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Abstract:The Al2O3/Ni composite brush plating coating with homogeneous distribution and good bonding with matrix metal Ni was prepared through adding nano-Al2O3 grains into the Ni-base electro-brush plating bath. The microstructures of the composite brush plating coating are superior to the common rapid Ni-base brush plating coating. The tribological results show that the abrasion-proof of the composite plating coating is better than that of the common plating coating not only at room temperature but also at high temperature. It is found that the plastic deformation-resistance and adhesion reduction performances of the composite plating coating were improved under strengthening effect of nano-Al2O3 grains.

Abstract:LiMnO2 and LiMn0.9Cr0.1O2 were prepared by a high temperature solid-state route. In comparison with orthorhombic LiMnO2, monoclinic LiMnO2 was formed with Cr substitution. The research shows that the irreversible transformation to spinel-like structure during LiMnO2 cycling is a gradual phase transformation process. In comparison with the 2.9 V and 4 V plateaus of LiMnO2, LiMn0.9Cr0.1O2 shows only 2.9 V plateau for further cycling. So it is clear that the electrochemistry behavior change from LiMnO2 to LiMn0.9Cr0.1O2 phase is due to doping of Cr.

Abstract:為了提高Bi-2212/Ag帶的性能（主要指臨界電流密度Jc)，進(jìn)行了部分熔化熱處理工藝對(duì)帶材Jc的實(shí)驗(yàn)。采用標(biāo)準(zhǔn)的4點(diǎn)法測(cè)量Jc,使用PW1700XRD,SL20 SEM 和EDX檢驗(yàn)和研究帶材的相組成和微觀組織。實(shí)驗(yàn)表明，在流氧氣氛下，燒結(jié)溫度為860℃～880℃時(shí)，前驅(qū)粉末以Bi-2212為主相，同時(shí)含有少量的Bi-2201相，（Sr2Ca)Cu2O3相和富（Bi2Sr)相。在流氧氣氛下，帶材Jc性能對(duì)熱處理工藝參數(shù)非常敏感，在實(shí)驗(yàn)條件范圍內(nèi)，優(yōu)化后的熱處理工藝參數(shù)為：熔化溫度Tmax=890℃，熔化時(shí)間tmax=10min,冷卻速率Rc=2℃h^-1，在保溫溫度為835℃時(shí)，保溫時(shí)間ta=20h,通過優(yōu)化的部分熔化熱處理工藝，在77K，0T下最后所制得帶材的最大Jc=6A,Jc=890Acm^-2.

Abstract:By analyzing the kinetics of thermal debinding, shifting of different controlling mechanism was found in the debinding process. The definition of critical thickness was specifically put forward for the first in this article. Big critical thickness means fast initial heating can be performed, which means the time for debinding can be comparatively shorter. To avoid defects such as blisters, cracks and distortion, heating of compacts with small critical thickness should be very slow. In debinding practice big critical thickness is more favorable. Theoretical calculation of controlling steps show that critical thickness depends on the flowing factor: powder size, debinding temperature and solid loading; its directly proportional to powder sizes, its inversely proportional to temperature and solid loading rate.

Abstract:Abnormal morphology appears easily in the cross section of cold-pilgered zirconium alloy bar due to improper die design or/and improper deformation ratio distribution. Causes and its effects on usability were investigated in this paper by optical microscopy(OM), scanning electron microscopy(SEM), X-ray diffraction(XRD), hardness and density, etc. Studying results prove that such abnormal phenomena are not exhibition of defects; however result from preferred orientation with low acid corrosion resistance brought by cold pilgering; such abnormal phenomena have no effects on usability of cold-pilgered bars, cold-pilgered zirconium alloy bar with abnormal phenomena can still serve reactors safely.

Abstract:The effects of small addition of scandium on the microstructure and ageing characteristics in Al-2.5Cu-1.5Mg alloys have been investigated. The results indicate that the age hardening response of the Al-2.5Cu-1.5Mg alloy can be enhanced while the general form of the ageing curve is not altered by small addition of Sc. TEM observations show that GPB can only precipitated during the second age hardening period which will make a great contribution to the age hardening, and the morphology of GPB can be modified by the small addition of Sc, which does result in a refinement of the distribution of GPB in Al-2.5Cu-1.5Mg-0.2Sc.

Abstract:以流體力學(xué)和熱力學(xué)理論為基礎(chǔ)，結(jié)合金屬注射成形的特點(diǎn)，建立了其充模流動(dòng)過程中的控制方程、初始條件和邊界條件，并以硬質(zhì)合金材料為例，采用大型有限元軟件ANSYS進(jìn)行了計(jì)算數(shù)值模擬，求解了流體前沿、溫度場(chǎng)、壓力場(chǎng)，同時(shí)結(jié)合實(shí)驗(yàn)分析了金屬注射成形過程中的幾種常見缺陷的產(chǎn)生條件。模擬結(jié)果表明：當(dāng)采用中間澆口、模溫60℃、料溫160℃、體積流速在40cm^3／s～70cm^3／s的范圍內(nèi)進(jìn)行注射可以得到良好的硬質(zhì)合金Ⅰ型拉伸試樣預(yù)成形坯。該結(jié)論與實(shí)驗(yàn)結(jié)果一致。

Abstract:采用循環(huán)水淬和脈沖激光沖擊法并結(jié)合有限元計(jì)算考察和分析了用超高壓梯度燒結(jié)方法制備的W／Cu FGM的抗熱震性能。結(jié)果表明，W／Cu FGM經(jīng)受50次800℃～25℃水淬沖擊和100MW／m^2以上的激光循環(huán)沖擊，沒有出現(xiàn)界面破壞現(xiàn)象；但隨著熱沖擊次數(shù)及沖擊能量密度的增加，金屬W表面產(chǎn)生了裂紋、晶間斷裂以及出現(xiàn)液相及蒸發(fā)現(xiàn)象。與非梯度材料相比，W／Cu FGM有優(yōu)異的抗熱沖擊性能，大致可以經(jīng)受100MW／m^2 350次以上的激光循環(huán)沖擊。

Abstract:The specific heat capacity of ternary liquid Al85Ni10M5 alloys (addition elements M include Si, Mn, Ti and Ce) has been investigated using differential scanning calorimetry (DSC). Experimental results show that a hump occurs on the curve of specific heat capacity of Al85Ni10M5 alloys at elevated temperatures. The position of the hump shifts to a higher temperature with increasing atomic radius and decreasing electronegativity of addition elements. Furthermore, the specific heat capacity of ternary liquid Al85Ni10M5 alloys tends to descend at higher temperatures. The variation of specific heat capacity of liquid alloys with temperature shows that the micro-inhomogeneity exists in the liquid alloys.

Abstract:The 7075 aluminum alloy is forged at different strain in different ways. OM(optical microscope) and TEM(transmission electric microscope) were employed to observe the microstructure of 7075 aluminum alloy after hot deformation. Experiment results indicated that 7075 aluminum can occur dynamic recrystallization under hot forging and fine grain can be obtained at the same time, whose recrystallization mechanism and nucleation mechanism are discontinuous dynamic recrystallization and subgrain rotation and polymerization respectively. Its critical strain value is related to deformation pass, the more passes are, the smaller critical strain value will become. Recrystallized grain size decreases with increase of strain, and dispersed second-phase particles play a very important role during dynamic recrystallization.

Abstract:Many H+ response characteristics of Iridium oxide electrode were described in this paper. The linear relationship between open-circuit potential and pH value, decisive factors to response rate were studied in detail. The hysteresis effect were also investigated, furthermore, many determination technologies, such as cyclic voltammetry, SEM, XPS were used to analyze the element valence and composition or to decide the rate of inner and outer surface, as well as to observe the morphology of the oxide film, from which the relationship between hysteresis effect and film thickness as well as morphology was discussed, finally, the response mechanism of the hydrous iridium oxide electrode were suggested.

Abstract:The phase structure and dislocations in rapidly solidified AZ91D magnesium alloy were studied by TEM and XRD techniques. It shows that under rapid solidification conditions, the common eutectic transformation La-Mg+ Mg17Al12 in AZ91D alloys is suppressed to a great extent. As a consequence, the rapid solidification microstructures consist dominantly of supersaturated a-Mg solid solution, whose size is in the range of 0.8~6.0 m. TEM analysis reveals that little amount of oval Mg17Al12 granules, trace polygonal Al8Mn5 particles and very small anomalistic -AlMg phase with the size of 5~70nm precipitate in a-Mg grains or their boundaries. The -AlMg phase is metastable transition configurations which is further transformed into stable Mg17Al12 phase. There are large numbers of dislocation pile-up and cells with the size of 0.2~0.7m in a-Mg grains, and the high dense dislocations mainly concentrate on the (002) close-packed face and exhibit a remarkable orientation.

Abstract:利用電子能量損失譜(EELS)和俄歇電子能譜(AES)研究室溫下鈮的初始氧化過程，研究表明：清潔表面鈮的EELS的實(shí)驗(yàn)值與理論值較為符合；隨著氧化程度的加劇，其體等離子體(BP)、表面等離子體(SP)以及價(jià)帶間躍遷所造成的電子能量損失峰發(fā)生了明顯的偏移和強(qiáng)弱的變化，也解釋了Nb→NbO→NbO2的初始氧化過程；另外，鈮在潮濕空氣里氧化1周，在其表面只生成很薄一層的Nb2O5氧化層。

Abstract:研究了在300℃~350℃下、變形速率為5.610-3 s-1~1.810-2 s-1和擠壓比為111條件下的熱擠壓,以及350℃下多道次的旋鍛對(duì)ZM2和ZM5鑄造合金的組織和室溫拉伸性能的影響規(guī)律。結(jié)果表明:比之鑄態(tài)組織,ZM2合金擠壓態(tài)組織細(xì)化明顯,晶粒為動(dòng)態(tài)再結(jié)晶引起的等軸細(xì)晶,室溫抗拉強(qiáng)度和延性都有顯著升高。后續(xù)旋鍛進(jìn)一步使組織得到細(xì)化,強(qiáng)度升高而延性下降。變形ZM5合金顯示出比T4處理態(tài)優(yōu)異的室溫拉伸性能。320C下,隨著擠壓速率的增大,ZM5合金的b和0.2 減小,增大;固定擠壓速率為5.610-3 s-1時(shí),升高擠壓溫度,ZM5合金的b和0.2減小,而增加。

Abstract:The effect of temperature on electric fatigue of PLZT ferroelectric ceramics were studied in this paper. The research results show that the effect of temperature on electric fatigue behaviour of PLZT is significant, the higher the temperature is, the slower the fatigue velocity. The results of temperature dependence of the dielectric constant and microstructure observation by SEM shows that fatigue mechanism was mainly domain wall pining and intergranular microcracking initated by the internal stress concentration.

Abstract:Cavitation erosions of Fe-26Mn-6Si-7Cr-1Cu and Fe-20Mn-6Si-7Cr-1Cu shape memory alloys were investigated by using an ultrasonic vibratory apparatus. It is showed that both alloys have good cavitation erosion resistance. Fe-26Mn-6Si-7Cr-1Cu alloy is more resistant to cavitation erosion than Fe-20Mn-6Si-7Cr-1Cu alloy, which is mainly attributed to the higher strain-induced martensitic transformation energy and elastic deformation energy under a localized load.

Abstract:the simulation technology of infinite volume method has been introduced, implemented in the commercial computer program MSC.SuperForge, an approach has been developed to simulate the extrusion forming of aluminium profile with its sequence number of FD-JLB8001 produced by an enterprise and it has been showed a good agreement in tendency with the experimental one. As a result of it ,the design method supported by this technology is feasible for the extrusion die used in the real production of the non-hollow profile.

Abstract:The magnetic fluid was investigated in a gas-liquid reactor made by using plasma activation and ionization reactants at atmospheric pressure. The reaction time was shorted to 2 hours by controlling discharge parameter of plasma and optimizing the thermal decomposition temperature of Fe(CO)5. The magnetic fluid has good fluidity with saturated magnetic intensity of 6.510-2T(non- concentrated). The experiments show that plasma can supply needed activation energy for gas-fluid reactants molecules to recombine and to form magnetic fluid, and it is effective method for synthesis of magnetic fluid.

Abstract:采用NH3為N源，以Ga2O3粉末為Ga源高溫氨化形成GaN粉末。用X射線衍射(XRD)、掃描電子顯微鏡(SEM)、選擇區(qū)電子衍射(SAED)對(duì)粉末進(jìn)行結(jié)構(gòu)、形貌分析。結(jié)果表明：當(dāng)Ga源溫度為850℃時(shí)得到六方纖鋅礦結(jié)構(gòu)的GaN晶體顆粒。

Abstract:米用常溫氨水水解TiOSO4過程中加入自制的表面活性劑制備了超細(xì)納米TiO2粉末，用XRD，TEM和比表面儀對(duì)不同煅燒溫度下的納米TiO2粉末結(jié)構(gòu)、粒徑大小和比表面等進(jìn)行了表征，研究了納米TiO2粉末對(duì)甲基橙的光催化降解能力。研究表明煅燒溫度在400℃～800℃時(shí)得到的納米TiO2粉末呈銳鈦礦結(jié)構(gòu)，粒徑約為5．5nm～9．6nm，比表面積高達(dá)189．45m^2/g；在850℃煅燒后所得的納米TiO2粉末為銳鈦礦與金紅石型混晶結(jié)構(gòu)；在l100℃時(shí)得到的納米TiO2粉末為金紅石型納米TiO2粉末，同時(shí)微粒出現(xiàn)團(tuán)聚且粒徑變大。光催化實(shí)驗(yàn)表明：納米TiO2粉末的光催化活性與煅燒溫度密切相關(guān)，850℃煅燒1．5h所制得的混晶結(jié)構(gòu)納米TiO2粉末表現(xiàn)出較高的光催化活性。與國(guó)產(chǎn)商品納米銳鈦礦型TiO2相比，其降解甲基橙的速率約為國(guó)產(chǎn)商品納米TiO2的1倍。

Abstract:Fabrication of semi-solid LY11 alloy by SIMA (strain-induced melt activation) technique was studied, effects of process parameters, height reduction (), isothermal temperature (Ti) and holding time, on grain size, fractal dimension and grain size distribution were investigated quantitatively. The results show that the height reduction has a great effect on microstructure evolution. Grain growth and spheroidization are promoted with increasing the isothermal temperature or elongating the holding time. Grain size has a Gaussian distribution for all samples. In the adjacent domain of peak point, counts of grains reduced and grain size increased with the decreasing of height reduction, the increasing of isothermal temperature and holding time. Pretreatment condition, i.e. cold or hot deformation, has important effects on microstructure evolution, and deformation of samples is a necessary step in SIMA process.

Abstract:采用檸檬酸sol-gel工藝制備了BaFe12O19／SiO2微晶玻璃陶瓷。結(jié)果表明，當(dāng)體系中SiO2的含量為50mol％，67mol％，F(xiàn)e／Ba處于5：1～7：1，熱處理溫度在1000℃～1100℃時(shí)可以得到單一BaFe12O19晶相或雜質(zhì)含量很少的BaFe12O19微晶玻璃陶瓷。利用計(jì)算機(jī)模式識(shí)別技術(shù)得到了結(jié)果可信的材料合成工藝參數(shù)目標(biāo)優(yōu)化區(qū)，采用模式逆映照對(duì)BaFe12O19／SiO2微晶玻璃陶瓷的合成工藝參數(shù)進(jìn)行預(yù)報(bào)和設(shè)計(jì)，并通過實(shí)驗(yàn)予以驗(yàn)證。

Abstract:Titanium based Ru-La-Sn coating anodes with various La compositions are prepared by thermal decomposition. The electrocatalytic activity of coating anode is investigated by open-circuit potential test, cyclic voltammetry test, anodic polarization curve test and alternation current impedance test. The morphology of the coating anode is studied by scanning electron microscope (SEM). It is shown that the prepared temperature has a great influence on the morphology of coating anode. The electrocatalytic ability of coating anode can be improved by doping with rare earth La. The highest activity of the coating anode is associated with the composition corresponding to 0.2 (at mole fraction) La. The increase of activity is attributed to the enhancement of active surface area.

Abstract:La1.5Mg17Ni0.5 hydrogen storage material was prepared by hydriding combustion synthesis (HCS) or mechanical alloying (MA). It was found that the hydrogen absorption properties of La1.5Mg17Ni0.5 prepared by MA are better than ones by HCS. La1.5Mg17Ni0.5 prepared by MA possesses high hydrogen storage capacity of 6.73 mass% at 523 K for less than 1 min and can absorb 4.92 mass% hydrogen at 423 K. The improvement of hydriding properties can be ascribed to the nonacrystalline formation and appearance of defects and strain during the process of mechanical alloying.

Abstract:s: ZrO2 nanoparticles supported on CNTs were prepared by adding CNTs in liquid-disposition process. The TEM photo showed that CNTs and ZrO2 nanoparticles would be separated from each other without the surfactant and be connected well when the surfactant was absorbed on the surface of CNTs. The zeta potential of the CNTs in the solution revealed that the surfactant could help them weltering the aquatic phase and enhance the stability of their dispersion. The surfactant had also functioned as bridges, which hydrophilic groups were jointed with the ZrO2 nanoparticles, and which hydrophobic chains were adhered to the surface of the carbon nanotubes, so the ZrO2 nanoparticles were supported on the surface of the carbon nanotubes through the surfactant.

Abstract:Optical hydrogen film materials based on palladium are the most important species of optical hydrogen film materials. They include Pd, Pd/Ni alloy, Pd/WO3, Pd/MoO3, Pd/TiOx and Pd/MoS2 films. This paper outlines the progress in research on optical hydrogen materials based on palladium from preparation, performance to application of these film materials. At present, the preparation of optical hydrogen film materials based on palladium is mainly using sputtering method. The performance of Pd film is the best in all optical hydrogen film materials based on palladium. However, there are some disadvantages such as foaming of Pd film surface, lamination fault sheet and decreasing of cohesion between Pd film and carrier in applications. Thereby, Pd/Ni alloy, Pd/WO3, Pd/MoO3, Pd/TiOx and Pd/MoS2 films are exploited one after another. But there are some problems in researches and applications of these film materials above-mentioned. The problems and direction in study on the materials based on palladium are put forward in discussions of the paper.

Abstract:As an important engineering alloy, monotectic alloy has attracted a great deal of attention due to its special microstructures and properties. Study progress of monotectic solidification under the conditions of microgravity, directional solidification, high undercooling and melt-spun rapid solidification was summarized and lastly, the future interesting subjects were presented.