甘氨酸-硝酸盐法制备NiO-Sm掺杂CeO2复合阳极粉末研究

采用甘氨酸-硝酸盐燃烧法合成了中温固体氧化物燃料电池NiO-SDC复合阳极粉末。通过XRD和扫描电子显微镜对不同甘氨酸／金属离子摩尔比合成的复合粉末的结构和形貌进行了研究。XRD结果表明，直接燃烧合成的复合粉末除了NiO和CeO2的衍射峰外，还有Ni2O3衍射峰存在，粉末经900℃煅烧2h后Ni2O3峰消失，表明形成了NiO-SDC复合阳极粉末。氢气条件下的热重分析表明，复合粉末中NiO和SDC两相比例与溶液组分配比基本一致。制备的不同NiO含量薄膜阳极的电解质支撑单电池性能测试结果表明，阳极为60％NiO-SDC的单电池具有最高的开路电压。     

燃烧法制备中温SOFC电解质及其电极材料

采用一种新的燃烧合成陶瓷粉体的方法——硝酸盐-柠檬酸盐燃烧法低温合成中温SOFC所有元件的初始粉体并组装成单电池，电池的电解质材料为Ce0.8Gd0.2O1.9，阴极材料为掺杂一定量固体电解质的La0.6Sr0．4Fe0.8Co0.2O3，阳极材料为固体电解质与NiO的复合材料。单电池的性能测试结果表明：单电池的输出电压和输出电流皆随其运行温度升高而增大，同时单电池的开路电压随温度升高而下降。以Ce0.8Gd0.2O1.9电解质材料为电解质的单电池在750℃的最大输出功率密度约为85mW／cm^2。     

燃烧法制备中温SOFC电解质及其电极材料

采用一种新的燃烧合成陶瓷粉体的方法--硝酸盐-柠檬酸盐燃烧法低温合成中温SOFC所有元件的初始粉体并组装成单电池,电池的电解质材料为Ce0.8Gd0.2O1.9,阴极材料为掺杂一定量固体电解质的La0.6Sr0.4Fe0.8Co0.2O3,阳极材料为固体电解质与NiO的复合材料.单电池的性能测试结果表明:单电池的输出电压和输出电流皆随其运行温度升高而增大,同时单电池的开路电压随温度升高而下降.以Ce0.8Gd0.2O1.9电解质材料为电解质的单电池在750℃的最大输出功率密度约为85 mW/cm2.     

燃烧法制备SOFC用Ni/YSZ阳极材料

以Y(NO3)3、Zr(NO3)4、Ni(NO3)2和有机燃料为原料,采用低温燃烧法制备了NiO/YSZ复合粉料,然后于800℃在H2中还原制备了Ni/YSZ阳极材料.研究了燃烧合成过程中氧化物与有机燃料的配比对反应产物的影响.结果表明当氧化物与燃料的比例为23时,低温燃烧后可成功合成结晶充分的NiO/YSZ粉体.对合成粉体的SEM、TEM观察以及制备的Ni/YSZ阳极材料的SEM观察结果表明,低温燃烧合成的NiO/YSZ粉体细小且两相混合均匀,颗粒粒径为0.5 μm～1 μm.与机械混合法相比,采用燃烧法合成粉体,干压成型制备的Ni/YSZ阳极材料,不仅Ni在YSZ基质中分布更均匀,而且金属陶瓷中的两相均形成了连续的网络结构.     

掺杂复合稀土氧化物对W-20Cu复合材料组织与性能的影响（英文）

以偏钨酸铵和硝酸铜为原料,采用EDTA-柠檬酸法制备了含有0%～0.8%(质量分数)稀土氧化物(Ce_(0.8)Sm_(0.2)O_(1.9),SDC)的W-20Cu复合粉体,所制备的复合粉体经压制成形、1250℃烧结2 h后获得SDC/W-20Cu复合材料烧结体。对所制备复合粉体进行物相、形貌的表征;研究稀土氧化物的添加对SDC/W-20Cu烧结体的密度、组织结构和物理力学性能的影响。结果表明:所制备的W-Cu复合粉体平均粒度为100～200 nm;同时,SDC的添加对烧结体的密度和电导率会有轻微的影响,但能够抑制晶粒的长大并明显改善烧结体的力学性能。经1250℃烧结后,SDC/W-20Cu烧结体的相对密度均高于97%;当SDC的添加量为0.6%时,具有最大的抗弯强度和显微硬度HV,分别是1128 MPa和3180 MPa;此外,在室温和600℃的测试条件下,其最大的抗拉强度分别可以达到580和258 MPa。     

复合稀土氧化物掺杂W-20Cu复合材料的制备及组织性能研究

以偏钨酸铵和硝酸铜为原料,采用EDTA-柠檬酸法制备了含有0~0.8wt.%稀土氧化物( Ce_0.8Sm_0.2O_1.9, SDC)的W-20Cu复合粉体,所制备的复合粉体经压制成型、1250°C烧结2h后获得SDC/W-20Cu复合材料烧结体。对所制备复合粉体进行物相、形貌的表征;研究稀土氧化物的添加对SDC/W-20Cu烧结体的密度、组织结构和物理力学性能的影响。实验结果表明：所制备的W-Cu复合粉体平均粒度为100~200nm;同时,SDC的添加对烧结体的密度和电导率会有轻微的影响,但能够抑制晶粒的长大并明显改善烧结体的力学性能。经1250°C烧结后,SDC/W-20Cu烧结体的相对密度均高于97%;当SDC的添加量为0.6%时,具有最大的抗弯强度和显微硬度,分别是1128MPa和258HV;此外,在室温和600°C的测试条件下,其最大的抗拉强度可以达到580MPa和258MPa。     

甘氨酸-硝酸盐法合成高烧结活性氧化铈电解质粉体

用甘氨酸-硝酸盐法合成了适用于中低温固体氧化物燃料电池的电解质材料Ce0.8Gd0.05Y0.15O1.9,主要分析了甘氨酸/硝酸根比值对燃烧合成过程、制得粉体结构、粒度和形貌的影响,并对其烧结性能作了评价.     

控制结晶法合成球形正极材料LiNi0.8Co0.2O2及其电化学性能

采用控制结晶法制备锂离子电池用高密度球形正极材料LiNi0.8Co0.2O2。对前驱体Ni0.8Co0.2(OH)2制备工艺进行优化,在金属盐溶液流速为8 mL/min,搅拌速率450 r/min,pH值为11.5,氨浓度20 g/L反应36 h的条件下,合成了振实密度为2.02 g/cm3的球形Ni0.8Co0.2(OH)2。并以Ni0.8Co0.2(OH)2为原料,与LiOH.H2O进行混合研磨进行高温烧结,考察烧结制度对合成材料LiNi0.8Co0.2O2电化学性能的影响。在Li/(Ni Co)配比为1.05、氧气流量为800 mL/min,750℃下烧结16 h所得材料LiNi0.8Co0.2O2电化学性能最优:在0.2 C,3.0~4.3 V的条件下,首次放电容量达到195.4 mA.h/g,循环50次后容量保持率达到89.2%。     

高容量正极材料Li[Li0.2Ni0.2Mn0.6]O2的合成及电化学性能

以LiOH.H2O、Ni(OH)2和Mn3O4为原料,采用固相法合成锂离子电池正极材料Li[Li0.2Ni0.2Mn0.6]O2。通过X射线衍射(XRD)、扫描电子显微镜(SEM)对所得样品的结构和形貌进行表征,并测试了该材料的倍率性能和高低温性能。结果表明:900℃下烧结10 h后可获得晶粒细小均匀的层状Li[Li0.2Ni0.2Mn0.6]O2材料,并具有良好的电化学性能,放电容量最高可达235.9 mA.h/g;在50℃下测试时该材料的放电容量高达284.4 mA.h/g,并表现出良好的循环性能,其倍率性能和低温性能还有待进一步改善。     

尿素均相沉淀法制备纳米粉体Ce0.8Sm0.2O1.9的烧结性能

以尿素为沉淀剂,Sm2O3和Ce(NO3)3.6H2O为起始原料,采用均相沉淀法制备Sm3+掺杂CeO2基纳米固溶体Ce0.8Sm0.2O1.9(SDC)。利用TG-DTA、XRD、SEM和BET等手段对前驱体的热分解行为和SDC粉体的性能进行表征,研究焙烧温度对SDC粉体粒径和烧结性能的影响。结果表明:随焙烧温度的升高,晶粒尺寸逐渐增大;700℃焙烧的前驱体是具有良好结晶性能的类球形萤石型结构固溶体,晶粒尺寸为15 nm,粒子间仅有较弱的软团聚;该粉体具有较好的成型和烧结性能,将素坯在1 400℃保温2 h,得到相对密度高于95%、平均粒径约为0.6μm的固体电解质陶瓷体。     

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.