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Abstract:Ti-based bulk metallic glasses (BMGs) developed in the past decade have been reviewed in terms of their compositions, glass-forming abilities and mechanical properties. The cast defects in the BMG samples, which significantly deteriorate the mechanical properties, are discussed and summarized based on the experimental results in the literature. Some results on the cast nanostructured Ti alloys with dendritic ductile beta phase are also reviewed. A special composite microstructure, dendritic beta-Ti(M) (in micrometer size) + rod-like eutectic beta-Ti/gamma-TiCu (in nanometer size), has been obtained in the as-cast cylinders smaller than 5 mm in diameter in the Ti-Cu-Ni-Sn-Ta(Nb) systems. The Ti alloys with such composite microstructure exhibit very high strength and remarkable plasticity.

Abstract:Sr2CeO4 is not only a novel blue-emitting phosphor holding important application potential, but also a good host lattice for trivalent rare-earth activators. In recent years, more attentions were paid to the photoluminescence performance of the Sr2CeO4 doped with rare-earth. The crystal structure and spectral properties are analyzed for these phosphors. The luminescent performance of Sr2CeO4 phosphors doped with Eu3+, Sm3+, Dy3+ with tunable emission colors is reviewed. Some suggestions are proposed for the further research.

Abstract:The in-situ TiC particles reinforced Ti-matrix composites were fabricated by melting-casting. The mechanisms of crack forming and propagation were investigated during dynamic tension under static load by SEM. The results showed that microcracks easily appeared on the surface of TiC particles with stress concentration. The microcracks in advantageous orientation propagated continuously mainly by self-propagation and combination with ambient cracks among the micocracks in different position, forming the dominant crack by connection with surrounding cracks. When the crack propagation was baffled, new cracks formed on the front TiC particle in front of cracks or plastic pits formed in the matrix, and the cracks were connected with each other by propagating, so that the samples losed the stability and fractured rapidly after the cracks propagated to some extent. A model of crack forming and propagation was established according to the results.

Abstract:Magnesium matrix composite reinforced by titanium alloy (Ti-6Al-4V) particulate was fabricated by powder metallurgy route. The samples of composite were hot-extruded with an ultra-deformation ratio of 225:1. The microstructures of extruded samples were investigated using optical microscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results showed that the Ti-6Al-4V particulates were apparently elongated along the extrusion direction, thus increased its reinforcing effect on the matrix. The ultra-deformation could markedly decrease the grain sizes of the composite matrix, and greatly improve the homogeneity of microstructures when compared with a lower ratio of extrusion deformation; in addition, the oxide layers on the surface of original Mg particles were effectively broken and dispersed randomly in the vicinity of Mg-Mg interfaces. It produced an oxidedispersion-strengthening (ODS) effect, further reinforced the matrix as a kind of secondary reinforcement.

Abstract:The effects of heat input on the laser beam welding residual stress and distortion of TC4 titanium alloy were investigated by finite element analysis and experimental tests. The internal relationships of residual stress, deformation and heat input were further investigated by the metallographic section of weld. The results showed that the tensile stresses produced in the longitudinal direction of welded joints were about 700 MPa-850 MPa, but only 50 MPa-80 MPa for the transverse tensile stresses. The tensile region of longitudinal residual stress was widened and the stress peak was decreased, but the magnitude of transverse tensile stress was increased when the heat input increasing. At the same time, the angular distortion was decreased and the transverse shrinkage deformation was increased when welding at above a critical specification. As the welding specimens were fully penetrated, the effects of heat input on the angular distortion were decreased.

Abstract:The fretting wear characteristics of Titanium alloy TC11 in seawater are studied by a SRV wear machine. The effects and the lubrication media on the friction coefficient and the wear resistance are investigated. Results show that the friction coefficients turn stable with the increase of amplitude, and the volume-losses increase with the increase of the amount and amplitude of load. The wear mechanism is fatigue and peeling with grain abrasion for small amplitudes, and only grain abrasion for big amplitudes. Compared with in pure water, the friction coefficient decreases greatly even to 50% in seawater with a smaller volume-loss, exhibiting a negative interaction between corrosion and wear.

Abstract:通過不同的熱處理制度控制TMZF合金中的相組成和含量，利用XRD分析確定各種相結(jié)構(gòu)。利用納米壓入測量儀測試了不同組織結(jié)構(gòu)下的硬度和彈性模量。結(jié)果表明，當(dāng)合金中存在ω相時(shí)，合金的的硬度和彈性模量最高，隨著熱處理溫度的提高，合金中的ω相消失，代之而來的是α相，而且越接近β轉(zhuǎn)變溫度，α相含量越少，對應(yīng)的彈性模量和硬度越來越低。對于Ti—Mo—Zr-Fe合金來說壓入性能（硬度、彈性模量）與相成分之間存在著良好的匹配關(guān)系。

Abstract:研究了不同冷卻方式（水冷，空冷和爐冷）對Ti-6Al—2Zr-2V-1Mo（質(zhì)量分?jǐn)?shù)，下同）ELI（TA15 ELI）合金43mm厚板雙態(tài)組織中次生α片厚度，以及對該合金雙態(tài)組織和等軸組織損傷容限性能的影響。結(jié)果表明：水冷時(shí)α片厚約1μm，空冷時(shí)α片厚為2μm～4μm，爐冷時(shí)α片過于增厚，幾乎完全溶于等軸α相內(nèi)，形成完全等軸組織。次生α相的變化對該合金的屈服強(qiáng)度和斷裂韌性產(chǎn)生很大影響，但對疲勞裂紋擴(kuò)展速率影響不大，疲勞裂紋主要以切過或沿等軸α相界面擴(kuò)展。采用Paris（dα／dN=c（△Kn）^n公式對3種合金組織疲勞裂紋擴(kuò)展數(shù)據(jù)進(jìn)行擬合，其結(jié)果為：c=1-8×10^-8，n=3.12-3.28。

Abstract:The hydrogen storage properties of La1.8Ca0.2Mg14Ni3 were modified by mechanical ball-milling with addition of x wt%Ti (x=0,5,10). X-ray diffraction (XRD), scanning electron microscopy (SEM) and hydrogen absorption/desorption tests were carried out to study the effect of Ti. The results show that the hydrogen storage properties of La1.8Ca0.2Mg14Ni3 are remarkably improved after ball-milling with addition of small amount of Ti. For the as-cast alloy, 6 cycles of hydriding/dehydriding are needed to activate it at 613 K, and the maximum hydrogen storage capacity is around 4.12 %. After modification by ball-milling with addition of Ti, the activation behavior and the hydrogen storage capacity and the absorption/desorption kinetics are all improved. The effective desorption capacities of the alloys with x=0, 5 and 10 at 613 K are 4.69 %,4.80% and 4.83%, respectively. As x=10, the alloys can absorb more than 3% hydrogen at 373 K, and 4.81 % hydrogen (97% of the maximum hydrogen storage capacity) at 600 K within 2 min. The microstructure analysis indicated that the titanium powder on the alloy surface played the role of surface-catalysis, accelerated the hydrogen decomposition and formation, and provided more channels for hydrogen diffusion from surface, were partly transformed into amorphous structure. As a result, the hydrogen storage properties of La1.8Ca0.2Mg14Ni3 were improved

Abstract:The microstructure and hydrogen absorption and desorption properties of (V30Ti35Cr25Fe10)97.5Si2.5 alloy consisting of 75% BCC phase and 25% C14 Laves phase were investigated by X-ray, SEM and PCT measurement in this paper. The lattice parameters of BCC phase and Laves phase are 0.3021 nm (a), as well as 0.4920 nm (a) and 0.7996 nm (c), respectively. The alloy shows a good activation performance with a saturated hydrogen absorption amount up to 2.98 wt% within 5 min, and reacts with hydrogen immediately at room temperature duo to the large amount of Laves phase. The capacity of (V30Ti35Cr25Fe10)97.5Si2.5 at a given pressure agrees with the one calculated by the linear combination of its constituent phase.

Abstract:Texture was examed using XRD and low cycle fatigue property was analyzed using fatigue tester(25 kN) of MTS809A/T-type for Zr-4 alloy plate at room temperature in rolling direction and transverse direction, respectively, in this paper. Results show that the Zr-4 alloy plate has the obvious texture, and the low cycle fatigue property is better in rolling direction than in transverse direction. During the cycle deformation, only partial grains exhibited plastic deformation, where many dislocations and slip lines existed. The dislocations and slip lines in the deformed gains are denser in transverse direction than that in the rolling direction. The difference of low cycle fatigue lifes for the two samples is due to the texture in the Zr-4 alloy plate.

Abstract:在Gleeble-1500熱／力模擬機(jī)上對Zr-4合金進(jìn)行了熱壓縮試驗(yàn)，研究了其在溫度750℃-950℃和應(yīng)變速率0．005s^-1～50s^-1條件下的熱變形行為。結(jié)果表明：熱變形過程的流變應(yīng)力可用雙曲正弦本構(gòu)關(guān)系來描述，平均激活能為377．79kJ／mol。根據(jù)材料動(dòng)態(tài)模型，計(jì)算并分析了Zr-4合金的加工圖。利用加工圖確定了熱變形的流變失穩(wěn)區(qū)，并且獲得了試驗(yàn)參數(shù)范圍內(nèi)的熱變形過程的最佳工藝參數(shù)，其熱加工溫度930℃～950℃，應(yīng)變速率為0．05s^-1～0．8s^-1和10s^-1-30s^-1的2個(gè)區(qū)域。

Abstract:The wetting behavior and interracial interaction of Zr41 25Ti13.75Ni10Cu12. 5Be22. 5 molten on W were studied by the sessile drop method in high vacuum. Tungsten fiber reinforced Zr41.25Ti13.75Ni10Cu12.5Be22.5 bulk metallic glass matrix composite was fabricated by infiltration process. The results show that there is a good wettability in Zr41.25Ti13 .75Ni10Cu12.5Be22. 5 molten/W wetting system between 1053 K and 1173 K. Increase of wetting temperature resulted in the decrease of equilibrium contact angle and the increase of spreading rate and solution of W. It had little effects on the equilibrium contact angle and the equilibrium wetting time when increasing above 1173 K. Good wettability and rapid spread rate provided a wide operating space for fabricating tungsten fiber reinforced Zr41.25Ti13 75Ni10Cu12.5Be22. 5 bulk metallic glass matrix composite.

Abstract:A series of Cu-W alloys added with TiC particles were prepared by means of powder metallurgy-infiltration process. The effects of TiC addition on the microstructure and properties were investigated for the Cu-W alloys, respectively, including the static property and the vacuum breakdown property. The results showed that the hardness of W-Cu alloys increased with increasing percentage of TiC, while the electric conductivity changed slightly for TiC addition in the range of 0wt %-1.2wt%, but dramatical decreases were observed for TiC addition from 1.2wt% to 2wt%. The dielectric strength was improved and the chopping current of was decreased by TiC phase addition. The metallographic analysis of Cu-W alloys after vacuum breakdown showed that the splash of liquid copper was decreased because the TiC phase nailed on the skeletons of tungsten. The vacuum breakdown took place in interphase boundaries of copper and TiC with smaller cathode craters.

Abstract:采用機(jī)械球磨的方法制備W-1％La2O3（質(zhì)量分?jǐn)?shù)，下同）復(fù)合粉體，將粉體在1823K燒結(jié)1h制備出La2O3增強(qiáng)鎢合金。對材料的顯微組織結(jié)構(gòu)和力學(xué)性能進(jìn)行分析，結(jié)果表明：顯微組織均勻，氧化鑭主要以微小的顆粒分布在鎢-鎢界面上，鎢晶粒尺寸約為10μm～15μm：La2O3增強(qiáng)鎢合金的抗彎強(qiáng)度值475MPa，在相同密度條件下，相對純鎢燒結(jié)體提高了35％?？箯潝嗫谛蚊脖砻鳎尤胙趸|顆粒后，鎢合金的斷裂方式發(fā)生了變化，由鎢晶粒斷裂為主轉(zhuǎn)變?yōu)榇┚嗔押脱鼐嗔训幕旌?，同時(shí)分析討論了氧化鑭顆粒對合金組織性能的影響。

Abstract:The Mo-Al2O3 cermet granula films were deposited on stainless steel substrates by magnetron sputtering. The Maxwell-Garnett equivalent medium theory was used to analysis the optical constants of Mo-Al2O3 granular films. The optical constants, such as n and k, and their variations with wavelengths of from 300 nm to 800 nm were studied for the Mo-Al2O3 granular films based on the optical constants of bulk material and thin films of Mo and Al2O3. The possible reasons for the disagreement between theory and experiment were explained at the same time.

Abstract:添加Nb可提高（Nd0.9Dy0.1）9.5Fe79Co5B6.5（原子百分?jǐn)?shù)，下同）合金的非晶形成能力和快淬薄帶的晶化溫度，經(jīng)過710℃晶化處理4min后，快淬薄帶的晶粒細(xì)小均勻，從而顯著提高了快淬薄帶的磁性能。三維原子探針（Three-Dimensional Atom Probe，簡稱3DAP）分析結(jié)果表明，含Nb快淬薄帶晶化后，在晶界形成了Nb-Fe-B偏聚物，抑制了晶粒長大，細(xì)化了晶粒，進(jìn)而使晶粒間交換耦合作用增強(qiáng)，提高了合金的磁性能。

Abstract:LiFePO4/C composition cathode was synthesized by a method of in-situ carbon coating. The influence of ambient temperature on the capacity of LiFePO4/C was investigated. The Arrhenius relationship between capacity and temperature was observed by linear fit and deduced. Temperature dependence of its electrochemical characteristic was evaluated by using AC impedance spectroscopy. A new equivalent circuit based on the charge and mass transfer control process in electrode was suggested to fit the obtained AC impedance spectra. The tendency of every element in equivalent circuit obtained by Zview fitting system was used to interpret the temperature dependence of capacity for LiFePO4/C composition cathode.

Abstract:The silver base materials containing MgF2 were synthesized by powder metallurgy method. The micro-structures were studied by X-ray diffraction, metallograph and thermal analysis. The hardness, conductance, density and the friction coefficient of materials were tested. The results indicate that the Ag and MgF2 were combined in an atom range with a relative density over 98%, and the conductance of Ag samples added with CaF2 declined obviously; and the grains became thinner obviously. The hardness of material did not obviously increase and and the fi-iction coefficient to Ag and Cu did not obviously decline. In a word, the MgF2 can not be used as the additives of the solid self-lubricating materials.

Abstract:A spectroscopic measuring system was described and developed to analyze the time-varying optical spectra of electrical contacts. A simulaton system of contact life, a monochromator, a photomultiplier tube (CR114) and a four channel digital storage oscillograph are used as optical detectors, so that the precise and quick measurements can be made for the spectrums with tim. At the same time, arc voltage waveform is measured for the breaking arc at the source voltage E of 24 V and the closed contact current I of 18 A. It is shown that this system can be applied to analyse the electric arc light and voltage for spectrums, and the dynamic characteristic of the breaking arc on Ag and Ag/MeO electric contacts.

Abstract:利用固體與分子經(jīng)驗(yàn)電子理論計(jì)算了Ti2AlNb基合金中外來原子W的不同占位比引起基體電子結(jié)構(gòu)的變化，分析了價(jià)電子結(jié)構(gòu)參數(shù)nA，σ和P的變化及描述原子狀態(tài)的特征參數(shù)nT，nc,n的變化，討論了W存不同占位比情況下的價(jià)電子結(jié)構(gòu)對合金性能的影響。

Abstract:鑒于液態(tài)金屬內(nèi)部電磁力分布對電磁凈化效果的影響，提出了高頻電磁場電磁凈化技術(shù)中電磁體積力的數(shù)學(xué)模型，并具體分析了不同電力參數(shù)和實(shí)驗(yàn)參數(shù)下金屬熔體內(nèi)部電磁體積力的分布規(guī)律。研究表明，增加磁感應(yīng)強(qiáng)度能夠有效地增大熔體內(nèi)部電磁體積力，從而提高凈化效率；增加電源頻率能夠有效地改變?nèi)垠w內(nèi)部電磁體積力的分布規(guī)律，增大熔體表面的電磁體積力，但是隨著電源頻率的增大將減小電磁力在金屬內(nèi)部的作用區(qū)域，使得電磁凈化的有效作用范圍減小；在一定磁感應(yīng)強(qiáng)度下，熔體內(nèi)部某一深度處的電磁體積力隨著頻率的增加先增大后減小，當(dāng)頻率滿足f=1（4πσμχ^2）時(shí)，該處的電磁體積力取得最大值。

Abstract:利用放電等離子燒結(jié)（SPS）技術(shù)，原位制備Ti2AlC／TiAl和Ti2AlC／TiAl（Nb，B）復(fù)合材料，并研究其在900℃和1000℃的高溫氧化性能。研究發(fā)現(xiàn)，摻加Nb，B后復(fù)合材料的抗氧化性能明顯提高，1000℃氧化30h時(shí)氧化層厚度為50μm～60μm，未摻入Nb，B時(shí)其厚度約為170μm。在氧化層和復(fù)合材料交界處結(jié)構(gòu)疏松出現(xiàn)許多孔洞，Nb原子在高溫時(shí)向表面層富集使復(fù)合材料抗氧化性能提高，富Nb層的存在即可以阻擋氧原子的繼續(xù)滲入，又可以作為擴(kuò)散障，減少Kirkendall效應(yīng)；加入B后，組織明顯細(xì)化，氧化反應(yīng)初始階段氧化物的形核增多。

Abstract:TiN films were deposited onto the NiTi shape memory alloys by an arc ion plating technique. The phase identification and surface characteristics of the specimens were successively performed and tested by X-ray diffraction, scanning electron microscope and atom force microscopy. We investigated and compared compatibility and corrosion properties of NiTi alloys in vitro blood with and without TiN film. Experimental results indicated that the TiN film had improved the blood compatibility and corrosion resistance properties of NiTi alloy, and the release rate of Ni ions was reduced about one magnitude after plated TiN film; the thicker the film was, the more the properties improved.

Abstract:研究基片斜切角度對YBCO薄膜微觀結(jié)構(gòu)及超導(dǎo)電性能的影響。采用脈沖激光沉積（PLD）法在0°～6°斜切（001）SrTiO3基片上制備了具有c取向的YBCO薄膜。用XRD和TEM對薄膜微觀結(jié)構(gòu)進(jìn)行了分析，用標(biāo)準(zhǔn)四引線法測定薄膜電阻．溫度關(guān)系，從而確定薄膜的超導(dǎo)電性能。結(jié)果表明，隨斜切角度的增大，薄膜晶體質(zhì)量下降，晶格彎曲畸變程度增大，超導(dǎo)臨界轉(zhuǎn)變溫度降低，轉(zhuǎn)變寬度增大。

Abstract:以自蔓延高溫合成（SHS）的Ti2AlC粉體為原料，利用放電等離子燒結(jié)技術(shù)（SPS）研究了Ti2AlC陶瓷的燒結(jié)制備。結(jié)果表明：燒結(jié)溫度1250℃，壓力20MPa，真空燒結(jié)，保溫5min，可獲得相對密度98．6％，維氏硬度為4．3GPa的致密燒結(jié)塊體；燒結(jié)樣品的維氏硬度隨燒結(jié)溫度升高而增大，但高于1250℃后隨溫度升高反而減小，SPS方法燒結(jié)Ti2AlC陶瓷的最佳溫度為1250℃，當(dāng)燒結(jié)溫度≥1350℃時(shí)Ti2AlC分解；SEM分析表明，SPS技術(shù)燒結(jié)制備的Ti2AlC陶瓷片層尺寸隨燒結(jié)溫度的升高而增大。

Abstract:采用雙輝等離子滲金屬技術(shù)在Ti-6Al-4V表面形成均勻致密連續(xù)的滲鈮合金層。將未滲鈮和滲鈮的Ti-6Al-4V試樣分別在700℃，800℃，900℃進(jìn)行100h的高溫氧化實(shí)驗(yàn)，采用XRD，SEM及EDX對試樣在900℃氧化100h后的氧化層的相組成、截面形貌及成分分布進(jìn)行分析，初步探討Ti-6Al-4V表面滲鈮后的抗氧化性能及氧化機(jī)理。結(jié)果表明：滲鈮后的Ti-6Al-4V合金氧化速率常數(shù)降低了1個(gè)數(shù)量級，氧化激活能提高，抗氧化性能明顯改善。

Abstract:Three kinds of Ti-based PbO2 electrodes with or without SnO2+Sb2O3 interlayers were prepared by the thermal decomposition of Pb(NO3)2 solution and applied as anodes to simulate the electrolytic degradation process of phenol in aqueous solution. The experimental results show that the cell voltages for the anodes with the interlayers are lower than that without the interlayers. There are little differences in the removal rate of phenol, the COD values and the instantaneous current efficiency for the three kinds of electrode. The phenol removal rate reaches 99.2% after degradation process for 3.0 h, and the COD value declines to15.7% after degradation process for 6.5 h for the Ti/SnO2+Sb2O3/PbO2 electrode obtained by a polymeric precursor method as an anode. The instantaneous current efficiencies of electrolysis process for the three kinds of electrodes decrease with increasing the electrolysis time. The electrocatalytic activity and the accelerated lifetime were assessed by cyclic voltammetry and accelerated life tests for the three kinds of anodes. It has been found that the accelerated lifetime and electrocatalytic activity of the electrodes with SnO2+Sb2O3 interlayer are improved obviously.

Abstract:通過測定熱膨脹系數(shù)研究了熱處理工藝對NiTi合金負(fù)熱膨脹（NTE）行為的影響，并采用XRD和TEM分析對其機(jī)理進(jìn)行了探討。研究表明：360℃，130h約束時(shí)效時(shí)，隨著外加應(yīng)力的增加，NiTi合金的負(fù)熱膨脹系數(shù)先增后減，在250MPa時(shí)可獲得峰值-87．0×10^-6K^-1；時(shí)效溫度升高或高溫下時(shí)效時(shí)間延長，其NTE行為變差。母相中Ti3Ni4相定向析出所形成的內(nèi)應(yīng)力場有效控制了相變的發(fā)生并促使產(chǎn)生體積變化和雙程形狀記憶效應(yīng)，二者的聯(lián)合作用導(dǎo)致了NTE行為的產(chǎn)生。

Abstract:在高鈮TiAl基金屬間化合物的基礎(chǔ)上添加W，B，Y合金元素，熔煉了5種合金，研究了這5種合金在900℃靜止空氣中的斷續(xù)氧化行為。1000h氧化后的結(jié)果表明：含0．1％（原子分?jǐn)?shù)，下同）的Y使合金的抗氧化性有所提高，促進(jìn)合金形成了以Al2O3為主的連續(xù)致密氧化層；存高鈮含Y合金中添加W，B2種合金元素則導(dǎo)致基體發(fā)生了嚴(yán)重的內(nèi)氧化，使合金的抗氧化性能降低。

Abstract:為了改善93W-4．9Ni-2．1Fe合金的力學(xué)性能，對MA制備93W-4．9Ni-2．1Fe超細(xì)預(yù)合金粉末的燒結(jié)特性進(jìn)行了研究。采用比表面吸附法測算了預(yù)合金粉末粒度，用X射線衍射儀對粉末晶粒尺寸進(jìn)行測算，掃描電鏡觀察球磨粉末和試樣拉伸斷口的形貌，用金相顯微鏡對試樣顯微組織進(jìn)行觀察。結(jié)果表明：球磨50h后可得到粒度為0．29gm、晶粒尺寸為25．5nm、各元素分布均勻的超細(xì)93W-4．9Ni-2．1Fe預(yù)合金粉末：球磨50h的預(yù)合金粉末在1480℃燒結(jié)90min壓坯，鎢晶粒呈球形或近球形；合金抗拉強(qiáng)度、延伸率和相對密度分別為1025．4MPa，26．47％和99．45％，合金呈鎢晶粒的穿晶解理斷裂和粘結(jié)相的延性撕裂。

Abstract:Tungsten alloy scraps are considered as the second tungsten resource to recycle. The plasticity of recycled tungsten alloy has been deeply investigated in this paper. The study indicated that Ni and Fe powders of given amounts were added and mixed to the recycled powder can increase the plasticity of recycled alloy greatly. After vacuum heat treatment, the plastic behavior of recycled tungsten alloy was improved. For example, the elongation increased by about 43.4% and the cross section contraction ratio increased by about 33.9%.

Abstract:The film of La-Ni alloy was prepared by electrodepositing method in an aqueous solution. The structures of film before and after charge-discharge cycles were measured by XRD and the surface feature was observed by SEM. The electrochemical hydrogen storage performance of the film was studied by cyclic voltammetry and electrochemical impedance spectrum. The results showed that the film had a good electrochemical activity, unnecessary for an activation procedure and the maximum electrochemical capacity was 156 mAh/g.

Abstract:采用溶膠-凝膠法制備了納米晶La0.8Sr0.2FeO3。X射線衍射表明：該樣品為正交晶系鈣鈦礦結(jié)構(gòu)，其平均粒徑約為31nm。將La0.8Sr0.2FeO3納米晶粉體與聚乙烯醇PVA混合固化，然后在400℃下分別退火20min和120min。固化退火120min的元器件電阻隨乙醇濃度的增加而增加，元器件具有P型半導(dǎo)體特性。而固化退火20min的元器件電阻隨乙醇濃度的增加而減小，該元器件具有n型半導(dǎo)體特點(diǎn)。固化退火120min的La0．8Sr0．2FeO3元器件的氣敏靈敏度S=Rg／Ra在80℃下高達(dá)100，低工作溫度、高靈敏度特性對應(yīng)用有益。發(fā)現(xiàn)La0.8Sr0.2FeO3元器件的電阻R和乙醇濃度C只在較低溫區(qū)符合指數(shù)關(guān)系（R≈KC^α）。

Abstract:采用固相反應(yīng)法制備了樣品La0.67Sr0.33-xNaxMnO3（x=0．05，0．10，0．15，0．20，0．25，0．33）。通過實(shí)驗(yàn)測出了樣品的X射線衍射譜圖、M-T曲線、p-T曲線和MR-T曲線，研究了Sr位摻Na對La0.67Sr0.33MnO3的晶格結(jié)構(gòu)和磁電特性的影響。結(jié)果表明，樣品呈菱面體結(jié)構(gòu)，當(dāng)x≥0．20時(shí)，Mn^3＋／Mn^4＋〈1，體系在反鐵磁態(tài)，但實(shí)驗(yàn)中所有樣品表現(xiàn)為順磁-鐵磁相變伴隨絕緣體．金屬相變；隨X增加，巨磁電阻MR增大，Tc降低，當(dāng)x=0．33時(shí)，在室溫區(qū)獲得了很大的磁電阻MR=241％。

Abstract:采用放電等離子燒結(jié)技術(shù)（SPS）制備La-Mg-Ni儲(chǔ)氫合金，以La0.7Mg0．3Ni2.5Co0.5合金為例，探究最佳的工藝制度。結(jié)果表明：當(dāng)燒結(jié)溫度為800℃時(shí)，合金為多相結(jié)構(gòu)，包括（La，Mg）Ni3相、（La，Mg）2Ni7相、Mg2Ni相和微量的Co2Mg相；在該溫度下，合金的最大放電容量達(dá)到最大值359mAh／g，同時(shí)表現(xiàn)出最好的放電平臺(tái)特性。

Abstract:在研究鎂合金板材熔鑄及加工工藝的基礎(chǔ)上，以AZ31B鎂合金為材料，以優(yōu)化組織性能為目標(biāo)，通過控制軋制溫度、壓下制度、控溫軋制和退火制度，軋制出σb≥280MPa，σo.2≥160MPa，d≥16％的鎂合金板材，所軋制出的板材成功地得到實(shí)際應(yīng)用，并對工藝制度的合理性從理論上進(jìn)行了分析。

Abstract:The setup and principle od damper cooling tube (DCT) process to prepare the semisolid slurry of A356 aluminum alloy were introduced in different pouring temperatures. The results of measured and calculated grain size and shape factor in castings microstructure show that they are directly related to the pouring temperature, the lower the pouring temperature, the smaller the grain size and shape factor, due to the formation of stray nucleus and the cooling and stir of DCT. The semisolid slurry or billet produced by DCT processis are suitable for the semisolid processing owing to the fine grain size and spherical primary particles.

Abstract:High purity alumina/stainless steel joints were produced by activated molybdenum -manganese route using 72Ag28Cu solder. The microstructure and elemental distribution of metallized ceramic were analyzed, and the mechanism of metallization was discussed. Influences of the metallizing technologic conditions, Ni plating and subsequent annealing on the joint shear strength were investigated. The results show that both glassy phases migration and chemical reaction act the key roles for activated Mo-Mn metallizing, but sintering of the metallized layer acts the secondary role, and the main direction of glass migration is from the metallzed layer to the ceramic matrix. The maximum of the joint shear strength under the optimized conditions reaches 115 MPa, and the average strength is over 97 MPa. A thin Ni coating will prevent the metallized layer from being wetted by the solder in resulting avoiding the erosion of the layer by the solder. The annealing after plating could improve markedly the strength of the ioints.

Abstract:采用超音速電弧噴射氣霧化制粉設(shè)備制備了難固溶Ag-10Ni合金粉末。研究了粉末粒度分布、形貌及凝固組特征，并對霧化熔滴的冷卻速率及過冷度、凝固組織的凝固次序、形成機(jī)制進(jìn)行了分析。結(jié)果表明：粉末分散性好、粒度主要集中在20pm～45μm、平均粒度32μm、形貌主要為球形和近球形；粉末顆粒凝固組織為富Ag基體＋彌散分布于基體中的細(xì)Ni相＋位于芯部的大直徑初晶富Ni相，在大直徑初晶富Ni相中彌散分布析出Ag相；富Ag基體的凝固組織為樹枝晶組織，小顆粒粉末（〈20μm）枝晶間距小于0．2μm。

Abstract:The nano-crystalline CuCr25 alloys have been prepared and the breakdown experiments have been done in vacuum room. The traces of cathode spots on the surface of coarse-crystalline and nano-crystalline CuCr25 alloys have been observed using a scanning electron microscope (SEM). Experimental results show that the spot diffusion of coarse-crystalline CuCr25 cathode local iterative combustion or whole jumping move on the Cr phases with a weak voltage withstanding. But the spot diffusion of nanocrystallization of CuCr25 cathode exhibits quasi-continuous move, as one falls and another rises, due to the superior condition for electron emission, and the breakdown phase distributing on the whole cathode surface.

Abstract:采用溶碳活性很高的稀土金屬Ce和過渡金屬Fe熔煉出Ce-7％Fe（原子分?jǐn)?shù)，下同）合金，利用該合金對CVD金剛石膜進(jìn)行熱化學(xué)拋光。結(jié)果表明：Ce-7％Fe合金在592℃就可以拋光金剛石膜，比報(bào)道的稀土拋光溫度要低200℃以上；在680℃拋光3h表面粗糙度Ra值由原來的5．95μm降低到0．69μm，拋光效率高達(dá)30μm／h；SEM觀察表明，拋光使膜的表面光潔度有明顯提高；經(jīng)拉曼光譜檢測，拋光沒有對金剛石膜造成任何污染。

Abstract:采用電化學(xué)沉積法，在Cu基片上制備出了平均晶粒尺寸為3nm的納米晶α-Mn通過對其在不同溫度下真空退火，得到具有不同平均晶粒尺寸的納米晶α-Mn系列樣品。同時(shí)分析了電沉積、熱處理?xiàng)l件對結(jié)構(gòu)的影響，研究了結(jié)構(gòu)與力學(xué)性能的關(guān)系。結(jié)果表明，隨晶粒尺寸的減小，納米晶α-Mn的力學(xué)性能表現(xiàn)出正Hall—Petch關(guān)系和反Hall—Petch關(guān)系；當(dāng)晶粒小于臨界晶粒尺寸42nm時(shí)，正Hall—Petch關(guān)系轉(zhuǎn)變?yōu)榉碒all—Petch關(guān)系。