力学性能的影响。研究表明，随淬火温度升高（150℃～350℃），Mg及Al在口相中固溶程度增加，合金淬火硬度增加；350℃，1h淬火后的时效过程中未发现时效硬化现象，而α相及AlLi相从β相中析出将导致合金软化，且时效温度越高，软化速度越快。同时，淬火温度升高至250℃，固溶程度增加导致合金强度增加；淬火温度进一步提高至350℃，一方面由于晶粒长大，另一方面可能淬火后Mg在β相中过饱和度增加，α相易沿β晶界连续析出，导致合金强度及塑性大幅度下降。
研究了热处理对超轻Mg-10．02Li-3．86Zn-2．54Al-1．76Cu合金力学性能的影响。研究表明，随淬火温度升高（150℃～350℃），Mg及Al在口相中固溶程度增加，合金淬火硬度增加；350℃，1h淬火后的时效过程中未发现时效硬化现象，而α相及AlLi相从β相中析出将导致合金软化，且时效温度越高，软化速度越快。同时，淬火温度升高至250℃，固溶程度增加导致合金强度增加；淬火温度进一步提高至350℃，一方面由于晶粒长大，另一方面可能淬火后Mg在β相中过饱和度增加，α相易沿β晶界连续析出，导致合金强度及塑性大幅度下降。
2005, 34(11):1774-1777.
Abstract:
采用电化学线性极化、交流阻抗谱技术研究了不同基片偏压上阴极电弧沉积TiN/Ti镀层在50×10-6g/gCl-溶液中的腐蚀行为,并对镀层腐蚀的机理进行了探讨。结果表明:基片偏压–400V时,镀层耐蚀性能好;镀层表面的针孔是诱发镀层和基材体系发生点蚀、电偶腐蚀的主要缺陷。
采用电化学线性极化、交流阻抗谱技术研究了不同基片偏压上阴极电弧沉积TiN/Ti镀层在50×10-6g/gCl-溶液中的腐蚀行为,并对镀层腐蚀的机理进行了探讨。结果表明:基片偏压–400V时,镀层耐蚀性能好;镀层表面的针孔是诱发镀层和基材体系发生点蚀、电偶腐蚀的主要缺陷。
2005, 34(11):1778-1781.
Abstract:
用脉冲直流等离子体增强化学气相沉积（PCVD）方法在高速钢（HSS）基体上制备了Ti—Si-N薄膜，重点从不同温度退火后薄膜相结构、晶粒尺寸和显微硬度的变化等方面，探讨了不同Si含量的Ti-Si-N薄膜的高温热稳定性。结果表明：Ti-Si-N薄膜在900℃以内退火处理后，晶粒尺寸和显微硬度并无明显突变，尤其是Si含量较低时，在800℃，晶粒尺寸和显微硬度几乎没有变化，表明Ti-Si-N薄膜具有非常良好的高温热稳定性，这可能与薄膜相形成在高温下仍为调幅分解有关。
用脉冲直流等离子体增强化学气相沉积（PCVD）方法在高速钢（HSS）基体上制备了Ti—Si-N薄膜，重点从不同温度退火后薄膜相结构、晶粒尺寸和显微硬度的变化等方面，探讨了不同Si含量的Ti-Si-N薄膜的高温热稳定性。结果表明：Ti-Si-N薄膜在900℃以内退火处理后，晶粒尺寸和显微硬度并无明显突变，尤其是Si含量较低时，在800℃，晶粒尺寸和显微硬度几乎没有变化，表明Ti-Si-N薄膜具有非常良好的高温热稳定性，这可能与薄膜相形成在高温下仍为调幅分解有关。
2005, 34(11):1786-1789.
Abstract:
通过对Au—Ag—Cu—Pt高含金量齿科铸造合金的研究，分析此合金的时效硬化行为，为其临床实际应用提供理论基础。试样经800℃，30min固溶处理后在350℃，500℃进行等温时效，通过金相组织观察、显微硬度测试、X射线衍射（XRD）和扫描电子显微（SEM）分析，研究了此齿科合金时效后的显微结构与性能。结果表明，该合金是典型的时效硬化型合金。长时间时效使面心立方基体α0相发生分解，最终转变为面心立方富银α2无序相和富Cu的面心正方AuCuⅠ有序相。两相以片状存在。晶界周围的片层厚，晶内的片层很薄，两者的分解方式不同。350℃短时间时效析出的AuCuⅠ有序相与基体保持共格，使基体中产生应力场，有效地提高了合金的硬度。
通过对Au—Ag—Cu—Pt高含金量齿科铸造合金的研究，分析此合金的时效硬化行为，为其临床实际应用提供理论基础。试样经800℃，30min固溶处理后在350℃，500℃进行等温时效，通过金相组织观察、显微硬度测试、X射线衍射（XRD）和扫描电子显微（SEM）分析，研究了此齿科合金时效后的显微结构与性能。结果表明，该合金是典型的时效硬化型合金。长时间时效使面心立方基体α0相发生分解，最终转变为面心立方富银α2无序相和富Cu的面心正方AuCuⅠ有序相。两相以片状存在。晶界周围的片层厚，晶内的片层很薄，两者的分解方式不同。350℃短时间时效析出的AuCuⅠ有序相与基体保持共格，使基体中产生应力场，有效地提高了合金的硬度。
2005, 34(11):1790-1793.
Abstract:
利用化学共沉淀、高能球磨技术及热压烧结等方法制备出纳米掺杂Ag（SnFe）O2触头合金，通过X射线衍射（XRD）、透射电镜（TEM）和冷场发射扫描电镜（FESEM）等对合金触头及其燃弧性能进行了分析。结果发现：Fe元素的加入，使Sn02纳米颗粒在550℃以下焙烧制粉和750℃以下块体烧结成型时都未明显长大，保持在20nm左右，制备的触头合金呈现纳米第二相弥散均匀分布在Ag基体中。在模拟电弧侵蚀试验中，该合金电弧阴极斑点铺展在较大区域，形成多点燃弧形貌，有效降低燃弧时间和电弧电流，分散电弧能量，使阴极斑点没有明显的液体喷溅、Ag的蒸发和第二相的分解，同时非晶的纳米第二相与Ag的润湿性更好，可进一步增加熔体粘度，提高耐电弧侵蚀性能。
利用化学共沉淀、高能球磨技术及热压烧结等方法制备出纳米掺杂Ag（SnFe）O2触头合金，通过X射线衍射（XRD）、透射电镜（TEM）和冷场发射扫描电镜（FESEM）等对合金触头及其燃弧性能进行了分析。结果发现：Fe元素的加入，使Sn02纳米颗粒在550℃以下焙烧制粉和750℃以下块体烧结成型时都未明显长大，保持在20nm左右，制备的触头合金呈现纳米第二相弥散均匀分布在Ag基体中。在模拟电弧侵蚀试验中，该合金电弧阴极斑点铺展在较大区域，形成多点燃弧形貌，有效降低燃弧时间和电弧电流，分散电弧能量，使阴极斑点没有明显的液体喷溅、Ag的蒸发和第二相的分解，同时非晶的纳米第二相与Ag的润湿性更好，可进一步增加熔体粘度，提高耐电弧侵蚀性能。
2005, 34(11):1794-1797.
Abstract:
在C／C复合材料表面采用熔浆法制备Mo—Si系涂层的烧结过程中通入氮气，开发了Si3N4．MoSi2／Si—SiC（Mo-Si-N系）多层抗氧化涂层，并初步考察了涂层的抗氧化性能。结果表明，多层涂层的致密性主要受制于起始氮化温度。只有在Si熔点以上通入氮气，才能获得致密无缺陷的涂层。多层涂层的底层为SiC，外层为Si3N4，中间层为MoSi2／Si。这种多层涂层的抗氧化性能与涂层中MoSi2的含量有关；MoSi2含量为30％（体积分数，下同）和40％时，与真空中合成的Mo-Si涂层相比，高温抗氧化性能显著改善，抗氧化温度提高到1400℃～1450℃。
在C／C复合材料表面采用熔浆法制备Mo—Si系涂层的烧结过程中通入氮气，开发了Si3N4．MoSi2／Si—SiC（Mo-Si-N系）多层抗氧化涂层，并初步考察了涂层的抗氧化性能。结果表明，多层涂层的致密性主要受制于起始氮化温度。只有在Si熔点以上通入氮气，才能获得致密无缺陷的涂层。多层涂层的底层为SiC，外层为Si3N4，中间层为MoSi2／Si。这种多层涂层的抗氧化性能与涂层中MoSi2的含量有关；MoSi2含量为30％（体积分数，下同）和40％时，与真空中合成的Mo-Si涂层相比，高温抗氧化性能显著改善，抗氧化温度提高到1400℃～1450℃。
2005, 34(11):1798-1801.
Abstract:
采用水热电化学法成功制备了HA/ZrO2复合涂层,对涂层的组分结构、表面形貌、热稳定性进行了研究,并探讨了ZrO2的复合对涂层结合强度和生物活性的影响.结果表明当温度小于200℃时,得到缺钙磷灰石Ca10-x(HPO4)x(PO4)6-x(OH)2-x(calcium deficient hydroxyapatite,简称CDHA,0≤x≤1)和ZrO2的复合涂层,温度在200℃时,得到HA/ZrO2复合涂层;经焙烧处理后,涂层中四方晶相ZrO2(t-ZrO2)与单斜晶相ZrO2(m-ZrO2)之间发生马氏体相变;800℃焙烧后,HA部分分解为β-Ca3(PO4)2(β-TCP);当涂层中ZrO2小于35.22%(质量分数,下同)时,HA/ZrO2复合涂层的结合强度明显高于纯HA涂层;复合涂层在模拟体液中浸泡7 d后,表面即形成一层碳磷灰石层,ZrO2的复合没有降低涂层的生物活性.
采用水热电化学法成功制备了HA/ZrO2复合涂层,对涂层的组分结构、表面形貌、热稳定性进行了研究,并探讨了ZrO2的复合对涂层结合强度和生物活性的影响.结果表明当温度小于200℃时,得到缺钙磷灰石Ca10-x(HPO4)x(PO4)6-x(OH)2-x(calcium deficient hydroxyapatite,简称CDHA,0≤x≤1)和ZrO2的复合涂层,温度在200℃时,得到HA/ZrO2复合涂层;经焙烧处理后,涂层中四方晶相ZrO2(t-ZrO2)与单斜晶相ZrO2(m-ZrO2)之间发生马氏体相变;800℃焙烧后,HA部分分解为β-Ca3(PO4)2(β-TCP);当涂层中ZrO2小于35.22%(质量分数,下同)时,HA/ZrO2复合涂层的结合强度明显高于纯HA涂层;复合涂层在模拟体液中浸泡7 d后,表面即形成一层碳磷灰石层,ZrO2的复合没有降低涂层的生物活性.
2005, 34(11):1802-1805.
Abstract:
采用CoCrPtNb四元合金作磁记录介质，并采用多层膜结构（CoCrPt）100-Nbx/CrTi／C／Glass制备玻璃盘基硬盘。实验结果表明：采用适宜厚度的籽晶层与合适组分的底层和磁性层的多层膜结构，即使在室温下溅射，此种薄膜磁记录介质也可得到高达260kA／m的矫顽力；在550℃高温下，经过30min真空退火后，其矫顽力有较大幅度提高，并在Nb含量为2．4％（原子分数）时达到极大值386kA／m，适用于高密度磁记录。同时，也详细分析了磁性层和底层组分、籽晶层厚度以及真空退火对磁记录介质磁性能和微结构的影响。
采用CoCrPtNb四元合金作磁记录介质，并采用多层膜结构（CoCrPt）100-Nbx/CrTi／C／Glass制备玻璃盘基硬盘。实验结果表明：采用适宜厚度的籽晶层与合适组分的底层和磁性层的多层膜结构，即使在室温下溅射，此种薄膜磁记录介质也可得到高达260kA／m的矫顽力；在550℃高温下，经过30min真空退火后，其矫顽力有较大幅度提高，并在Nb含量为2．4％（原子分数）时达到极大值386kA／m，适用于高密度磁记录。同时，也详细分析了磁性层和底层组分、籽晶层厚度以及真空退火对磁记录介质磁性能和微结构的影响。
2005, 34(11):1806-1809.
Abstract:
The erosion of tungsten electrode in GTA (Tungsten-inert-Gas Arc) welding under the protection of argon with a little of oxygen contamination have been investigated. Results show that the erosion of tungsten increases greatly if a little of oxygen is add in argon gas because tungsten on the surface of electrode reacts with oxygen to form tungsten oxide. Melting and evaporation of thoria were the major reasons for the erosion of thoria in electrode. To ensure the purity grade and flow rate of shielding inert gas, to use tungsten electrode activated with nanosized thoria are two better ways to decrease the erosion rate of electrode.
The erosion of tungsten electrode in GTA (Tungsten-inert-Gas Arc) welding under the protection of argon with a little of oxygen contamination have been investigated. Results show that the erosion of tungsten increases greatly if a little of oxygen is add in argon gas because tungsten on the surface of electrode reacts with oxygen to form tungsten oxide. Melting and evaporation of thoria were the major reasons for the erosion of thoria in electrode. To ensure the purity grade and flow rate of shielding inert gas, to use tungsten electrode activated with nanosized thoria are two better ways to decrease the erosion rate of electrode.
Jiang Jun
,
Jiang Bingyao
,
Ren Congxin
,
Zhang Fumin
,
Feng Tao
,
Wang Xi
,
Liu Xianghuai
,
Zou Shichang
2005, 34(11):1810-1813.
Abstract:
Platinum was deposited onto molybdenum grid by ion beam assisted deposition (IBAD). Electron emission behavior from molybdenum grids with and without Platinum contaminated by active electron emission substances (Ba, BaO) of the cathode were measured using analogous diode method. The characteristics on molybdenum grid coated with platinum film were analyzed by X-ray diffraction (XRD), energy dispersive X-ray (EDX) and X-ray photoelectron spectroscopy (XPS). The results show that the electron emission from the grid coated with platinum film is less than that without Platinum film, and the mechanism for suppression of the electron emission of molybdenum grid coated with Platinum film was discussed.
Platinum was deposited onto molybdenum grid by ion beam assisted deposition (IBAD). Electron emission behavior from molybdenum grids with and without Platinum contaminated by active electron emission substances (Ba, BaO) of the cathode were measured using analogous diode method. The characteristics on molybdenum grid coated with platinum film were analyzed by X-ray diffraction (XRD), energy dispersive X-ray (EDX) and X-ray photoelectron spectroscopy (XPS). The results show that the electron emission from the grid coated with platinum film is less than that without Platinum film, and the mechanism for suppression of the electron emission of molybdenum grid coated with Platinum film was discussed.
2005, 34(11):1814-1817.
Abstract:
La0.5Sr0.5MnO3 nano crystalline was synthesized by sol-gel auto-combustion method using citric acid as the chelating agents. Some analysis methods, which consisted of FT-IR, XRD, DSC-TG, wave-guide, were used to character the gel and the products after calcining. It was shown that metal ions and carboxyl were coordinated by the orientated manner. The phenomenon of melt, combustion and forming crystal for gel were observed in the process of thermo-decomposition, the nano crystalline had a dielectric loss in the frequency range of measurement. With the increasing of thickness, the reflectivity of perovskite-type nano crystalline increased and absorption peak shifted from high frequency to low frequency.
La0.5Sr0.5MnO3 nano crystalline was synthesized by sol-gel auto-combustion method using citric acid as the chelating agents. Some analysis methods, which consisted of FT-IR, XRD, DSC-TG, wave-guide, were used to character the gel and the products after calcining. It was shown that metal ions and carboxyl were coordinated by the orientated manner. The phenomenon of melt, combustion and forming crystal for gel were observed in the process of thermo-decomposition, the nano crystalline had a dielectric loss in the frequency range of measurement. With the increasing of thickness, the reflectivity of perovskite-type nano crystalline increased and absorption peak shifted from high frequency to low frequency.
2005, 34(11):1818-1822.
Abstract:
采用TiB2-Al2O3-Al还原体系，通过燃烧还原技术制备了TiB2-Al2O3陶瓷复合粉体。利用XRD，XPS和SEM技术对合成粉体的相组成、化学组成及宏观组织结构进行了分析。复合粉的显微结构由TEM和HREM进行表征。结果表明，用燃烧合成法在420℃～700℃之间可制得TiB2-Al2O3陶瓷复合粉体。该粉体仅由TiB2和Al2O3两相组成，颗粒分布较均匀。由于TiB2与Al2O3间形成了结合良好的界面，颗粒间彼此能有效地抑制晶粒长大，从而使TlB2-Al2O3陶瓷复合粉的粒径减小，颗粒平均粒度在3μm～5μm之间。
采用TiB2-Al2O3-Al还原体系，通过燃烧还原技术制备了TiB2-Al2O3陶瓷复合粉体。利用XRD，XPS和SEM技术对合成粉体的相组成、化学组成及宏观组织结构进行了分析。复合粉的显微结构由TEM和HREM进行表征。结果表明，用燃烧合成法在420℃～700℃之间可制得TiB2-Al2O3陶瓷复合粉体。该粉体仅由TiB2和Al2O3两相组成，颗粒分布较均匀。由于TiB2与Al2O3间形成了结合良好的界面，颗粒间彼此能有效地抑制晶粒长大，从而使TlB2-Al2O3陶瓷复合粉的粒径减小，颗粒平均粒度在3μm～5μm之间。
2005, 34(11):1827-1829.
Abstract:
The mechanical properties of molybdenum with 3wt% niobium single crystal materials (Mo-3Nb single crystal material) were tested by miniature disk testing method. It is found that the yield stress, the fracture strength and the micro-hardness of Mo-3Nb single crystal materials by Russian supplying were higher than those of the home-made ones, while the elongations of the former material were lower than the later material. However, according to the TEM morphologies, Nb component in Russian supplying materials was a little more than that in the home-made single crystal materials, and some bar-type strengthening phases were observed in Russian supplying materials. Therefore, the difference of the microstructures and the component may cause the mechanical properties difference of the two materials.
The mechanical properties of molybdenum with 3wt% niobium single crystal materials (Mo-3Nb single crystal material) were tested by miniature disk testing method. It is found that the yield stress, the fracture strength and the micro-hardness of Mo-3Nb single crystal materials by Russian supplying were higher than those of the home-made ones, while the elongations of the former material were lower than the later material. However, according to the TEM morphologies, Nb component in Russian supplying materials was a little more than that in the home-made single crystal materials, and some bar-type strengthening phases were observed in Russian supplying materials. Therefore, the difference of the microstructures and the component may cause the mechanical properties difference of the two materials.
2005, 34(11):1830-1834.
Abstract:
合成了N-正丁基异辛酰胺(BiOA),并对其从盐酸介质中萃取Pt(IV)进行了研究。结果表明:待萃液Pt(IV)浓度为1.000g·L-1,HCl浓度为5mol·L-1时,用2.0mol·L-1N-正丁基异辛酰胺-5%TBP-正辛烷按相比(O/A)1:1混合萃取Pt(IV),经过5min的萃取振荡,萃取率可达99.5%。此萃取体系中TBP对Pt(IV)无协萃效应;水是载Pt(IV)有机相的有效反萃剂,反萃率可以达到90.3%。N-正丁基异辛酰胺萃取Pt(IV)的反应是放热反应,反应热为–10.52kJ·mol-1。红外光谱分析表明,在1mol·L-1~5mol·L-1的HCl范围内,N-正丁基异辛酰胺萃取铂的反应为酸性离子缔合萃取。萃取反应为:PtCl62-+2BiOA(0)+2H+→[(BiOAH+)2·PtCl62-](0)。
合成了N-正丁基异辛酰胺(BiOA),并对其从盐酸介质中萃取Pt(IV)进行了研究。结果表明:待萃液Pt(IV)浓度为1.000g·L-1,HCl浓度为5mol·L-1时,用2.0mol·L-1N-正丁基异辛酰胺-5%TBP-正辛烷按相比(O/A)1:1混合萃取Pt(IV),经过5min的萃取振荡,萃取率可达99.5%。此萃取体系中TBP对Pt(IV)无协萃效应;水是载Pt(IV)有机相的有效反萃剂,反萃率可以达到90.3%。N-正丁基异辛酰胺萃取Pt(IV)的反应是放热反应,反应热为–10.52kJ·mol-1。红外光谱分析表明,在1mol·L-1~5mol·L-1的HCl范围内,N-正丁基异辛酰胺萃取铂的反应为酸性离子缔合萃取。萃取反应为:PtCl62-+2BiOA(0)+2H+→[(BiOAH+)2·PtCl62-](0)。
2005, 34(11):1835-1838.
Abstract:
利用微弧氧化技术，通过增加涂层致密性的方法及选择合适的放电电压，在钛合金表面制备出致密的、与基体结合优良的微弧氧化膜。微弧氧化膜分为3层：过渡层、致密层和疏松层。XRD分析表明，微弧氧化膜主要由Al2TiO5和Al2SiO5组成。在700℃循环氧化100h后，经微弧氧化处理的钛合金的氧化增重量为2．08mg／cm^2，低于未经微弧氧化处理的钛合金的增重量（20mg／cm^2），因而微弧氧化能有效地提高钛合金的抗高温氧化性能。
利用微弧氧化技术，通过增加涂层致密性的方法及选择合适的放电电压，在钛合金表面制备出致密的、与基体结合优良的微弧氧化膜。微弧氧化膜分为3层：过渡层、致密层和疏松层。XRD分析表明，微弧氧化膜主要由Al2TiO5和Al2SiO5组成。在700℃循环氧化100h后，经微弧氧化处理的钛合金的氧化增重量为2．08mg／cm^2，低于未经微弧氧化处理的钛合金的增重量（20mg／cm^2），因而微弧氧化能有效地提高钛合金的抗高温氧化性能。
2005, 34(11):1839-1841.
Abstract:
采用浸渍还原法(I-R法)在Nafion离子膜上镀覆纳米Ag,并就AgNO3浓度对SPE电极镀覆纳米银的影响作了研究.研究表明采用I-R法可制得细致Ag镀层,有效增加Ag的分散度及电极的真实面积.在还原剂浓度为0.1mol·L-1,浸渍还原温度均为50℃及浸渍还原时间分别为40 min,60 min的条件下,调节浸渍液AgNO3浓度至3.5 mmol·L-1时,可获得致密、均匀的纳米级Ag/SPE电极.同时验证砂纸糙化的预处理有利于增加Ag的负载和附着力,有利于提高Ag催化层的有效面积.
采用浸渍还原法(I-R法)在Nafion离子膜上镀覆纳米Ag,并就AgNO3浓度对SPE电极镀覆纳米银的影响作了研究.研究表明采用I-R法可制得细致Ag镀层,有效增加Ag的分散度及电极的真实面积.在还原剂浓度为0.1mol·L-1,浸渍还原温度均为50℃及浸渍还原时间分别为40 min,60 min的条件下,调节浸渍液AgNO3浓度至3.5 mmol·L-1时,可获得致密、均匀的纳米级Ag/SPE电极.同时验证砂纸糙化的预处理有利于增加Ag的负载和附着力,有利于提高Ag催化层的有效面积.
2005, 34(11):1842-1845.
Abstract:
对在纳米压入仪上进行悬臂梁法测量弹性模量的主要影响因素进行了综合分析,主要包括加载系统悬置弹簧刚度、压头压入、梁沿截面宽度方向挠曲、梁支座附加挠曲等影响。在考虑这些因素的基础上,得到了悬臂梁的有效挠度,利用有效挠度与载荷之间的关系,评价悬臂梁材料的弹性模量。对单晶硅(100)悬臂梁试样进行了实验,得到其弹性模量为155GPa±9.5%GPa,与参考文献值符合较好。表明在纳米压入仪上进行悬臂梁法测量,只有综合这些影响因素后,才能获得有效、准确的弹性模量测量结果。
对在纳米压入仪上进行悬臂梁法测量弹性模量的主要影响因素进行了综合分析,主要包括加载系统悬置弹簧刚度、压头压入、梁沿截面宽度方向挠曲、梁支座附加挠曲等影响。在考虑这些因素的基础上,得到了悬臂梁的有效挠度,利用有效挠度与载荷之间的关系,评价悬臂梁材料的弹性模量。对单晶硅(100)悬臂梁试样进行了实验,得到其弹性模量为155GPa±9.5%GPa,与参考文献值符合较好。表明在纳米压入仪上进行悬臂梁法测量,只有综合这些影响因素后,才能获得有效、准确的弹性模量测量结果。
2005, 34(11):1846-1848.
Abstract:
在1.0 mol·L-1～2.0 mol·L-1的H2SO4介质中,Ce(Ⅳ)与DBC-偶氮氯膦反应产生褪色反应,测定铈表观摩尔吸光系数为ε530nm=4.89×104L·mol-1·crm-1,Ce(IV)浓度范围在0.020μg·mL-1～0.88μg·mL-1范围内遵守比耳定律.考察了24种共存离子对测定铈的影响.本方法已满意地用于测定分子筛中的铈.
在1.0 mol·L-1～2.0 mol·L-1的H2SO4介质中,Ce(Ⅳ)与DBC-偶氮氯膦反应产生褪色反应,测定铈表观摩尔吸光系数为ε530nm=4.89×104L·mol-1·crm-1,Ce(IV)浓度范围在0.020μg·mL-1～0.88μg·mL-1范围内遵守比耳定律.考察了24种共存离子对测定铈的影响.本方法已满意地用于测定分子筛中的铈.
