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Abstract:This review article introduces the present research state of the Mg-B binary system, including a summary on phase species, phase transformation relationship, phase diagram and diffusion behavior between Mg and B. The key problems and significance on the research working were discussed. Finally, the potential research direction of Mg-B binary system was viewed.

Abstract:對(duì)[001]取向單晶鎳基合金進(jìn)行壓應(yīng)力處理，獲P-型筏狀結(jié)構(gòu)后，對(duì)其進(jìn)行拉伸蠕變性能測(cè)試及SEM形貌觀察，研究了P-型筏狀結(jié)構(gòu)的粗化特征及影響因素。結(jié)果表明：由于應(yīng)力場(chǎng)的差別，樣品不同位置筏狀γ＇相粗化程度及特征不同，近斷口處筏狀γ＇相扭曲且粗化程度加劇，隨離斷口距離增加，γ＇相粗化程度減弱。有限元分析認(rèn)為：外加載荷改變了水平和垂直γ基體通道中的錯(cuò)配應(yīng)力分布，并使立方γ＇相不同界面晶格發(fā)生擠壓或擴(kuò)張應(yīng)變，這可以促進(jìn)元素的互擴(kuò)散和γ＇相的定向生長(zhǎng)，是形成P-型筏狀組織的主要原因。在高溫及拉應(yīng)力作用下，P-型γ＇相端部沿垂直于應(yīng)力軸方向優(yōu)先生長(zhǎng)和相互橫向連接，并進(jìn)一步形成折疊的層狀組織。

Abstract:Based on the TF(Thomas-Fermi)equation,the interior potential boundary condition under the electric field was established.Free energies were calculated under the influence of electric field with the defined boundary for the single atom,solid solution,compound and practical alloys.It can be concluded that the monatomic free energy under the electric field was not symmetrical about zero point of the external potential.The free energy sensitivities of the three calculated elements on the side of positive electric field take turns of Al,Li,and Mg,and take turns of Al,Mg and Li on the side of negative electric field.The free energies of Al3Li compound and Al-2.14%Li solid solution exhibit different electric field symmetries and sensitivities in the electric field,and the Al-2.14%Li is more sensitive than the Al3Li at 460 K and 800 K.The free energy of solid solution Al-2.14%Li is higher than the compound Al3Li at 800 K under higher electric field,the free energy of Al3Li is lower than Al-2.14%Li at 460 K.The free energy of 1420 alloy is symmetrical about the zero external potential,consistent with its tensile properties during aging process in the electric-field.

Abstract:利用超高真空電子束蒸發(fā)法制備了可替代SiO2作為柵介質(zhì)的HfAlO膜.薄膜的化學(xué)組成為(HfO2)(Al2O3)2,900℃退火處理后仍然呈現(xiàn)非晶狀態(tài),而且表面平滑.介電常數(shù)為12.7,等效氧化物厚度2 nm,固定電荷密度4×1012cm-2,2 C柵偏壓下漏電流為0.04 m A/cm2.后退火處理能有效降低固定電荷密度和泄漏電流密度,但會(huì)造成界面SiO2的生長(zhǎng).

Abstract:在常溫常壓下，以Cu-Zn—Al合金為基體經(jīng)過(guò)簡(jiǎn)單的化學(xué)處理，在基體上成功地合成了直徑為幾十納米，長(zhǎng)度在微米量級(jí)的Si-維納米結(jié)構(gòu)。利用TEM，HREM，EDS等測(cè)試手段對(duì)Si-維納米結(jié)構(gòu)的形貌和微觀結(jié)構(gòu)進(jìn)行了表征。觀察到Cu-Zn-Al合金中存在著運(yùn)動(dòng)的“非線(xiàn)性振蕩胞區(qū)”，并且發(fā)現(xiàn)Si-維納米結(jié)構(gòu)的生長(zhǎng)和形貌與這些胞區(qū)的運(yùn)動(dòng)有著密切的關(guān)系。另外，對(duì)于Si-維納米結(jié)構(gòu)生長(zhǎng)機(jī)制進(jìn)行了初步探討。

Abstract:對(duì)鑄態(tài)及經(jīng)過(guò)熱等靜壓和均勻化處理后Ti-Al-Nb-B-W合金的微觀組織進(jìn)行了觀察和分析，研究了元素鎢對(duì)Ti—Al-Nb—B—W合金的鑄態(tài)及均勻化處理態(tài)微觀組織的影響。結(jié)果發(fā)現(xiàn)：隨著鎢含量的增加，Ti-Al-Nb-B-W合金鑄態(tài)組織中的非平衡狀態(tài)加劇，網(wǎng)狀組織和胞狀組織越來(lái)越發(fā)達(dá)；隨著鎢含量的增加，Ti-Al-Nb-B-W合金鑄態(tài)組織中的顯微縮松有增多的趨勢(shì)：在Ti—Al—Nb—B-w合金的均勻化處理過(guò)程中發(fā)生了非連續(xù)粗化，鎢不影響7等軸晶的形核位置與尺寸，但影響其形核率，隨著鎢含量的增加，7等軸晶的體積分?jǐn)?shù)有增加的趨勢(shì)；Ti-Al-Nb-B-W合金經(jīng)過(guò)均勻化處理后，隨著鎢含量的增加，其片層組織更加完善，片層間距更加細(xì)?。籘i-Al-Nb-B-W合金經(jīng)過(guò)均勻化處理后，隨著鎢含量的增加，β（B2）相析出的量更多。

Abstract:碳/碳復(fù)合材料既有良好的生物相容性,又有良好的力學(xué)性能,是一種極具潛力的新型生物材料。為提高其硬度、耐磨性,降低摩擦系數(shù),需對(duì)其表面進(jìn)行處理。本研究先利用包埋法在其表面制備SiC涂層,后利用非平衡磁控濺射技術(shù)在SiC涂層表面制備了摻鉻碳膜。通過(guò)XRD,Raman,SEM,EDAX和XPS對(duì)其結(jié)構(gòu)和形貌進(jìn)行了表征,用MM-200型環(huán)塊磨損試驗(yàn)機(jī)對(duì)膜的摩擦學(xué)性能進(jìn)行了測(cè)定。研究結(jié)果表明:摻鉻碳膜在XRD及拉曼光譜上都沒(méi)有明顯的峰,為非晶態(tài)結(jié)構(gòu)。碳原子主要為類(lèi)石墨碳。非晶態(tài)摻鉻碳膜的摩擦系數(shù)約為0.100,比碳/碳復(fù)合材料低;磨損率為0.45×10-6mm3·(Nm)-1,也比碳/碳復(fù)合材料低。

Abstract:The undercoolings of Ni-coating melt with different temperatures were in situ tested within differential scanning calorimeter facility by a flux technique. The highest undercooling obtained in this way was 411 K. The undercooling increased with the increasing of cooling rate in rang of 10 K/min-50 K/rain and melt treatment temperature at the same cooling rate, then held a constant. The relationships between crystallize rate and temperature as well as cooling rate and time were analyzed. It shows that a faster cooling rate results in a shorter time needed to finish the melt crystallization.

Abstract:以金屬硝酸鹽．尿素作為原料體系，引入了升華硫粉，通過(guò)低溫燃燒法一步合成了硫化物體系紅外響應(yīng)材料。對(duì)硝酸鹽．尿素體系的低溫燃燒過(guò)程進(jìn)行了分析，根據(jù)氧化．還原反應(yīng)的化合價(jià)理論計(jì)算了尿素燃料的理論用量。燃燒點(diǎn)火溫度為600℃，反應(yīng)時(shí)間為2min～3min，產(chǎn)物為紅色云層狀疏松多孔的納米粉末，粒徑為36nm左右。對(duì)樣品進(jìn)行XRD物相分析證明產(chǎn)物為CaS晶相，面心立方結(jié)構(gòu)。光譜分析表明：自然光可以有效激發(fā)樣品使之儲(chǔ)能：樣品在800nm～1600nm之間具有寬光譜紅外響應(yīng)效應(yīng)：紅外轉(zhuǎn)換發(fā)光峰值波長(zhǎng)位于655nm，對(duì)應(yīng)于Eu^2＋離子的4f^65d→4f^7（^8S7/2）躍遷。

Abstract:通過(guò)掃描電鏡、能譜儀、X射線(xiàn)衍射儀研究了Ag-Cu-Ti釬料中的活性元素Ti在釬料與立方氮化硼（CBN）磨粒高溫釬焊結(jié)合界面的擴(kuò)散現(xiàn)象，并運(yùn)用動(dòng)力學(xué)分析對(duì)界面反應(yīng)層的生長(zhǎng)過(guò)程及反應(yīng)激活能進(jìn)行了探討。結(jié)果表明：釬焊過(guò)程中，釬料中的活性元素Ti明顯向磨粒側(cè)擴(kuò)散偏聚并發(fā)生化學(xué)反應(yīng)，實(shí)現(xiàn)了磨粒與基體材料的牢固結(jié)合；釬焊CBN磨粒表面生成的TiB2和TiN化合物形貌接近平衡狀態(tài)下生長(zhǎng)的理想形貌；界面反應(yīng)層在釬焊溫度1153K～1193K，保溫時(shí)間5min～20min之間依據(jù)拋物線(xiàn)生長(zhǎng)法則所得擴(kuò)散激活能值表明其生長(zhǎng)過(guò)程主要受新生TiN影響。

Abstract:The corrosion behavior of titanium in hydrogen peroxide solutions was studied by measuring the titanium ions concentration using spectrophotometer.The influence of additives(K+,Ca2+,Na+,Mg2+,Cl-,HPO42-,H2PO4-)on the corrosion behavior of titanium was discussed under different pH conditions.The results indicated that Ca2+ exhibited the highest inhibition to the titanium corrosion in hydrogen peroxide solutions.However,HPO42-behaved as an accelerator to the corrosion.It was considered that the Ca2+ inhibited the titanium corrosion probably by absorbed on the titanium surface to form a thin film of CaTiO3 or CaO2.The HPO42-accelerated the titanium corrosion,however,probably by increasing the defects of surface oxide films after absorption on the titanium surface.

Abstract:Novel nanosized sulfur-containing composite cathode materials were synthesized by heating the mixture of sublimed sulfur and multi-walled carbon nanotubes(MWNTs)in certain conditions.The structure and morphology of the composite cathode materials were determined by scanning electron microscopy.The electrochemical performances of the MWNTs-sulfur composite(MSC)were characterized by charge-discharge characteristic,cyclic voltammetry and electrochemical impedance spectroscopy.The results indicate that the MSC exhibits a good rate capability,a satisfactory capacity,and acceptable cycle-life characteristics.The specific capacity was more than 700 mAh/g for the first discharge,and remained at 464 mAh/g,just 34% less after 60 cycles at room temperature.

Abstract:采用三元擴(kuò)散偶技術(shù)測(cè)定了Ni—Fe—Mo三元系1373Ni—Fe—Mo三元擴(kuò)散偶的相區(qū)成分，并對(duì)其相關(guān)系進(jìn)行了研究。K的等溫截面，借助電子探針微區(qū)成分分析方法分析了測(cè)得Ni-Fe-Mo三元擴(kuò)散偶在1373K下存在2個(gè)二元中間化合物：μ和NiMo。該三元系在1373K存在3個(gè)三相區(qū)：μ＋bcc（Mo）＋NiMo；μ＋NiMo＋fcc；bcc（Fe）＋μ＋fcc：在此溫度的擴(kuò)散偶中未發(fā)現(xiàn)三元中間化合物。

Abstract:The effects of Re on the tensile and stress-rupture properties and fracture behaviour of a single crystal superalloy containing Re were studied. Tensile specimens were prepared from this single-crystal with [001 ] orientation. The fractograph was examined by means of scanning electron microscope. The test specimens had the [001 ] growth direction parallel to the loading axis in tension. The results of the present investigation indicate that the tensile elongation of single crystal superalloy significantly decreased, but the stress-rupture elongation at high temperature increased with Re addition. The fractograph of fracture surface for the tensile specimen at room temperature showed a slide fracturing mode. The fractograph at elevated temperature showed a creep rupture mode with uneven deformation. The fractograph of fracture surface for the stress rupture specimen showed a typically ductile fracturing mode and the deformation was even.

Abstract:采用X射線(xiàn)衍射儀(XRD),掃描電子顯微鏡(SEM),維氏硬度計(jì),電子萬(wàn)能材料試驗(yàn)機(jī),動(dòng)態(tài)熱模擬機(jī)研究了稀土/MoSi2復(fù)合材料的結(jié)構(gòu)、形貌、硬度、斷裂韌性、高溫屈服強(qiáng)度、強(qiáng)韌化機(jī)理等.結(jié)果表明在MoSi2中添加適量的La2O3,可起到室溫強(qiáng)韌化和高溫強(qiáng)化作用.隨著La2O3含量的增加,樣品的硬度、斷裂韌性呈先增后減的規(guī)律,其最大值分別為10.85 GPa,7.25 MPa·m1/2.該材料的強(qiáng)化機(jī)制為細(xì)晶和優(yōu)化晶界強(qiáng)化;韌化機(jī)制為細(xì)晶韌化,裂紋偏轉(zhuǎn)、微橋接和彎曲韌化.

Abstract:采用雙層輝光等離子冶金技術(shù)在純鈦表面制備了Ti—Pd合金層。其深度大約為90μm，Pd含量呈梯度變化，并出現(xiàn)了TiPd3，TiPd2，Ti2Pd3，Ti3Pd5，TiPd，Ti4Pd等6種化合物相和Pd相。合金層在100℃的NaCl飽和溶液＋HCl溶液以及40℃的8．6％H2SO4溶液中的耐縫隙腐蝕性能優(yōu)于Ti0．2Pd合金；在室溫80％H2SO4的溶液中，腐蝕速率僅為0．682mm／a，是Ti0．2Pd合金的18．2％：在室溫30％HCl的溶液中，表面Ti—Pd的腐蝕速率僅為0．004mm／a，是Ti0．2Pd合金的12．5％。

Abstract:Using pre-alloying Ta-W-Hf powder,Ta-W-Hf bulk alloys were prepared by means of CIP(cold isostatic press),HIP(hot isostatic press)and high temperature annealing.This paper is focused on the influences of HIP and high temperature annealing on the alloy performances.The results show that high strength,high hardness and low plasticity appear for the alloy after HIP at low temperature.The elongation and section shrinking would be largely improved and the strength would be decreased after HIP at high temperature or high temperature annealing due to the oxygen element's inhomogeneous distribution in the raw material particles and remaining in the bulk after HIP to form the hidden harden cell structures without phase change in these regions.These cell structures would disappear after high temperature annealing.

Abstract:采用水溶液沉淀法成功制備了晶粒尺寸約為16．7nm的納米LaF3粉體。采用真空（10^-4Pa）壓結(jié)法（1GPa）制成納米LaF3塊體。用XRD分析測(cè)試了不同退火溫度下納米LaF3塊體的晶粒尺寸。結(jié)果表明，隨著退火溫度的升高，納米LaF3塊體的晶粒尺寸增大，從原始晶粒尺寸16．7nm長(zhǎng)大到900℃時(shí)的92．6nm。同時(shí)在不同升溫速率下測(cè)量納米LaF3塊體的DSC曲線(xiàn)，并由Kissinger方程求得其晶粒長(zhǎng)大激活能為2．01eV。

Abstract:對(duì)于磁制冷GdDyFe鑄錠復(fù)合材料和快淬得到的納米晶薄帶的結(jié)構(gòu)和磁熱效應(yīng)進(jìn)行了研究和分析。結(jié)果表明，GdDyFe鑄錠樣品和納米晶薄帶樣品的居里溫度比GdDy合金高，分別由原來(lái)的260K升高到了275K和263K，并保留了較大的磁熵變。而且?guī)追N相變溫度各不相同的鐵磁物質(zhì)復(fù)合的GdDyFe材料及其薄帶樣品的納米晶結(jié)構(gòu)使得樣品的高磁熵變溫區(qū)范圍寬化。該材料適用于埃里克森循環(huán)，為磁制冷材料的實(shí)用化帶來(lái)了希望。

Abstract:The change of microstructure and its influences on the micro-hardness and compression properties of Zr57Cu15.4Ni12.6Al10Nb5 bulk amorphous alloy with isothermal heat treatment have been studied by X-ray diffractometer, scanning electronic microscope, micro-hardness tester and compression experiment. It has been found that as the heating time increases, the crystallization temperature of the amorphous alloy will decrease. The phase decomposition and/or partial crystallization will cause the micro-hardness to increase and the compression strength to decrease rapidly, and make the fracture mode of amorphous alloys changing to that of crystalline alloys.

Abstract:Based on the SHS Reactive Flame Spray technology, TiC-TiB2 multiphase ceramic coatings were prepared in the Ti-B4C-C reactive system. Water quenching experiments were used to intercept the intermediate states of the flying particles during the spray course. The macroscopical characteristics, composition, structure, and transforming course of the intermediate-stated reactive products in different flying distance were observed, and the flying combustion course and reactive mechanism of the spray agglomerates in the oxyacetylene flame were discussed. It was showed that there were four types of intermediate-stated reactive products according to their macroscopical characteristics, which were the fully molten solid and hollow ceramic beads, the ceramic particles with molten surface whereas the un-molten core and the completely un-molten ceramic particles. The flying combustion mechanism is studied. The SHS reaction began with the melting of Ti powders. The combustion synthesis of the relatively small spray agglomerates in the core of the oxyacetylene flame was controlled by the diffusion and capillary mechanism and took place in the deflagration mode, whereas the combustion synthesis of the relatively big spray agglomerates in the periphery of the oxyacetylene flame was controlled by the ingredient melting and separating out mechanism.

Abstract:Effect of magnetic field on the shape and crystalstructure of nano MnZn ferrite precursor prepared by co-precipitation way was studied by using SEM, XRD, TEM and TG. It was shown that the morphology of nano particles would change from spheric to chain-like with increasing the magnetic field to a certain critical value. The claviform-like nano particles obtained in a magnetic field of 10 T showed the structure information of single crystal. Thermal gravity curve revealed that the activity of nano particles was reduced in a magnetic field of 10 T due to the increase of one dimension size. The mechanism of magnetic field effect on the nano particle nucleation and growth was discussed by crystal growth theory.

Abstract:The changes in phase structure and hydrogen storage properties of Ti0.9Zr0.1Mn1.5 alloy after modification by mechanical ball-milling for different time(t = 0 min,10 min,30 min,60 min)were investigated systematically.The XRD and SEM analysis show that all of the as-cast and ball-milled alloys consist of a single C14 type Laves phase with hexagonal structure.The ball-milled alloy powders appear aggregation to some extent,the particle size decreases and the activation behaviour is improved with the increase of ball-milling time for the alloy.It is found that the as-cast alloy is activated after 4 hydriding/dehydriding cycles,and its maximum hydrogen absorption capacity and effective hydrogen desorption capacity at room temperature are 209.3 ml/g and 157.6 ml/g,respectively,and the efficiency of hydrogen desorption/absorption is 75.3%.The maximum hydrogen absorption capacity and the effective hydrogen desorption capacity increase firstly then decrease at room temperature with the maximum values of 231.4 ml/g and 203.8 ml/g at t=30 min,respectively,while,its efficiency of hydrogen desorption/absorption reaches 88.1%.This shows that the overall properties of Ti0.9Zr0.1Mn1.5 alloy can be improved effectively by ball-milling.

Abstract:The mechanical properties, electrical conductivity and microstructures of 7055 aluminum alloy in various cold rolling reductions and tempers were investigated on the basis of tensile test, optical microscopy, X-ray diffraction and TEM. The results showed that the strength of 7055 alloy could be increased slightly after cold rolling and T6 aging at a smaller reduction, then decreased at a heavier rolling reduction, and always reduced with the increase of rolling reduction for the RRA temper alloy. The electrical conductivity of cold rolled 7055 alloy decreased with the increase of rolling reduction and increased for T6 and RRA temper alloys due to the lattice distortion and coarse precipitates from dislocations.

Abstract:Corrosion process of the anodized film on AZ91D magnesium alloy's surface in 3.5% NaCl aqueous solution was investigated with electrochemical impedance spectroscopy(EIS).According to the characteristic of EIS in the corrosion process,the EIS of anodized film at the initiation stage and at the propagation stage of pitting corrosion were simulated using the equivalent circuit of R(RQ)(RQ)and R(Q(R(RQ)))models,respectively.The results show that the solution resistance Rsol and the Yp of porous layer increased,and the resistance Rp of porous layer and the resistance Rb of dense layer decreased gradually.The np value almost unchanged and the Yb and nb of dense layer have no obvious regularity with prolonged of immersion time at the initiation stage of pitting corrosion.The solution resistance Rsol,the n1 value and the reaction resistance R2 in corrosion pit decreased,while the Y1 increased,the solution resistance R1,the Y2 and n2 of metal/medium interface for the anode in corrosion pit have no substantial regularity with prolonging the immersion time at the propagation stage of pitting corrosion.

Abstract:The microstructures and solidification processes of CuCr25 alloys are studied under different cooling rates in the present paper.With increasing of the cooling rate,the microstructures of CuCr25 alloys become finer and finer.When the cooling rate is up to 107K/s,nano-microstructures can be obtained.When the cooling rate is <103K/s,the solidification process of CuCr25 alloys belongs to a general solidification process;if the cooling rate is >104K/s,it belongs to the liquid phase separation process.In rapid solidification process,there is no new phase formed in CuCr25 alloys,but the solubility of Cu in Cr-rich phase and Cr in Cu-rich phase will increase.

Abstract:K417鎳基高溫合金是我國(guó)廣泛應(yīng)用于制造航空發(fā)動(dòng)機(jī)渦輪葉片的材料。研究了采用噴丸再結(jié)晶方法提高K417合金疲勞壽命的可行性。實(shí)驗(yàn)結(jié)果表明，該方法可以有效提高K417合金在650℃大氣條件下的疲勞壽命。利用掃描電鏡對(duì)試樣斷口進(jìn)行了觀察和分析，并對(duì)疲勞壽命提高機(jī)制進(jìn)行了討論。

Abstract:The effects of sintering atmospheres(vacuum,N2,Ar)on the chemical composition,saturation intensity and coercive force were studied by using X-ray diffraction,electrons back scattered images,Co-% magnetism meter and coercive force meter for the Ti(CN)base ceramets.The test results indicated that the total amount of the C,N,O and the saturation intensity were increased,but the lattice constant of binder phase was decreased in the corresponding alloy after the green compacts of Ti(CN)base ceramets were sintered in Ar,vacuum,N2,respectively.It caused a non-uniform construction if sintering in Ar and N2;even more influence in N2,resulting in a disorder coercive force.The values of Co-% magnetism and coercive force could be used as a criterion of the change of chemical composition and structure.

Abstract:The amorphous Mg2Ni0.95Sn0.05 + x wt% Ni(x=25,50,75,100,125)composites were synthesized by mechanical ball-milled.The microstructure and electrochemical properties of the composites were investigated.The microstructure analysis indicates that it is difficult to form amorphous structure when the Mg2Ni0.95Sn0.05 alloy is ball-milled without addition of Ni powder.The addition of Ni does favor the formation of amorphous structure.The electrochemical analysis indicates that the discharge capacity of as-cast Mg2Ni0.95Sn0.05 alloy is only 16 mAh/g and almost has no changes after 100 h ball milling.When the alloy with addition of Ni powder was milled its discharge capacity was greatly increased.With increasing of Ni content x,the discharge capacity increased first and then decreased,and reached the maximum of 625.6 mAh/g at x=75.For x=50 composite,the discharge capacity increased after increasing of the ball-milling time,and the maximal discharge capacity increased to 670 mAh/g at t=200 h.

Abstract:The MoS2/Ti composite films were deposited on SKD-11 steel and Si wafer by D.C, magnetron sputtering. The titanium content of the films increases with the Ti target current increasing according to EPMA. The FE-SEM result confirms that the film morphology is composed of the columns with the size of nano-meter, and more compact and hard at a higher Ti target current.

Abstract:初步研究了磁致伸縮材料TbFe1.9合金在磁場(chǎng)中凝固的取向控制。結(jié)果表明，在與重力平行的120mT磁場(chǎng)中，當(dāng)Ф16mm的合金熔體的冷卻速率為0．7℃／min時(shí)，平行于磁場(chǎng)的[111]取向?qū)⒊蔀槟毯笤嚇又械膿駜?yōu)取向。結(jié)合對(duì)凝固速率的控制，在遠(yuǎn)高于居里點(diǎn)的高溫熔體中，磁性材料的晶體生長(zhǎng)沿易軸的取向可在較弱的磁場(chǎng)中實(shí)現(xiàn)。

Abstract:為了揭示高合金化難變形GH742高溫合金鑄錠偏析規(guī)律及隨后均勻化處理過(guò)程中元素分布規(guī)律，采用微觀組織分析手段分析研究了該合金鑄態(tài)和均勻化態(tài)的顯微組織和元素的偏析情況：根據(jù)實(shí)驗(yàn)中偏析元素Nb，Ti的分布，討論了偏析指數(shù)與工藝參數(shù)和材料參數(shù)的關(guān)系。研究結(jié)果認(rèn)為：偏析指數(shù)的變化量舶在枝晶間距為80μm～120μm時(shí)減小量最大，并且在枝晶間距為120μm的條件下，合金在1160℃退火8h和16h的Nb元素的占計(jì)算值與實(shí)驗(yàn)值較符合。

Abstract:The effects of soft-contact electromagnetic casting(EMC)on the phase constitution,microstructure,mechanical property,and corrosion resistance of AZ61 magnesium alloy were investigated by comparing with the die cast ingot.Results show that the ingots made by different methods have the same phase constitution.The soft-contact EMC ingots have more fine and uniform grain structure,which improves the mechanical property of magnesium alloys.The ultimate tensile strength and elongation of soft-contact EMC specimens increase by about 30% and 27%,respectively.Moreover the fracture morphologies of soft-contact EMC specimens have more characters of gliding fracture.The potentiodynamic polarization indicates that the soft-contact EMC ingots have much better corrosion resisting property than the die cast ones because the better microstructure of soft-contact EMC improves the corrosion potential and decreases the corrosion current density.

Abstract:以高溫合金DD3為基材，利用電鍍工藝得到10μm的Pd鍍層，然后在1050℃分別做4h和14h真空熱處理，以研究Pd鍍層的阻擴(kuò)散行為。XRD和SEM／EDS的分析結(jié)果表明，電鍍后的DD3表面得到的是單一的Pd鍍層，但經(jīng)過(guò)1050℃，4h和14h的真空熱處理之后，基體中的元素如Al，Cr，Co和Ni等會(huì)通過(guò)Pd鍍層擴(kuò)散到表面，說(shuō)明Pd鍍層本身不能作為阻止基體元素?cái)U(kuò)散的涂層用于DD3的基體之上。

Abstract:Three specifications of the three-way catalysts(TWC)were prepared using an excellent Ceria-Zirconia solid solutions as oxygen storage materials to match the three vehicles made in China reaching the Eu III standard.The catalysts activities before or after aging for 100 hours were researched on the engine bench test system.The three vehicles matched with the fresh catalysts and the aging catalysts reached the Eu III standard for the Type 1 test and 80 000 kilometers durability.

Abstract:采用頂部籽晶提拉法(TSSG)從助溶劑K2W2O7中生長(zhǎng)出尺寸為25 mm×21 mm×18 mm的YbKY(WO4)2激光晶體.對(duì)原料進(jìn)行了預(yù)燒,有效地抑制了原料的揮發(fā).采用XRD,熱重-差熱分析(TG-DTA)及紅外光譜對(duì)樣品進(jìn)行了表征.實(shí)驗(yàn)表明所生長(zhǎng)的晶體為β-YbKYW.用偏光顯微鏡對(duì)晶體生長(zhǎng)條紋、生長(zhǎng)丘、生長(zhǎng)臺(tái)階和包裹物等缺陷進(jìn)行了觀察,認(rèn)為它們形成的原因是晶體生長(zhǎng)工藝不穩(wěn)定,溫度梯度過(guò)大,拉速和降溫速率過(guò)快等.

Abstract:應(yīng)用sol-gel法成功地合成了超細(xì)SrFe12O19磁粉。研究了Sr^2＋與Fe^3＋離子比、醇水比、預(yù)熱處理溫度和升溫速率對(duì)粉體的形成及其性能的影響。XRD分析表明磁粉形成了單相的鍶鐵氧體粉體；生成單相SrFe12O19粉體的Sr^2＋與Fe^3＋的離子摩爾比為1．13：12．00；粒子尺寸為43．2nm～51．8nm，接近理論單疇尺寸，使粉體有較高的矯頑力。低溫預(yù)處理、較高的醇水比和300℃-900℃之間較快的升溫速率導(dǎo)致了粒子結(jié)晶度和沿易磁化c-軸取向晶化的顯著增大，這又增大了粉體的飽和磁化強(qiáng)度。

Abstract:Several binary silver alloys, including AgSb, AgTb, AgDy, AgGa, AgTi and AgAl, have been investigated in order to develop new sheath alloys used for the BSCCO tapes. The mechanical properties of these alloys have been measured, including the tensile strength and strain. The results show that the Ag-Sb and Ag-Ti samples are the best candidate materials among the six alloys and have the highest strain and the highest tensile strength, respectively. The AgTb and AgDy alloys also have good properties while AgGa and AgAl alloys can not be used as sheathed materials due to their lower strains.

Abstract:室溫下在二甲基亞砜（DMSO）溶液中利用電解技術(shù)制備了具有金屬光澤的分散La-Co及La-Co-Ni非晶態(tài)合金粉末。合金粉末顆粒尺寸在0．1gm～20gm范圍內(nèi)。La-Co合金粉末隨著電解液中LaCl3和CoCl2濃度的變化，其La與Co的原子比由5：1變?yōu)?：5；La-Co-Ni合金粉末隨著電解液中LaCl3濃度的增加，其La的含量由5．57％（質(zhì)量分?jǐn)?shù)）增加到15．28％。因此，可以通過(guò)控制電解液濃度比的方法來(lái)調(diào)節(jié)合金粉末中各金屬的含量。對(duì)合金粉末壓片樣品進(jìn)行線(xiàn)性?huà)呙柩h(huán)伏安試驗(yàn)研究，得出La-Co合金粉末中La^3＋，Co^2＋的還原峰電位分別為2．68V，-1．83V；La，Co的氧化峰電位為-1．10V，-0.42V。La-Co-Ni合金粉末中Ni^2＋，Co^2＋共還原電位在-1．49V～-1．70V范圍，Ni，Co的共氧化電位在-0.65V～0.51V范圍。