Abstract:介绍了磁致冷材料磁热效应的表征方法，概述了国内外各温度区间磁致冷材料的研究进展。在20K以下温区，磁致冷材料研究主要集中在具有高导热率、低点阵热容和极低有序化温度的石榴石，如Gd3Ga5O12(GGG)，Dy3Al5O12(DAG)，Gd3Ga5-xFexO12(GGIG)及Er基磁致冷材料；20K～77K温度区间，磁致冷材料研究主要集中在重稀土金属间化合物中，如(Dy1-xErx)Al2复合材料等；在室温附近，具有大磁热效应的磁致冷材料以稀土Gd，Gd5(SixGe1-x)4(0≤x≤0．5)和MnFeP1-xAsx(0．15≤x≤0．66)合金为代表，特别是Gd5Si2Ge2(Tc=274K)和MnFeP0.45As0.55(Tc=300K)合金，在磁场5T下具有巨磁热效应，是Gd的2倍以上。总结了各温度区间磁致冷材料的选择依据。重点评述了室温磁致冷材料的最新研究成果，展望了室温磁致冷材料的发展前景。

Abstract:Nodular corrosion a local corrosion occurring on the surface of zirconium alloys usually in boiling water reactors (BWR), directly affects service life of the zirconium cladding and threatens the safety of reactors. The occurrence, propagation morphology of nodules and other characteristics of nodular corrosion, are summarized. The commonly accepted models of nodular corrosion include the hydrogen accumulation model of KUWAE[ref] and nucleation & growth model of ZHOU[ref]. Main driving factors include surface condition, heat treatment, alloying composition, presence of second phase particles and irradiation. Processes to suppress nodular corrosion are presented in the present paper, for instance: increasing the Fe+Cr content, decreasing the Sn content, decreasing the annealing time and temperature, improving the surface finish. But, the most effective means of improving nodular corrosion resistance is to use a new zirconium alloy containing niobium.

Abstract:The field variables model has recently emerged as a powerful approach for simulating microstructure evolution in materials. It describes the microstructure using a set of conserved and non-conserved field variables in the form of higher order differentials. It can predict and control complex microstructure evolution with these field variables by computer simulation. This paper reviews the fundamental principle of the field variables model and recent progress in the field of materials science and engineering.

Abstract:The effects on the electrochemical properties of AB5-type hydrogen storage alloys for Ni-MH batteries of adding elements to the A-side and the B-side are described. Advances in the worldwide development of low-Co or Co-free hydrogen storage alloys are reviewed. Considered are: component design, preparation technique, heat treatment and surface treatment. Prospects for the further development of low-cost hydrogen storage alloys and Ni-MH battery for electric vehicles (EVs) power are discussed.

Abstract:为了研究铈,钇离子注入对纯锆耐蚀性的影响,纯锆样品用MEVVA源以40 kV注入1×1016 ions/cm2至1×1017 ions/cm2剂量的钇和铈,注入最高温度约为150℃.用X光电子谱仪(XPS)分析注入表层元素的价态;在1 mol/L硫酸溶液中3次极化测量来研究注入样品的耐蚀性.对于钇离子注入,当注入剂量大于5×1016 ions/cm2时,注入样品的耐蚀性显著提高.用掠角X射线衍射(GAXRD)研究氧化膜中由于铈离子注入发生的相转移.三次极化测量表明注铈样品与空白样品相比,耐蚀性下降许多.最后分别对注入钇和铈样品的腐蚀行为机理进行了探讨.

Abstract:The modifying effects of a new type of Al-P master alloy on eutectic and hyper-eutectic Al-Si alloys were investigated. It is found that excellent modifying effect on these alloys can been obtained by adding the new type of Al-P master alloy. It is also found that the modifying efficiency of the Al-P master alloy can be improved by the addition of Al-8Ti-2C master alloy to the Al-Si melt. When the content of TiC particles (by Al-8Ti-2C master alloy) in the Al-24Si melt is 0.03%, the average and largest grain size of primary Si can be decreased to 41 m, 55 m from the original 47 m and 75 m. The modifying effect occurs after 50 minutes from adding the Al-P master alloy and the TiC particles, and remains steady with the increase in holding time. The average grain size of the primary Si can be decreased to 30 m from 50 m when the content of TiC particles in Al-12Si melt is 0.03%.

Abstract:通过时效硬化曲线测量及时效组织分析，研究了微量钪对Al-15Ag合金时效行为和显微组织的影响。在Al-15Ag合金中添加0．2％Sc(质量分数，下同)，可以增强合金在190℃和350℃时效的时效硬化效果，延长峰时效的到达时间。微量钪的添加促使合金中y’相细小密集地析出，同时钪的存在减少了y’相宽面上的位错台阶数。含钪Al-15Ag合金中y’相长大过程比较缓慢的微观机理是微量钪的添加影响了合金中y’相宽面上的台阶分布。

Abstract:Cu/Ni multilayers with various modulation wavelengths were deposited on a low carbon steel substrates by electrode positing method. Hardness measurements identified that the relationship between the yield strength (one-third of hardness) which increased with decrease of layer thickness for Cu/Ni multilayers and single layer thickness at sub-micron length scale--- could be described by the Hall-Petch (H-P) formula for dislocation pile-up. In the regime of few tens to a hundred nanometer of single layer thickness, the dislocation pileup-based H-P model breaks down. This can be explained in terms of the limiting dislocation size criterion proposed by Cheng et al.

Abstract:The effect of pressure annealing on the glass transition of bulk amorphous Zr55Cu30Al10Ni5 is studied by x-ray diffraction and differential scanning calorimeter (DSC). The apparent activation energy of the glass transition (Eg) was determined by the Kissinger method. The results show that the glass transition temperature and Eg of the specimens change nonlinearly with increase of the annealing pressure. The role of pressure on structural relaxation and the glass transition is discussed.

Abstract:The ternary alloy LaMg17Ni was prepared by mechanical alloying (MA) and its thermodynamic and kinetic properties were examined. This composite possesses high hydrogen storage capacity of 5.23 mass% at 553 K. Under 3.0 MPa hydrogen pressure, the alloy can absorb more than 90% of its full hydrogen capacity in less than 1 min at 423 K~573 K. X-ray diffraction and SEM were used to characterize the crystal structure, microstructures, and composition of the composite sample. It was found that the MA sample contained a mixture of La2Mg17, Mg2Ni, LaH2 and La particles. The kinetics of the sample was assisted the by catalytic action of Mg2Ni and La as well as the existence of the multiphase structure formed in the preparation process.

Abstract:Differential Scanning Calorimetric(DSC) techniques are used to study the precipitation behaviour of 7075 aluminum alloys and the influence of Li on the microstructure transformation of the7075-Li alloy during aging. The kinetic parameters for GP zones and h phase dissolution are calculated in 7075 and 7075+Li alloys. The results show that Li slightly affects the activation energy for GP zones dissolution, but markedly raises the activation energy for h phase dissolution.

Abstract:A pure quasicrystal with the composition Ti40Zr40Ni20 was obtained in bulk form by using conventional suction-casting. The quasi-lattice constant of the icosahedral phase (I-phase) is 0.523 nm. Differential scanning calorimetry (DSC) together with X-ray diffraction were used to study the temperature-induced phase transformation of the as-cast I-phase. Two endothermic reactions are identified in the DSC trace. The first endothermic reaction with an onset temperature of 964 K corresponds to eutectoid transformation from the I-phase to the C14-type Laves phase and -Zr(Ti) solid solution. The second one with an onset temperature of 1 107 K indicates the melting transformation of the eutectoid mixture.

Abstract:讨论了TiMn0.85Cr0.35V0.3合金的活化性能和吸放氢性能。活化性能的结果表明：合金表面氧化层的形成是影响合金活化的重要因素。空气中暴露30d的TiMn0.85Cr0.35V0.3合金粉，在P=1MPa，r=293K下，经几次活化循环后即可基本完全活化。PCT结果表明：退火处理可明显改善该合金的储氢性能。在1223K下退火6h的该合金在273K时的有效放氢量Ce、吸氢平台压力Pa和放氢平台压力Pd分别为1．55％(质量分数)、0．141MPa和0．112MPa。符合作为燃料电池供氢源的应用要求。

Abstract:讨论了环状亚砜衍生物OTMSO萃铂的性能和机理。随着萃取剂浓度和水相中酸度的增加,萃取率上升。萃铂反应是放热反应。应用斜率法探讨了COTMSO,CH+和CCl-对分配比的影响。亚砜的配位数是2,CH+对分配比的影响很大。用红外光谱确定了配位原子。亚砜以酸性缔合机理萃铂,萃合物的组成为(H+·h1H2O·OTMSO)2PtCl62-,萃合物发生内配位转变、亚砜进入萃合物内界,通过亚砜S=O中的硫与铂配位。

Abstract:研究了含氢量为110μgg/和280μg/g的Ti-4Al-2V钛合金在不同载荷比下的疲劳裂纹扩展行为。载荷比降低，da/dN曲线向高△K方向移动，并逐渐不出现疲劳裂纹的近门槛扩展阶段；无论载荷比和含氢量的高低，稳态裂纹扩展区的裂纹扩展行为符合Paris幂律关系，即da/dN=C(△K）^m；含氢量为110μg/g时，载荷比对稳态裂纹扩展区的da/dN没有影响；含氢280μg/g时，载荷比降低，稳态裂纹扩展区的da/dN也降低；载荷比影响裂纹由近门槛扩展区进入稳态裂纹扩展区的应力强度因子范围△Kp和开始失稳扩展的应力强度因子范围△K1H。载荷比越小，△Kp和△K1H越大。

Abstract:The field strength distribution of the magnetic circuit vs the NdFeB permanents was calculated in the condition of the same magnetic structure. The permanents were possessed of the same volumes and configurations, but different performaces, and there was the same width of air-gap in the magnetic circuit. Their field strength magnitudes were compared and the factors of influence on magnetic field strength were analyzed . According the results it is necessary comprehensively to consider magnetic-energy-product, coercive force, remanence etc rather than to emphasize the materials with high magnetic-energy-product upon designing the permanent magnetic field for magnetic refrigeration so as to provide the proper basis for selecting materials in designing the magnetic field for room-temperature magnetic refrigirators.

Abstract:研究了1种新型的亚稳定β钛合金(Ti-B20)在不同热处理制度下的显微组织与拉伸和冲击性能。结果表明，热处理制度的改变能显著影响该合金的显微组织和强化行为。固溶温度是影响合金时效后塑性的首要因素，而时效温度是影响强度的主要原因。时效温度降低，析出相更加细小，因此合金强度升高。而粗大的晶粒及连续的晶界容易产生应力集中，因此合金经β固溶时效后具有较低的塑性和冲击值。通过在β相变点下固溶，然后在550℃～600℃之间合适的温度下时效处理，可以获得强度，塑性和冲击韧性的良好配合。

Abstract:The brazing of SiC particulate reinforced LY12 alloy matrix composite has been carried out by using the high-frequency induction vacuum brazing process with Al-28Cu-5Si-2Mg filler.The results showed that brazing temperature, holding time, SiC particle volume percentage and post heat treatment condition combine to influence the joint strength of SiCp/LY12. The SiC particles occur in the brazing seam and the distribution of SiC particles in the joint is not as uniform as that in the composites. Particle-poor zones in the joint exist near the base metal, and particle-rich zones exist in the center of the brazing seam. In addition, the results indicate that the failure of the composite is predominantly initiated by microcracks initiating at the SiC particle in the brazing seam and propagated along it with low energy.

Abstract:The characterizations of Ti/SnO2+Sb2O3/PbO2 anodes with SnO2+Sb2O3 as an intermediate layer obtained by way of a polymeric precursor, and using ethylene glycol, ethanol and n-butanol for different precursor solvents were studied. The microstructure, morphology of the SnO2+Sb2O3 layers derived from different precursor solvents and the top PbO2 active layers were examined using by XRD and ESEM. The lifetime and the electro-catalytic activity of Ti/SnO2+Sb2O3/PbO2 anodes with the intermediate layers prepared from different precursors were also assessed by the polarization method and the accelerated lifetime test in 1.0 mol/L H2SO4 solutions. The results showed that the microstructure and, morphology of the SnO2+Sb2O3 layers were correlated to precursor solvents. The intermediate layer made from a polymeric precursor was more compact, homogeneous, possess better surface smoothness, and a higher content of SnO2 and Sb2O3 as compared with that from the other solvents. Thus the Ti/SnO2+ Sb2O3/PbO2 anode prepared from the polymeric precursor had a longer lifetime than that with other solvents, but the intermediate layers prepared from different precursor solvents had little effect on the electro-catalytic activity of Ti/SnO2+Sb2O3/PbO2 anodes.

Abstract:采用快速凝固和热压的方法制备了p型热电材料Fe0.92Mn0.08Six(x=1.9, 2.0, 2.1, 2.3, 2.5).X射线衍射分析表明,热压试样退火24 h后,完全转变为β半导体相.所有试样的致密度均高于90%.测量试样的电学性能发现,原料配比为Fe0.92Mn0.08Si2.1的试样在整个测量温度范围内的功率因子最大,550℃时达到了400 μW·m-1·K-1以上.

Abstract:The effect of different stages of the partial melting process on the phase component and microstructure of (Bi,Pb)-2223/Ag strip was analyzed and compared to the normal two-stage heat treatment process. The results show that some of the (Bi,Pb)-2212 phase melted and decomposed into (Sr,Ca)2CuO3, (Sr,Ca)Cu2O3 and rich (Bi,Pb) liquid phase. At the same time, the (Sr,Ca)2CuO3 and (Sr,Ca)Cu2O3 phases grew rapidly. During cooling and phase formation, the (Sr,Ca)2CuO3 and (Sr,Ca)Cu2O3 phases stop growing when they reach a certain size and react with liquid phase to recreate the (Bi,Pb)-2212 phase with good orientation. At the phase formation stages, the (Bi,Pb)-2223 phase during transformation from the (Bi,Pb)-2212 phase inherits the good orientation of (Bi,Pb)-2212 phase. This results in an improvement in the texture and the density of the (Bi,Pb)-2223 phase which in turn results in an improvement of the critical current. The final strip made by the partial melting process has a critical current of 51 A (while the strip made by the normal two-stage heat treatment process have the lower critical current of 36 A). Thus the new method increases the critical current by about 40%.

Abstract:The structural and hydriding behaviours of the alloy LaMg11Ni after modification by mechanical grinding in tetrahydrofuran (THF) were investigated. The influence of mechanical grinding in THF on surface activation was evaluated by studying the hydrogen absorption/desorption kinetics. The alloy possesses high hydrogen storage and excellent kinetic behaviour, even at moderate temperatures. For the LaMg11Ni alloy milled in THF for 20 h, the hydrogen content of 3.4wt.% was obtained at 448 K and 3.2 MPa H2 after the initial exposure to hydrogen. An even higher hydrogen content of 3.65wt.% was obtained under the same conditions after several hydriding/ dehydriding cycles. Auger electron spectroscopy (AES) was used to determine the surface characteristics of the modified alloy. The modified alloy exhibits a rather high surface activity which improves with increase of milling time. According to XRD analysis the alloy modified by milling THF, show some degree of amorphousness.

Abstract:Nano-ZnO powder was prepared by using Zn(NO3)2 and (NH4)2CO3 as starting materials. The aggregation of nano-ZnO powder particles was studied by the Zeta potential system, infrared absorption spectra, XRD and SEM. The results showed that a suitable dispersant added to the ZnO precursor could increase the static potential of nano-ZnO powder, which would restrain aggregation of the precursor during the drying and calcining process. In this way, the dispersed state of the ZnO nano-powder is improved. The particle size of prepared ZnO powder is less than 20 nm. Secondary particle size is less than 80 nm.

Abstract:Single domain bulk Gd-Ba-Cu-O superconductors 17 mm in diameter have been successfully grown by powder-melt-processing (PMP) in air. The superconducting properties of Gd-Ba-Cu-O may be improved by substituting Gd2O3 for Gd211 addition and the cost of preparation can be decreased. However a solid solution of Gd-Ba forms in response to the inclusion of excess Gd2O3, and the superconducting properties of the bulk Gd-Ba-Cu-O decrease. The addition of 0.15 mol percent of Gd2O3 is found to be optimal and leads to a trapped field of 0.36 T at 77 K.

Abstract:分析了TC18钛合金表面喷丸强化所产生的表面形貌、表面粗糙度、表面残余应力和表面层残余压应力场变化及喷丸对拉-拉疲劳性能的影响,并用疲劳裂纹萌生的微细观过程理论合理解释了拉-拉疲劳极限的提高。结果表明:喷丸强化不仅能够明显延长TC18钛合金的高周疲劳寿命,且能使1×107周次下的疲劳极限提高27%。

Abstract:A hydrosol of coexisting AgCl and Cu2+ was prepared by the precipitation method. The organosol of coexisting AgCl and Cu2+ was obtained by using oleic acid to extract and modify the nanoparticles in hydrosol, TEM photos showed that the AgCl nanoparticles were spherical in shape, and about 50nm in size. The particle size distribution was narrow and no agglomerates were observed. ED imaging indicated that the AgCl nanoparticles were polycrystalline in structure, and some of AgCl existed as monocrystalline particles. AgCl nanoparticles coated with oleic acid easily dissolved in weak polar solvents, but would not dissolve in polar solvents.

Abstract:Nanometer ZnO-base composite oxides were prepared by the inorganic salt sol-gel(ISG) method, and their structures were studied using XRD. The gas sensors were prepared from the nanometer ZnO-base composite oxides, and their sensing properties to different concentration of C2H5OH gases were investigated. A composition of Al/ZnO=1.5 mol% sensor shows a maximum sensitivity of 26 to 2 000 g/g C2H5OH. The composite oxide Sb/Al/ZnO=5?3?100(mol)% has good gas sensing properties over wider working temperature range. The physical and chemical adsorptions and the gas-sensing mechanism of the composite oxide Sb/Al/ZnO were discussed.