高强度Pd-Ag-Cu合金电刷材料

在Ｐｄ － Ａｇ － Ｃｕ 合金中添加０－５ ～２ ｗｔ％ 的Ｐｔ, ０－５ ～５ ｗｔ％ 的Ｍｎ , ０－５ ～１０ ｗｔ％ 的Ｎｉ, ０－０１ ～０－５ ｗｔ％ 的Ｓｍ , 研制出２ 种用于玻璃釉电位器的电刷材料Ｐｄ － Ａｇ － Ｃｕ － Ｍｅ１ 和Ｐｄ － Ａｇ － Ｃｕ － Ｍｅ２ 合金。分析２ 种钯基合金材料的物理性能, 加工硬化、时效特性和组织结构, 结果表明, 添加微量Ｓｍ 能有效改善材料的耐磨性能。与进口材料ＴＹ－ ７０ 和美国Ｊ． Ｍ． ＭＥＹ 公司的专利高强度合金Ｐａｌｌｉｎｅｙ － ７ 合金等弹性电刷合金相比, 上述钯基合金材料具有更高的强度和硬度, 可替代ＴＹ－ ７０ 和Ｐａｌｌｉｎｅｙ － ７ 合金用于电刷和弹性滑动触点     

透氢用钯合金的研究与开发

综述了钯合金成分和结构对透氢性能的影响,指出Ｐｄ－Ｒｅ系合金,尤其是Ｐｄ－Ｙ合金和化的Ｐｄ－２５ａｔ％Ａｇ透氢性能优越。有序无序转变对钯合金的透氢性能有影响。Ｐｄ－ＲＥ合金中有序无序转变研究较多的是Ｐｄ－Ｃｅ、Ｐｄ－Ｇｄ合金,但它们的透氢速率却都不如Ｐｄ－Ｙ合金。电阻测量的结果表明Ｐｄ－Ｙ合金中存在Ｐｄ３Ｙ型的短程有序结构,有人又发现该合金中存在Ｐｄ７Ｙ型的长程有序结构,是由Ｌ１２型的Ｐｄ３Ｙ转化     

Pd－8at％Y合金的有序无序转变

探讨了Ｐｄ－８ａｔ％Ｙ合金的有序无序转变。利用高温电阻法、ＸＲＤ法检验了该类合金的有序无序转变温度及相组成。结果表明，该类合金中存在Ｐｄ３Ｙ型长程有序相。Ｐｄ—８．２２ａｔ％Ｙ经９２０℃淬火＋７５０℃退火所得的有序结构较强。Ｐｄ—７．５２ａｔ％Ｙ有序无序转变温度Ｔｃ＝７００±１０℃。     

喷射沉积Al-3．8Li-0．8Mg-0．4Cu-0．13Zr合金的显微组织与拉伸性能

采用新型的喷射沉积快速凝固工艺制备了Ａｌ３．８Ｌｉ０．８Ｍｇ０．４Ｃｕ０．１３Ｚｒ合金，并对合金的显微组织与拉伸性能进行了实验研究。实验结果表明，沉积态合金组织为细小、均匀的等轴晶，晶粒尺寸大多在５～２０μｍ范围内。经热挤压后合金组织中的晶粒呈“砖块”状或“竹节”状形貌特征，晶界上破碎的氧化物很少。时效析出不规则形状的δ′相粒子和球壳状β′δ′复合沉淀相。δ′粒子的粗化速度较快，δ′粒子间距随时间增大的趋势不明显。喷射沉积ＡｌＬｉ合金短时间时效（１９０℃，１０ｈ）即可达到峰时效状态，此时材料的综合性能最优（σｂ＝５３４ＭＰａ，σ０．２＝４８０ＭＰａ，延伸率为１０％）。与粉末冶金ＡｌＬｉ合金相比，材料的塑性明显改善而强度相当。     

Pd(Ⅱ)-二溴对甲偶氮羧-吐温-80用于微量钯的分光光度测定

当吐温－８０存在时,Ｐｄ（Ⅱ）与二溴对甲偶氮羧的显色反应呈现了很高的灵敏度和选择性。其摩尔吸光系数ε６２３＝４．６＊１０＾４Ｌ．ｍｏｌ＾－１．ｃｍ＾－１,Ｐｄ含量在０．１－０．５μｇ．ｍｌ＾－１符合比耳定律,这种水相中直接测定微量钯的分光光度分析法已用于钯催化剂和二次阳极泥中微量钯的测定。     

钇抑制FeCrAl合金脆性的作用与合金中铬,钇含量的关系

Ｆｅ－（１５～２５）Ｃｒ－（４～５）Ａｌ合金在９００～１３００℃加热后发生高温脆化,脆化的温度－时间关系曲线与双曲线相似,在４００～５４０℃时效后发生４７５℃脆化,脆化曲线由一次脆化的“双曲线”和二次脆化的“Ｃ曲线”组成．在含０．２％～１．４％Ｙ的ＦｅＣｒＡｌ合金中,由于Ｙ－Ｆｅ相粒子俘获碳原子的作用,高温脆化和４７５℃脆化受到强烈抑制。时效时ａ相析出过程的发展使合钇合金抵抗脆化的能力随铬含量升高而降低。合金的抗脆化性能随钇含量升高而提高,含０．３％～０．４％Ｙ时最高。     

高钯合金捕集网中钯的状态

用ＸＰＳ研究了氨氧化装置中使用的高钯合金捕集网中钯的化学状态，新网中钯仅以Ｐｄ＾０一种形态存在（Ｐｄ３ｄ５／２，ＢＥ＝３３５．２ｅＶ）使用后，Ｐｄ３ｄ５／２ＢＥ值向高电子结合能力方向位移，钯的化学状态发生变化，以Ｐｄ和ＰｄＯ形态存在，定量测定了Ｐｄ＾０和ＰｄＯ浓度，发现Ｐｔ／Ｐｄ和ＰｄＯ浓度成反比，由此讨论了钯和高钯合金回收铂的机制。     

Pt—Pd—Rh合金的高温力学性能

在Ｐｔ－４Ｐｄ－３５Ｒｈ合金中将Ｐｄ含量增至１５ｗｔ％时,研究了Ｐｄ及少量Ｃｅ、Ｒｕ对合金在１０００℃以下高温力学性能的影响。实验结果表明在低温下Ｐｄ有一定的强化作用,但降低了合金的抗蠕变性能,而在合金中分别添加Ｃｅ（＜０１ｗｔ％）、Ｒｕ（＜０５ｗｔ％）后,合金的高温力学性能得以改善并优于Ｐｔ－４Ｐｄ－３５Ｒｈ合金,且Ｃｅ对合金的强化作用优于Ｒｕ。     

5—（3—羧基苯偶氮）—8—氨基喹啉光度法测定微量钯

合成了新试剂５－（３－羧基苯偶氮）－８－氨基喹啉（ｍ－ＣＰＡＱ）在弱碱性介质中,Ｔｗｅｅｎ－８０和ＴｒｉｔｏｎＸ－１００存在下ｍ－ＣＰＡＱ与Ｐｄ（Ⅱ）生成紫蓝色三元络合物,λｍａｘ＝６１５ｎｍ,ε１＝８．４×１０＾４Ｌ．ｍｏｌ＾－１．ｃｍ＾－１,Ｐｄ在０～３０μｇ／２５ｍｌ符合比尔定律,用于岩矿中微量Ｐｄ的测定,结果满意。     

贮氢电极合金Ml（NiMnTi）4.2Co0.8—XFex（x=0—0.8）的电化学性能

详细地研究了Ｍｌ（ＮｉＭｎＴｉ）４．２Ｃｏ０．８－ｘＦｅｘ（ｘ＝０－０．８）合金的电化学性能。试验发现,随着Ｆｅ含量ｘ从０增加至０．,合金的活化性能得到改善,但最大放电容量从３０２ｍＡｈ／ｇ逐渐降低到２８０ｍＡｈ／ｇ,高倍率放电性能从７８．５％缓慢降至７２．５％;当Ｆｅ含量ｘ≤０．４时,合金的自放电率与高Ｃｏ合金（ｘ＝０）相比有所降低,但当Ｆｅ含量ｘ超过０．４后,合金的自放电率较高Ｃｏ合金有所上升     

Effects of Post-weld Heat Treatment on Microstructure,Mechanical Properties and the Role of Weld Reinforcement in 2219 Aluminum Alloy TIG-Welded Joints

In as-welded state, each region of 2219 aluminum alloy TIG-welded joint shows diff erent microstructure and microhardness due to the diff erent welding heat cycles and the resulting evolution of second phases. After the post-weld heat treatment, both the amount and the size of the eutectic structure or θ phases decreased. Correspondingly, both the Cu content in α-Al matrix and the microhardness increased to a similar level in each region of the joint, and the tensile strength of the entire joint was greatly improved. Post-weld heat treatment played the role of solid solution strengthening and aging strengthening. After the post-weld heat treatment, the weld performance became similar to other regions, but weld reinforcements lost their reinforcing eff ect on the weld and their existence was more of an adverse eff ect. The joint without weld reinforcements after the post-weld heat treatment had the optimal tensile properties, and the specimens randomly crack in the weld zone.     

The First Phase of the SRIF Industrialized Base in ＂West Area＂ Has Been Put into Operation

After nearly two years＇ tense construction, the first phase of industrialized base of Shenyang Research Institute of Foundry （SRIF）, located at the Tiexi Casting and Forging Industrial Park in the west of Tiexi District, has now been completed and formally put into operation.     

Effect of Rare Earth Doping on Impedance,Modulus and Conductivity Properties of Multiferroic Composites:0.5(BiLa_xFe_(1-x)O_3)–0.5(PbTiO_3)

The Lanthanum-doped bismuth ferrite–lead titanate compositions of 0.5(Bi LaxFe1-xO3)–0.5(Pb Ti O3)(x = 0.05,0.10,0.15,0.20)(BLxF1-x-PT) were prepared by mixed oxide method.Structural characterization was performed by X-ray diffraction and shows a tetragonal structure at room temperature.The lattice parameter c/a ratio decreases with increasing of La(x = 0.05–0.20) concentration of the composites.The effect of charge carrier/ion hopping mechanism,conductivity,relaxation process and impedance parameters was studied using an impedance analyzer in a wide frequency range(102–106Hz) at different temperatures.The nature of Nyquist plot confirms the presence of bulk effects only,and non-Debye type of relaxation processes occurs in the composites.The electrical modulus exhibits an important role of the hopping mechanism in the electrical transport process of the materials.The ac conductivity and dc conductivity of the materials were studied,and the activation energy found to be 0.81,0.77,0.76 and 0.74 e V for all compositions of x = 0.05–0.20 at different temperatures(200–300 °C).     

Quantitative Analysis of the Crystallographic Orientation Relationship Between the Martensite and Austenite in Quenching–Partitioning–Tempering Steels

The orientation relationships(ORs)between the martensite and the retained austenite in low-and medium-carbon steels after quenching–partitioning–tempering process were studied in this work.The ORs in the studied steels are identified by selected-area electron diffraction(SAED)as either K–S or N–W ORs.Meanwhile,the ORs were also studied based on numerical fitting of electron backscatter diffraction data method suggested by Miyamoto.The simulated K–S and N–W ORs in the low-index directions generally do not well coincide with the experimental pole figure,which may be attributed to both the orientation spread from the ideal variant orientations and high symmetry of the low-index directions.However,the simulated results coincide well with experimental pole figures in the high-index directions{123}_(bcc).A modified method with simplicity based on Miyamoto’s work was proposed.The results indicate that the ORs determined by modified method are similar to those determined by Miyamoto’method,that is,the OR is near K–S OR for the low-carbon Q–P–T steel,and with the increase of carbon content,the OR is closer to N–W OR in medium-carbon Q–P–T steel.     

The Mirror with Patterns of Auspicious Animals and Grapes——Exquisite cast mirror and the technology of surface tin-enrichment by rubbing-in and infiltration of tin-rich powder

<正>Bronze mirrors were used by the Chinese people before the introduction of the glass mirror.Only after it was replaced by the glass mirror did the bronze mirror gradually retreat from people's lives.Different styles of bronze mirrors were made in different historical periods,particularly in the Warring States Period,the Han and Tang Dynasties,which were the three peaks of the development of bronze mirror arts in ancient China.The casting techniques were exquisite.The surface of the bronze mirror was smooth and bright enough to reflect one's image,and there were scarcely any casting defects on the mirror surface.On the back of the bronze mirror,there were rich depictions of Arts and Humanities,and the ornamentations were also     

The 9th China International Diecasting Congress & Exhibition

The 9th China International Diecasting Congress ＆ Exhibition was held on July 22-24, 2014 at Shanghai New International Expc Centre. This exhibition was the most successful over the years, with over 6890 visitors and 155 exhibitors, and the exhibition area increased by 30% from 9,500 square meters in 2012 to 12340 square meters. Die casting enterprises from a total of 24 countries and regions, including China mainland, Chinese Taiwan and Hong Kong, South Korea, Japan, Germany, India, Thailand, Malaysia, the United States, Russia, Australia, Iran, Ukraine, Brazil, Colombia, Singapore, Austria, Canada, Croatia, France, Turkey, United Kingdom, Vietnam, attended the congress and exhibition.     

Introduction of the Fluid Control Engineering Institute of Kunming University of Science and Technology

正The Fluid Control Engineering Institute of Kunming University of Science and Technology was set up in 1996.The researches of institute concentrate on electro-hydraulic(pneumatic)servo/proportional control and hydromechatronics.The Institute is committed to research and development of electro-hydraulic control of high-end technical equipment in ferrous metallurgy refining produc-     

RARE METALS Volume Contents

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Antimony Induced Crystallization of Amorphous Silicon

Antimony induced crystallization of PVD (physics vapor deposition) amorphous silicon can be observed on sapphire substrates. Very large crystalline regions up to several tens of micrometers can be formed. The Si diffraction patterns of the area of crystallization can be observed with TEM (transmission electron microscopy). Only a few and much smaller crystals of the order of 1μm were formed when the antimony layer was deposited by MBE (molecular beam epitaxy) compared with a layer formed by thermal evaporation. The use of high vacuum is essential in order to observe any Sb induced crystallization at all. In addition it is necessary to take measures to limit the evaporation of the antimony.     

A CUMULATIVE FATIGUE DAMAGE RULE UNDER THE ALTERNATIVE OF CORROSION OR CYCLIC LOADING

Fatigue damage increases with the applied loading cycles in a cumulative manner and the material deteriorates with the corrosion time. A cumulative fatigue damage rule under the alternative of corrosion or cyclic loading was proposed. The specimens of aluminum alloy LY12-CZ soaked in corrosive liquid for different times were tested under the constant amplitude cyclic loading to obtain S-N curves. The test was carried out to verify the proposed cumulative fatigue damage rule under the different combinations among corrosion time, loading level, and the cycle numbers. It was shown that the predicted residual fatigue lives showed a good agreement with the experimental results and the proposed rule was simple and can be easily adopted.