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Abstract:The rechargeable lithium ion battery has been extensively used in mobile communication and portable instruments due to its many advantages, such as high volumetric and gravimetric energy density, long cycle life, low self-discharge rate. In addition, it is the promising candidate as the power source for electric vehicles. The first generation of negative electrode materials was pure lithium metal; the second was carbon. Nowadays extensive research is focusing on lithium alloys. In this paper, the properties of lithium metal and carbon are summarized and the development of lithium alloys is reviewed.

Abstract:Since the discovery of ordered mesoporous silica materials (MCM41) in 1992, mesoporous materials have become a hot spot in many research fields, such as catalysis, separation, adsorption, optics, electronics, etc. This paper reviews the synthesis, classification, formation mechanism, morphology control and application of mesoporous materials. Nowadays, various shaped mesostructured materials (spheres, rods, plates, spirals, ropes etc.) have been synthesized using the sol-gel, self-assembly, micro-emulsion, reverse micellar and sonochemical method etc. The mesoporous materials can be classified into silica-based and non-silica materials. Siliceous ordered mesoporous materials have been well investigated. On the other hand, less attention has been directed towards non-siliceous materials, although these could have more widespread applications. Several formation mechanisms have been proposed, including the liquid crystal templating (LCT) approach and the cooperative organization mechanism. We have prepared novel mesoporous TiO2 powders and thin films by the sonochemical and reversed mecellar methods. Their photocatalytic activity is significantly higher than those of ordinary TiO2 powders and thin films.

Abstract:The current research status of tungsten-copper composites used at high temperature in China had been expounded, which involves the fabricating technique, high temperature strength, burning erosive resistance, thermo-shock resistance and dimensional stability, etc. The properties of material have been developing as the sintering-melting method had been used. The high temperature strength was objected to the strength of tungsten skeleton. The thermo-shock resistance was subjected to the Cu-content and its well-distributed in material after melting-penetrating. And through the technologys improving, the burning erosive resistance and dimensional stability in the course of sintering had well been developed.

Abstract:Five LaNi5-type hydrogen storage alloys were prepared. Their electrodes?discharge capacity,high rate charge-discharge ability, temperature effect,crystal structure and cycling stability were investigated. The XRD results indicated that alloys examined in this work seem to be of single phase with the hexagonal CaCu5-type crystal structure. After 400 charge-discharge cycles, the same crystal structure remained, for some of oxides, for instance, Mm(OH)3 and La(OH)3;The composition of stannum or silicon stabilizes the cycle life and improves the high rate charge-discharge abilities of their electrodes;The electrochemical capacity of sample (Ml0.90Nd0.10)Ni3.60Co0.50Mn0.40Al0.18Si0.42 is above 290.72 mAh.g-1, with capacity preserving being above 70% after 400 charge-discharge cycles. Its 5C rate charge efficiency is higher than 95%,and 5C rate discharge efficiency higher than 90%. It also performs well at various operating temperatures.

Abstract:Titanium and its alloys are recognized as biocompatible materials for use in medical devices. During the last few years a new generation of Ti alloys has been created with the aim of removing vanadium as an alloying element (e.g. in Ti-6Al-4V), the potential cytotoxic effect of which has been demonstrated in several investigations. The scope of the present work is to establish the corrosion behaviors of some new titanium alloys(Ti75 alloy, TiZr alloy)in 0.9% NaCl electrolyte and in particular under biological conditions. The results showed that the new alloys generally exhibit good electrochemical behaviors in rest potential (Er), corrosion potential (Ec) and passive current density (Ip). A remarkable difference is encountered with respect to the electrolyte RPMI alone induces a favorable Ec and an increased Ip, whereas the presence of cells decreases the Ip and the Ec with respect to 0.9% NaCl and RPMI. So RPMI with or without cells is a more relevant physical electrolyte than 0.9% NaCl. The new titanium alloys show by their electrochemical behavior some advantages as compared to Ti6Al4V.

Abstract:研究了不同熱處理工藝對M963合金顯微組織和拉伸性能的影響。結(jié)果表明，經(jīng)1210℃，4h空冷固溶處理后，合金的強(qiáng)度升高，但塑性降低，尤其是在高溫(900℃)時塑性降低幅度更大：固溶處理后再進(jìn)行850℃，16h爐冷時效，強(qiáng)度進(jìn)一步提高，高溫塑性獲得恢復(fù)，但室溫塑性進(jìn)一步降低。掃描電鏡觀察發(fā)現(xiàn)：合金在l210℃，4h空冷固溶處理過程中，初生MC碳化物發(fā)生轉(zhuǎn)變，并在晶界和枝晶間析出M6C碳化物；在固溶處理后的空冷過程中，從γ溶體基體中析出細(xì)小γ相；經(jīng)850℃，16h低溫時效后，γ充分析出并長大。斷口形貌分析表明不同熱處理狀態(tài)的合金，其斷裂機(jī)制不同。根據(jù)位錯與強(qiáng)化相之間的相互作用理論討論了這種熱處理工藝對室溫和高溫拉伸性能的不同影響規(guī)律。

Abstract:在交流條件硅酸鈉溶液中利用微等離子體氧化技術(shù)合成了陶瓷涂層。通過XRD，EPMA分析了所得陶瓷涂層在不同層面上的相組成、微觀結(jié)構(gòu)及元素分布。由陶瓷涂層截面的背散射圖看出陶瓷涂層較致密、與基體結(jié)合強(qiáng)度高。XRD分析結(jié)果顯示，陶瓷涂層的最外層由莫來石及γ-Al2O3相組成，隨著向陶瓷涂層內(nèi)部的移動，莫來石的含量逐漸減少，α-Al2O3，γ-A12O3相的含量逐漸提高，而且陶瓷涂層的顏色由白色逐漸變?yōu)楹谏９柙卦谔沾赏繉拥耐鈧?cè)及陶瓷涂層與基體的交界處陶瓷涂層一側(cè)含量較多，在陶瓷涂層中間含量少。而陶瓷涂層的硬度變化也出現(xiàn)了中間高，兩側(cè)低的分布情況。

Abstract:Titanium anodes were sol-gel coated with RuO2+SnO+TiO2 containing various amounts of SnO2 by brushing, sintering and annealing. The effect of SnO2 on the microstructure; morphology and particle size of the RuO2+TiO2+SnO2/Ti coatings was examined by XRD, DTA and TEM. It was concluded that the crystal size of the coatings, which was on the scale of nanometers, was sharply reduced with increasing SnO2 content. At same time, it was shown that the coatings, which consisted mainly of a solid solution- (Ru,Sn,Ti)O2 , would remain stable and monophase during increases of the SnO2 content and the annealing temperature. The morphology of the RuO2+TiO2+SnO2 crystals in the coating was equiaxial, due largely to the presence of the SnO2.

Abstract:A model was established for high strength aluminum alloys to describe the elastic/plastic stress and strain at the crack tip fields and the effects of second phase particles with various size scales on tensile ductility. The model presents a multi-element nonlinear relation between the fatigue crack growth rate and the characteristics of constituents, dispersoids, and precipitates within the alloys. Qualitative agreement between experimental and theoretical results is obtained for the fatigue crack growth rates of 2024 Al alloy. Moreover, an optimum scheme to reduce the fatigue crack growth rates and maintain alloy strength could be approached by application of the model.

Abstract:The effect of Al2O3 on the mechanical properties and microstructure of a Ti3SiC2/ Al2O3 composite fabricated by SPS(Spark Plasma Sintering)was studied in detail. The results show that the presence of the Al2O3 improves the hardness of the Ti3SiC2 up to 10.28 GPa. While at the same time increasing the strength and fracture toughness. On the other hand, slight decreases in flexural strength and fracture toughness were observed with Al2O3 additions higher than 10vol%, as a result of agglomeration of Al2O3 particles in the composite.

Abstract:The mechanical properties, especially the elongation of the powder metallurgy (PM) Ti alloy (Ti12LC, Ti8LC) at room temperature are less than optimal due to oxygen contamination and porosity. The results of this work show that the addition of the rare earth element Nd to the PM Ti alloy resulted in improved tensile strength and elongation. The alloy containing 0.8wt% Nd has a tensile strength of 1 080MPa and an elongation of 14%. Almost the same as those of wrought material, while the processing cost was lower. The rare earth element served to scavenge oxygen from the powder surfaces thereby purifying the particle interfaces. This together with a decrease of the oxygen content of Ti substrate plus the formation of Nd oxides resulted in mechanical properties of PM Ti alloy.

Abstract:Mg(OH)2 samples with acicular or fibrous crystallizing morphology were successfully prepared by one-step reaction method under hydrothermal conditions and indexed as a hexagonal crystal system based on the results of XRD and TEM. Moreover, based on the theoretical model of anionic coordination polyhedron growth units, the growth mechanism and growth habit of the Mg(OH)2 crystals under hydrothermal conditions were first investigated in depth. It was concluded, after calculating the stability energy of the growth unit of Mg(OH)2 crystalline, that the growth direction of the growth unit of the Mg(OH)2 crystal tends to favor a one-dimensional direction, parallel to the basic layer of the Mg(OH)2 crystal. Accordingly, we propose that natural brucite with fibred crystallizing morphology was formed under hydrothermal conditions in the earth thousands years ago.

Abstract:采用懸浮熔煉法制備了Fe-Sm-Si熱電合金材料,并研究了其電學(xué)輸運(yùn)特性。實(shí)驗(yàn)表明:在Fe1-xSmxSi2合金中,Sm為n型摻雜元素,Sm輕摻雜時,試樣仍為p型,隨著Sm量的增加,試樣的Seebeck系數(shù)和功率因子都降低;Sm含量x 0.4的高Sm硅化物試樣為n型,其中,熱電性能最好的試樣成分為Fe0.6Sm0.4Si2,其電阻率在10-5W穖數(shù)量級,而Seebeck系數(shù)仍達(dá)到80 mV稫-1左右。其機(jī)理被認(rèn)為是由于Sm的4f層電子的貢獻(xiàn)。

Abstract:采用磁控濺射方法在Ni基單晶高溫合金上沉積NiCrAlY涂層，研究了真空熱處理及高溫氧化過程中，NiCrAlY涂層／Ni基單晶合金界面顯微結(jié)構(gòu)的變化及元素?cái)U(kuò)散行為。結(jié)果表明，原始涂層成分分布比較均勻，各元素分布在涂層／基體界面呈陡然變化。真空熱處理時，涂層與基體間發(fā)生互擴(kuò)散，NiCrAlY涂層的顯微結(jié)構(gòu)和相結(jié)構(gòu)發(fā)生變化：涂層／基體界面區(qū)出現(xiàn)互擴(kuò)散層(內(nèi)、外擴(kuò)散層)；出現(xiàn)γ-Ni3Al和α-Cr兩新相，導(dǎo)致涂層局部區(qū)域富Cr。1000℃氧化200h后，涂層／基體界面區(qū)的互擴(kuò)散層增厚，并且在其下的基體中出現(xiàn)擴(kuò)散影響層。Ta在涂層中擴(kuò)散時，置換了部分γ-Ni3Al相中的Al，導(dǎo)致γ相的晶格常數(shù)α0增大。

Abstract:The effect of intermetallic compound TiAl additions on the combustion synthesis of Ti3AlC2 powder from Ti, Al and C as starting powders has been studied. The experimental results show that the main phase of the combustion product is TiC with very small amount of Ti3AlC2, if the molar ratio of Ti, Al, C is equal to 3:1:2. However, Ti3AlC2 become the main phase with a small amount of TiC if a small amount of TiAl is added to the starting mixtures without changing the overall stoichiometry. The fraction of Ti3AlC2 increases with increasing additions of TiAl to the starting mixtures. The above experimental phenomena were explained through thermodynamic and kinetic analysis.

Abstract:Ordered-structure multilayer thin films were prepared on quartz substrates by the electrostatic self-assembly method. The UV-Vis-NIR spectrophotometer and the atomic force microscope (AFM) were used to characterize the films. The results indicated that order structure nanoporous TiO2 thin films showed high photocatalytic activity, and that the photocatalytic activity of heat-treated thin film was higher than that of UV irradiated film.

Abstract:Two superconducting Nb-47wt%Ti composites with island shaped Ti5wt%Nb artificial pinning centers (APC) have been made. The Ti5wt%Nb volume fractions in the composites are 10% and 20% respectively. The bulk flux pinning force curves of the APC NbTi composites at 4.2K have been studied. The results show that as the pin size is reduced Fpmax increases, and moves to higher magnetic fields. The behavior of the bulk flux pinning force curves of the Ti5wt%Nb APC NbTi composites is better than that of Nb APC NbTi composites, in that Fpmax occurs at a higher magnetic field.

Abstract:Nanocrystalline W powder and tungsten based W-Ni-Fe prealloyed powders were prepared by high-energy ball milling. The influences of: (i) milling media including cemented carbide balls (CCB) and tungsten alloy balls (TAB), (ii) rotational speed, (iii) ratio of ball to powder, and (iv) grinding time on powder characteristics were studied. The grain size, lattice deformation and morphology, of the component of particles after milled were analyzed by means of XRD, EDX and TEM. The results showed that nanocrystalline powders with size of 10nm to 80nm could be synthesized by high-energy ball milling. The percentage of nanocrystalline particles in the powders is up to 80%. The overall properties of the nanocrystalline powders prepared using the TAB milling medium was better than those prepared by CCB milling. During milling the morphology of the nanocrystalline powder evolves from spherical to granular.

Abstract:采用部分過快淬加后續(xù)晶化退火處理的方法，研究了快淬速度和晶化工藝對低稀土含量Pr0.5(FeCoZr)83.5B6粘結(jié)磁體磁性能的影響。通過實(shí)驗(yàn)對比發(fā)現(xiàn)，以26m／s速度快淬出的條屑由微晶和非晶組織組成，在700℃經(jīng)10min的晶化處理，可獲得最佳磁性能，用3．25％(質(zhì)量分?jǐn)?shù))環(huán)氧樹脂粘結(jié)的磁體磁性能為：Br=0．673T，Hci=610kA／m，Hcb=379kA／m，(BH)rn=71kJ/m^3，具有較高的內(nèi)稟矯頑力和綜合磁性能。

Abstract:結(jié)合溶膠．凝膠法和水熱法的優(yōu)點(diǎn)，將溶膠處理引入水熱法中，采用改進(jìn)的水熱法在低溫條件下合成了純鈣鈦礦結(jié)構(gòu)鈦酸鋇納米粉，并與水熱法合成產(chǎn)物進(jìn)行了適當(dāng)?shù)谋容^。通過XRD，TEM，X射線熒光光譜(XRF)，微分掃描式量熱法(DSC)以及熱重分析(TGA)分析了BaTiO3粉的結(jié)構(gòu)和組成，并初步探討了溶膠處理的作用。結(jié)果表明，采用乙酰丙酮改性的鈦酸四丁酯作為Ti源，可有效降低BaTiO3納米粉的水熱合成溫度；與常用水熱法相比，采用改進(jìn)的水熱法合成BaTiO3納米粉的溫度更低。溶膠處理過程有利于水熱合成溫度的降低。

Abstract:采用電沉積水熱合成法和高溫煅燒相結(jié)合的方法，制備了生物陶瓷涂層，研究了涂層與基體間過渡層的物相組成和界面結(jié)合強(qiáng)度。用X射線(XRD)、掃描電鏡(SEM)和粘接拉伸法進(jìn)行分析。結(jié)果表明：水熱合成后，界面結(jié)合強(qiáng)度較低，為7．04MPa。在空氣中煅燒，700℃以下時，界面出現(xiàn)極薄TiO2層，同時隨著煅燒溫度的升高，界面結(jié)合強(qiáng)度提高；800℃以上時，由于厚而疏松過渡層TiN的出現(xiàn)，界面結(jié)合強(qiáng)度反而下降。為獲取對骨生長有利的HAP β-Ca3(PO4)2雙相結(jié)構(gòu)，且界面結(jié)合強(qiáng)度高的涂層材料，將原始試樣用NaOH堿液處理并進(jìn)行電沉積水熱合成，在氬氣中900℃煅燒后，過渡層為薄且致密的TiO2層，界面結(jié)合強(qiáng)度高達(dá)22．39MPa。

Abstract:Based on boundary uncertainty theory, the service life of a powder metallurgy processed (PM) turbine disk has been analyzed. First, the general formulations are presented. The effects of the boundary uncertainty variables on PM disk life response are formulated mathematically by Taylor expansion based on the boundary uncertainty descriptions. In order to present the lifetime results (output), to a specified uncertainty a critical relative maximum deviation has been presented for the required bounds of the (input) variables. Using experimental data for the PW alloy FGH95, the boundary life of a FGH95 turbine disk has been derived. The two key bounded variables among all possible ones are chosen as an example, and the accepted jointed bounds for the two variables have been calculated to satisfy a specified fatigue life of more than 4 000 cycle number. The example shows the advantage of the boundary uncertainty than the classic probability method, and can be applied to a simple sample.

Abstract:使用共沉淀法合成了完全固溶的Al2Mo3-xWxO12系列粉體材料，用熱機(jī)械分析(TMA)壓縮法測定其熱膨脹系數(shù)，發(fā)現(xiàn)Al2Mo3-xWxO12的單斜-正交轉(zhuǎn)變溫度隨x增加而下降；通過調(diào)整材料的組成，可以控制材料的熱膨脹系數(shù)，并有望在此類材料中獲得近零或負(fù)熱膨脹材料。但是由于其結(jié)構(gòu)的各向異性，多晶陶瓷內(nèi)部存在的微裂紋使熱膨脹曲線出現(xiàn)較大的滯后環(huán)。

Abstract:A newly developed Ag5wt%C electrical contact material was fabricated using the technique of high-energy in conjunction with reductant liquid spraying chemical coating and powder metallurgy. Compared with its conventional counterparts made from traditional blending and extrusion, the new contact material has excellent physical and mechanical properties. Contact-erosion experiments were performed using an ASTM Contact Material Automatic Measuring Device. The experimental results indicated that the arc erosion resistance of the newly developed Ag5wt%C material was more than 40% higher than that of the conventionally blended counterpart. The microstructures of the AgC coating powder and the sintered-pressed sample were characterized by SEM and metallographic microscopy. The surface morphologies of the two types of Ag5wt%C contact after breaking arc melting were examined by SEM together with EDS. It was found that the melted Ag particles produced by arc thermal shock become spherical and adhered to the matrix, thereby decreasing the splattering loss of Ag. The wettability and interfacial strength between silver and graphite were much improved as a result of using the new technique. The newly developed AgC may substitute for those counterparts made from extrusion or blending as a new electrical contact material.

Abstract:為得到C／SiC復(fù)合材料的強(qiáng)連接，利用三維編織碳纖維增韌碳化硅(C／SiC)復(fù)合材料在制備過程中殘留的孔隙，采用Ni合金作為中間層在1300℃保溫45min、真空條件下對三維C／SiC復(fù)合材料用液相滲透連接方法進(jìn)行了在線連接，所施壓力為20MPa。利用掃描電鏡(SEM)及能譜初步分析了連接情況，結(jié)果表明Ni合金與C／SiC復(fù)合材料有較好的潤濕性，續(xù)沉積SiC后試樣三點(diǎn)彎曲強(qiáng)度可達(dá)σ拉=252．1MPa，σ壓=260．3MPa。

Abstract:采用溶膠-凝膠法制備出尺寸小于100nm的SnO2納米粉體，并采用XRD，TEM等手段對其進(jìn)行表征，進(jìn)而將粉體制成旁熱式氣敏元件測試其氣敏性能。結(jié)果表明，粉體的尺寸隨熱處理溫度的變化較大，所制氣敏元件具有優(yōu)良的氣敏特性，響應(yīng)恢復(fù)時間可以保證其正常使用，但功耗較大，靈敏度較高，尤其對甲烷有較高的靈敏度。

Abstract:Cu and Ni films coated on one or both sides of stainless steel substrates were produced by brush plating and electroplating techniques, respectively. The elastic moduli of Cu and Ni films with various thickness on substrates were determined using three-point bending tests. The results showed that the elastic moduli of Cu and Ni films were almost independence of film thickness and approximately the same as those of corresponding bulk materials.