Al效应对LaNi5-xAlx系合金贮氢性能的影响

测定了LaNi5-xAlx(x=0，0．1，0．2，0．3)系合金在吸放氢过程中的贮氢性能。结果表明，贮氢容量随合金中Al含量的增加而降低，平台压力和热力学焓变和熵变随合金中Al含量的增加而降低，合金形成氢化物的稳定性增强；LaNi5-xAlx系合金在吸放氢过程中的平台压力存在一定的差异，即滞后现象，滞后系数随合金中Al含量的增加而降低，这是LaNi5-xAlx系的晶胞体积随合金中Al含量的增加而增加的必然结果;LaNi5-xAlx系合金的吸放氢动力学参数也与合金中的Al含量有关，活化能随Al含量的增加而降低，但活化能不存在数量级的差异。     

镶牙换代钛金牙

分别以Miedema坐标、合金自扩散激活能ΔHs与形成焓ΔHf为参数坐标，将多元合金分解为若干相应的二元合金叠加，对有实验结果的128个二元和153个多元机械合金化(MA)非晶合金的形成规律进行了研究。结果：以上2种坐标中，分别可由一直线或曲线将非晶形成与非形成区分割，方程为：Miedema坐标，二元系，y=2．8600x 0．22；多元系，y=2．7900x 0．27，总区分率均为80％：ΔHs～ΔHf坐标，二元系，y=0．0005x^2 0．20x-23；多元系，y=0．0005x^ 0．21x-25，总区分率分别为85％和83％。合金包含过渡族金属、涵盖非过渡族金属及类金属，并扩展至多元系，同时与已有定性以及半定量结果进行了比较。     

非化学计量比混合稀土—镍系贮氢合金的研究

本文研究了非化学计量比混合稀土－镍系贮氢合金ＭｍＢｘ的配比数ｘ对合金结构、热力学性能和金属氢化物（ＭＨ）电极充放电发性能的影响。随着配比数ｘ的减小，合金晶胞体积和金属氢化物生成焓（－ΔＨ）增加，平台压力降低且与配比ｘ有ｌｎｐｅｑ＝１．９９ｘ－１１．１３的关系。当ｘ〈５．０时，合金在ＣａＣｕ５型主相之外析出Ｃｅ２Ｎｉ７第二相，该第二相具有较高的电催化活性。ｘ〈５．０时，合金电极具有较高的初容量和活化     

Al—Si系合金（3）

3.3 Al-Si-Mg系合金的组织与机械性能此系中JIS实用合金有AC4A、AC4C和AC4CH。它们都是铸造性能良好的Al-Si合金中添加了少量的Mg,由于Mg_2Si中间相析出的热处理效果提高了强度。Mg量略微多一点的AC4C具有高的强度、良好的铸造性和耐蚀性。为了防止Fe的坏影响,通常加入Fe量的50～80％的Mn。在此系合金中,多使用较纯的Al-Si-Mg系AC4C(AA356)和Fe含量控制在0.20％以下提高韧性的AC全CH(AAA356),但后者大量用作汽车轮子。在铸件用的合金中,它们虽属中等强度的,但延伸率高、韧性     

Al—Si系合金（4）

4 变形材料合金的组织与性能 Al-Si系变形铝合金的用途,主要是做锻件、接合件和建筑材料。本节叙述这些用途,以及说明合金的有关组织和性能; 4.1 锻造用合金表3示出按Si量和锻造温度区分的锻造合金及用途。多用于制造各种活塞、VTR缸等。过共晶系合金着重用于要求耐磨性     

Tb—Dy—Fe—M四元系超磁致伸缩材料的磁性

研究了Ｔｂ０．２７Ｄｙ０．７３Ｆｅｘ（ｘ＝１．８，１．９，２，２．１）三元系和Ｔｂ０．２７Ｄｙ０．７３Ｆｅ１．８Ｍ０．１（Ｍ＝Ｚｎ，Ｔｉ，Ａｌ，Ｃｒ）四元系超磁致伸缩材料的磁性。合金在氩气保护的真空电弧炉中熔炼，铸锭在１０００℃真空热处理７天，用法拉第磁秤测定居里温度，用ＬＤＪ９５００振动样品磁强计测磁化曲线，用电阻应变计测量磁致伸缩。Ｔｂ０．２７Ｄｙ０．７３Ｆｅｘ合金的居里温度在３５５～３７５℃范围内，加入Ｚｎ、Ｔｉ、Ａｌ和Ｃｒ降低合金的居里温度，加Ｃｒ增加合金的磁致伸缩，加Ａｌ增加合金在低磁场下的磁致伸缩，加Ｚｎ，Ｔｉ降低磁致伸缩。除加Ｃｒ外，热处理也能提高合金的磁致伸缩。     

TiC/Al和SiC/Al中间合金对Mg-Al系合金晶粒的细化

研制出两种新型的Mg-Al系合金晶粒细化剂——Al-4％TiC和Al-10％SiC中间合金。结果表明：这两种中间合金对Mg-Al系合金均有良好的晶粒细化作用。向AZ63合金中加入1％的TiC／Al中间合金可使其晶粒由原来的约2mm减小至250μm左右；向AZ31合金中加入0．5％的SiC／Al中间合金可使其晶粒由原来的约600μm减小至200μm左右。分析认为，表面覆有Al4C3过渡层的TiC和SiC颗粒可以作为α-Mg的结晶核心，同时SiC颗粒本身也可以作为α-Mg的异质结晶核心。大量异质结晶核心的存在是导致α-Mg晶粒细化的主要原因。     

钛系多元储氢合金的研究

本文对钛系多组元储氢合金进行了开发研究,发现Ti-Zr-Mn-V-Cr系具有满意的性能。该合金容易活化,吸放氢速度快,储氢量大,释氢量可达195ml/g以上。P-C-T曲线表明,该合金的平台特性好,平台压力适中,工作性能稳定,比现有Ti系典型合金TiFe优越。     

Zr－Nb系合金耐蚀性能研究

结合核动力堆用燃料包壳对锆合金耐蚀性能的要求，大范围考察了Ｎｂ含量为０．５％，１．０％，２．６％（ｗｔ％）的Ｚｒ—Ｎｂ二元合金及含Ｃｒ、Ｍｏ、Ｓｎ、Ｂｉ、Ｆｅ、Ｃｅ和Ｓｉ的Ｚｒ－１Ｎｂ及多元合金，共１７种成分的Ｚｒ－Ｎｂ系合金在４００℃，１０．３ＭＰａ水蒸汽中的长期腐蚀规律（达１８２天）。在腐蚀转折前，Ｚｒ－Ｎｂ系合金的腐蚀动力学曲线均近似于抛物线规律，而在转折之后存在与线性规律偏离现象。长期腐蚀增重的分析说明：通过合理的多元合金化，即增加或降低Ｎｂ含量，并主加Ｆｅ、Ｂｉ、Ｓｎ和Ｎｉ而辅加少量的Ｃｒ、Ｍｏ、Ｔｅ和Ｓｉ，Ｚｒ－１Ｎｂ合金的耐蚀性大有潜力可挖。     

ZL210A高强度铸造铝合金的研制

研制了一种新型的Ａｌ－Ｃｕ系高强度铸造合金材料。通过对合金元素及含量的优化设计、晶粒细化剂、ＳＭＴ熔炼工艺和热处理工艺等方面的研究，使合金获得优良的机械性能（σｂ＝４００￣５００ＭＰａ，δ＝３％￣６％）。新合金放宽了对Ｆｅ，Ｓｉ有害杂质的限量，具有很高的经济价值和使用价值。     

A density-based fuzzy clustering technique for non-destructive detection of defects in materials

In non-destructive testing and evaluation of materials, defects contain visible aggregations of similar levels of brightness with large scale of correlation between them. In most cases, these brightnesses have no notable contrast relative to non-defect counterparts. However, the density and the size of the defect are visually the most notable features. In this paper, we have utilized human conception for classifying defects by the fusion of fuzzy clustering method and fuzzy logic rules based on the density and the size of the defect. The probability of detection and the probability of error are compared with the Bayes classifier. The proposed approach shows that there is less dependency between the variation of density and size of a defect and variations of noise density and distribution. Experimental images from eddy current, ultrasonic and radiography techniques are investigated. It is shown that the new approach reduces the noise and drift, leading to a better detection of defects.     

带钢退火关键工艺与产品质量综合控制技术概述

冷轧带钢退火方式有连续退火与罩式退火两种,分析了带钢连续退火与罩式退火生产中的主要技术难题,介绍了在冷轧带钢退火工序所取得的技术成果。首先,从连退机组带钢跑偏、瓢曲与板形方面提出了跑偏因子,瓢曲指数,炉内单元内、外板形等参数,简述了相应的表征模型与预报技术;随后,从连退机组炉内张力与炉辊辊形方面简述了连续退火过程以稳定通板与质量控制为目标的连退炉内张力、炉辊辊形优化技术;最后,以治理罩退机组钢卷粘结为目标,从钢卷装炉角度简述了罩退过程装炉优化技术。在此基础上,叙述了该技术成果实施效果与现场应用情况,典型带钢产品的跑偏与瓢曲缺陷发生率控制在0.3%以内,板形改判率控制在0.08%以内;罩退钢卷产品的粘结发生率控制在0.1%以内,实现了对连退机组的跑偏、瓢曲以及板形缺陷与罩退机组的钢卷粘结缺陷的有效治理,大大提高了退火产品质量,保证了退火工序的稳定生产,提升了产品市场竞争力。     

定、转子冲片级进模维护要领及常见故障的排除

通过对电机定、转子片级进冲模结构形式的分类、凸模、凹模常见的固定方式的介绍，阐述了电机定、转子片级进冲模模具在日常使用中的维护和保养要领。重点介绍了凸模、凹模的更换程序，卸料板的安装程序，以及模具在使用中常见故障原因的分析和排除方法。     

DYNAMIC COMPACTION OF PURE COPPER POWDER USING PULSED MAGNETIC FORCE

The compaction of pure Cu powder was carried out through a series of experiments using dynamic magnetic pulse compaction, and the effects of process parameters, such as discharge energy and compacting direction, on the homogeneity and the compaction density of compacted specimens were presented and discussed. The results indicated that the compaction density of specimens increased with the augment of discharge voltage and time. During unidirectional compaction, there was a density gradient along the loading direction in the compacted specimen, and the minimum compaction density was localized to the center of the bottom of the specimen. The larger the aspect ratio of a powder body, the higher the compaction density of the compacted specimen. And high conductivity drivers were beneficial to the increase of the compaction density. The iterative and the double direction compaction were efficient means to manufacture the homogeneous and high-density powder parts.     

Ni60合金粉末炉内重熔工艺及耐磨性研究

目的 获得45钢表面重熔Ni60粉末的最佳重熔工艺,以期提高涂层的耐磨性能.方法 在Ni60合金粉末中加入A型、B型两种胶,滴入适量酒精,制作Ni60预制涂层;采用预粘接法+炉内重熔二步法工艺,在45钢表面重熔镍基合金涂层,通过金相组织实验、显微硬度实验,分别研究重熔温度对所得试样基体至涂层组织形貌和显微硬度的影响,讨论温度对所获试样基体至涂层组织与耐磨性的影响.结果 重熔温度达到1000℃、1100℃时,基体与涂层形成机械咬合的组织形态;1200℃时,基体与涂层形成机械咬合与冶金结合相结合的组织形态,涂层中硬化相数量增多,大小、分布均匀,缺陷最少.1100℃重熔所得涂层的平均显微硬度最高,达到496 HV;1200℃重熔所得试样分界线处的平均显微硬度最好,达到389.7HV,且该温度下所得试样的硬度曲线分布最有规律.结论 45钢基体表面重熔Ni60合金粉末,重熔温度为1200℃时,可有效改善涂层与基体的结合方式,获得机械结合与冶金结合的组织形态;此温度下,涂层组织均匀、细密,试样硬度分布有规律、波动不大,耐磨性最好.     

TiN及TiSiN涂层在海水环境下的摩擦学行为研究

目的对比研究海水环境下Ti N及Ti Si N涂层与Al2O3对磨的摩擦磨损行为。方法采用多弧离子镀技术在316L不锈钢及单晶硅片上制备Ti N及Ti Si N涂层。利用场发射扫描电子显微镜(SEM)、X射线衍射仪(XRD)及X射线光电子能谱仪(XPS)分析了涂层的截面形貌及化学组织成分。选择纳米压痕仪测量了Ti N及Ti Si N涂层的硬度及弹性模量,使用UMT-3往复式摩擦试验机研究了人工模拟海水环境下Al2O3与Ti N及Ti Si N涂层对磨后的摩擦磨损行为,并采用扫描电镜(SEM)、电子能谱(EDS)及表面轮廓仪来深入分析了磨痕的摩擦磨损情况。结果研究表明,Ti N涂层的硬度为32.5 GPa,当Si元素掺入涂层以后,Ti Si N涂层的硬度提高到了37 GPa。同时,较之于Ti N涂层,Ti Si N涂层的腐蚀电流密度下降了一个数量级。在摩擦实验中,Ti N涂层的摩擦系数和磨损率分别为0.35和5.21×10-6 mm3/(N·m),而Ti Si N涂层的摩擦系数和磨损率均有明显下降,分别为0.24和1.96×10-6 mm3/(N·m)。结论 Si元素掺杂后能显著提高Ti N涂层在海水环境下的摩擦学性能,主要归因于结构的致密,硬度、韧性、抗腐蚀性的提高及润滑相的形成。     

Optimization of arc welding processes using a neural network

X-ray and neutron diffractometric methods are described for the early-stage diagnosis of materials. A comparison is made between traditional and innovative technologies, which aim at being included amongst the NDT methods usable on-site. Emphasis is also placed on the gradual removal from instruments of structural restraints, with a tendency towards anthropomorphic functionalities and flexibility. Prototype production and conceptual schemes are presented and discussed. Conceptual tests, applications and case studies are shown as per the state of the art. Particular reference is made to results obtained from data collected from materials containing welding (e.g. titanium alloys, P22, T92 and P92 steel) and micro- and nano-structural alterations (e.g. ceramics, glass and other materials). These results indicate the meaning and usefulness of the early observation of effects induced in the reticolum of metals by loads, residual stress and structural micro/nano variations. It follows that reticular measurements and the diffractometric methods related to them are onlythose currently available to obtain appropriate early-stage diagnosis. A discussion is provided of photonic (X-ray) and neutronic diffraction with corresponding limits and advantages. The hypothesis of creating a new mobile diagnostic device intended for the application of neutron diffraction is introduced.     

Assessment of vitrified CBN wheels for precision grinding

Methods of measuring topographical features of grinding wheels are reviewed. Each technique has advantages and limitations for resolution, measuring depth, ease of application, data analysis and interpretation. Results obtained vary according to the method and instrument employed. Advantages and difficulties experienced with different techniques are discussed. Different replication techniques and materials are compared and suggestions made. A set of parameters that describe the wheel and grain characteristics is defined. Experimental studies with grinding wheels having different structures are carried out in terms of observations and measurements of changes in wheel topography. Experimental results are analysed and discussed in relation to theoretical understanding of abrasive wear and loading.     

Study of colored anodized aluminum with calcon in sulfuric acidic solution using cyclic voltammetry and impedance measurement methods

The effect of coloring condition of Al with Calcon (sodium 2,2'‐dihydroxy‐azonaphthalene‐4‐sulfonate), on the corrosion resistance of Al in 0.1 M sulfuric acid solution was studied, using cyclic voltammetry and measurement of impedance noise methods. The changes in the corrosion resistance of colored aluminum electrodes were evaluated by measuring the magnitude of impedance and cyclic voltammetric responses of anodized and colored electrodes. An irreversible corrosion response was observed at the cyclic voltammogram of the colored aluminum electrode. The current and threshold potential of corrosion responses strongly depends on the applied conditions during anodizing, coloring and sealing stages. In addition, significant changes in impedance at the ac voltammogram and noise level at some ac frequencies were observed, when the electrodes were colored under various conditions. In this regard, the surface of the electrode was studied by Scanning Electron Microscopy (SEM). Comparison of SEM images of the colored and uncolored aluminum specimens showed that the colored surface contained a significant numbers of pits. The results indicated that coloring aluminum with Calcon could reduce corrosion resistance of aluminum and increase roughness of the oxide film.     

空间基础零部件超精密抛光技术研究进展

轴承、齿轮、陀螺仪谐振子、反射镜等是实现航天器旋转支撑、动力传递、姿态控制、空间探测等功能的核心基础零部件,直接影响航天器的性能、寿命和可靠性。为了确保航天任务顺利进行,空间基础零部件必须拥有优异的使役性能、高的可靠性和长的寿命,其工作面的状态是关键影响因素。为此,基于制造角度,必须不断提高工作面的精度和表面质量。然而,空间基础零部件的工作面多为复杂曲面,且材料包含多种元素和金相组织,可控抛光难度大。从轴承、齿轮、陀螺仪谐振子、反射镜等4种空间基础零部件的特点出发,简要陈述了各自的超精密抛光需求及必要性,分类总结了现有的超精密抛光技术,如应用于轴承的双盘研磨抛光、电化学机械抛光、流变抛光,应用于齿轮的磨粒流抛光、流变抛光、电化学机械抛光,应用于陀螺仪谐振子的流变抛光、飞秒激光和离子束质量调平,以及应用于反射镜的磁流变抛光、计算机控制光学表面成型、气囊抛光、离子束修形抛光等,阐述了各种抛光技术的原理和效果,最后展望了超精密抛光技术的发展方向,以期为空间基础零部件的超精密加工提供借鉴。