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Abstract:對室溫磁致冷材料的最新進(jìn)展作了綜合報道,主要包括Gd、Gd-Si-Ge、La-Fe-(Si、Al)、Mn-As-Sb、Mn-Fe-P-As幾個化合物系列。Gd,居里溫度294K,其磁熱性能在所有純金屬中最好;Gd5Si2Ge2,居里溫度274K,在此溫度處具有巨磁熱效應(yīng);在La-Fe-Co-Si、La-Fe-Co-Al化合物中,改變Co的含量可以使化合物的居里溫度得到調(diào)整,其磁熱性能可以與Gd比擬甚至超過Gd;MnFeP0.45As0.55,居里溫度308K,具有巨磁熱效應(yīng),磁熱性能遠(yuǎn)遠(yuǎn)超過Gd。在MnAs1-xSbx化合物中,隨Sb(0

Abstract:Driving by the lower cost and better properties, the development of new positive electrode materials of Li ion battery has been paid more attention by the researchers. It is not occasional for most of positive electrode materials to have a layer type or tunnel structure. In this paper, a brief presentation on the situation of positive electrode materials was done, based on which the fundamentals to improve the positive electrode properties and to find new type materials were proposed. The necessary requirement is to have layer type structure and/or tunnel structure.

Abstract:利用旋轉(zhuǎn)銅輥急冷法和銅模鑄造法制備非晶合金薄帶或圓棒，并采用X衍射儀(XRD)、差示掃描量熱儀(DSC)和差示熱分析儀(DTA)研究了Ta，Nb和Mo對Ti50Ni20Cu25Sn5非晶合金玻璃形成能力(GFA)的影響。結(jié)果表明，Ta的添加提高了Ti50Ni20Cu25Sn5合金的GFA，Mo的添加降低了該合金的GFA，Nb的添加劑對該合金的GFA沒有明顯的影響；含Ta合金具有超過60K的寬過冷液態(tài)區(qū)(△Tx)，且其約化玻璃轉(zhuǎn)變溫度因子(Tg／Tm)大于含Nb合金和含Mo合金；采用常規(guī)銅模鑄造法制備出了直徑為lmm的(Ti0.5Ni0.2Cu0.25Sn0.05)98Ta2和(Ti0.5Ni0.2Cu0.5Sn0.05)96Ta4塊狀非晶圓棒；(Ti0.5Ni0.2Cu0.25Sn0.05)98Ta2塊狀非晶圓棒的Tg，△Tx和Tg／Tm分別為678K，84K和0．60，而(Ti0.5Ni0.2Cu0.25Sn0.05)96Ta4塊狀非晶圓棒的Tg，△Tx和Tg／Tm分別為680K，70K和0．60。

Abstract:采用Gleeble-1500熱模擬試驗機(jī)研究了Ti14阻燃鈦合金在990℃以上半固態(tài)條件下的氧化和變形行為，利用金相顯微鏡觀察變形前后及氧化的微觀組織形貌，采用X射線衍射(XRD)儀分析氧化層的組成，利用線掃描分析氧化層中元素分布。結(jié)果表明，半固態(tài)氧化溫度升高，氧化增重急劇增加，表面氧化層中只存在Ti的氧化物，不存在Cu的氧化物，表面形成5層氧化層結(jié)構(gòu)，熔融的晶界是氧向基體內(nèi)擴(kuò)散的優(yōu)先通道；Ti14合金半固態(tài)變形中，晶界、晶內(nèi)的Ti2Cu相熔融長大，形成寬化的晶界和網(wǎng)格狀結(jié)構(gòu)。

Abstract:利用Miedema參數(shù)△φ*和△nws^-1/3構(gòu)成坐標(biāo)系統(tǒng)，探討了準(zhǔn)晶合金形成規(guī)律。對已有實驗結(jié)果的31個二元、48個三元準(zhǔn)晶合金進(jìn)行了系統(tǒng)的分析，同時與利用化學(xué)鍍及電鍍方法制備的二元合金系中的47個非晶、32個晶態(tài)；三元合金系的54個非晶J2個晶態(tài)合金進(jìn)行了比較。結(jié)果表明：在給定的準(zhǔn)晶合金形成區(qū)內(nèi)，區(qū)分二元準(zhǔn)晶、非晶以及晶態(tài)合金形成的準(zhǔn)確率分別為93．5％、87．2％和72．7％；區(qū)分三元合金形成的準(zhǔn)確率分別為97．9％、87．0％和75．0％。該判據(jù)對于定性地研究及尋找新型準(zhǔn)晶合金開辟了一條新的途徑，在材料研究領(lǐng)域具有一定的理論指導(dǎo)意義。

Abstract:A simulation study on the formation properties of nano clusters in a large scale liquid Al system consisting of 400,000 atoms has been performed by a molecular dynamics method. And a cluster type index method (CTIM) has been also used to describe the structural configurations of various clusters. The results demonstrate that the icosahedron clusters (12 0 12 0) and their combines play the most important role in the microstructure transition; the nano clusters (containing up to 150 atoms) are formed by combining of some middle clusters which also are formed by combining smaller clusters; the structures of these nano clusters are very different from that of those nano clusters obtained by evaporation, ionic spray methods, and so on, the latter is formed by the multi shell crystals accumulated with an atom as the center and the surrounding atoms arranged according to octahedron configuration. These results just can be used to explain the essential distinction between the cluster configurations of Al formed by different ways.

Abstract:The valence electron structures of Ti 48Al 2X(X=Nb,Cr,V,Mn,W) (at%) intermetallics were investigated by empirical electron theory of solid and molecules(EET). The results provide a theoretical reference for the study of macroscopic properties of TiAl based alloys.

Abstract:采用銅模鑄造方法研究了Nd70-x Fe20Al10Y，(x=0，5，10，15)合金的非晶形成能力。Nd70Fe20A10和Nd60Fe20Al10Y10具有較大的非晶形成能力，在普通銅模鑄造條件下，至少可以制備出直徑為3mm的塊狀非晶。隨合金元素Y的增加，合金的熱穩(wěn)定性提高，在x=15％(原子分?jǐn)?shù)，下同)時，合金Nd55Fe20Al10Y15表現(xiàn)出明顯的玻璃轉(zhuǎn)變現(xiàn)象，玻璃轉(zhuǎn)變溫度瓦、晶化溫度Tx和過冷液相區(qū)△Tx分別為777K，830K和53K。Y的加入對Nd70-xFe20Al10Yx塊狀非晶合金的硬磁性能影響很大，矯頑力(Hc)隨Y的加入單調(diào)減少，在Y=15％時表現(xiàn)為軟磁特征。還討論了影響非晶形成能力和磁性等因素。

Abstract:利用高溫液態(tài)金屬X射線衍射儀研究了In-5％Cu合金熔體的結(jié)構(gòu)。結(jié)果表明：隨溫度由400℃升高到900℃，In-5％Cu合金熔體的平均最近鄰原子間距ri總體上呈現(xiàn)出減小的趨勢，原子配位數(shù)Ns的變化比較復(fù)雜，R1和Ns都在600℃左右出現(xiàn)轉(zhuǎn)折，原子團(tuán)簇出現(xiàn)熱收縮現(xiàn)象，其結(jié)構(gòu)在600℃附近出現(xiàn)異常變化。利用回轉(zhuǎn)振動粘度儀對In-5％Cu合金在液相線以上不同溫度進(jìn)行粘度測量的結(jié)果表明：隨溫度升高，In-5％Cu合金熔體的粘度值減小，總體上呈現(xiàn)指數(shù)變化規(guī)律，在600℃左右發(fā)生突變.粘度突變溫度與結(jié)構(gòu)突變溫度一致。

Abstract:探索了用機(jī)械合金化制備得到的金屬銻與石墨復(fù)合材料(Sbx-C1-x,x=0．1—0．4)作為鋰離子電池負(fù)極材料的電化學(xué)吸放鋰特性，發(fā)現(xiàn)球磨得到的Sbx-C1-x是由微米級Sb顆粒和C所組成的復(fù)合物。Sb0.2-C0.8的吸放鋰過程實際上是由石墨和金屬銻的吸放鋰反應(yīng)組成，首次吸鋰容量達(dá)705mAh／g，首次不可逆容量約130mAh／g。對Sb含量與Sbx-C1-x(x=0．1-0．4)電化學(xué)吸放鋰性能的關(guān)系表明Sb0.2-C0.8具有最高的首次充放電容量，而碳含量對循環(huán)穩(wěn)定性有較大的影響。

Abstract:Sonoelectrodeposition technique has been used to prepare bioactive brushite coatings on carbon/carbon composites. The effects of current density on the structures and morphology of the bioactive brushite coatings were also investigated. It is found that the coatings with plate like (021), granular like (111), and flower like(220)morphology can be fabricated by using different current densities respectively. The results show that the sizes of as deposited particles decrease with increasing current density. In addition, the mechanism of the variation of their microstructures was also discussed.

Abstract:配制了5種不同Nb，C含量的Fel4Mn5Si9Cr5Ni形狀記憶合金，測量了不同溫度和不同時間條件下固溶-時效處理的合金記憶性能，采用透射電鏡和原子力顯微鏡觀察了合金的顯微組織。結(jié)果表明NbC的析出對合金的形狀記憶性能有明顯影響，經(jīng)1200℃，10h固溶處理后的Fel4Mn5Si9Cr5Ni0．5Nb合金，經(jīng)800℃，6h時效獲得了最好的形狀記憶性能，且優(yōu)于無鈮Fel4Mn5Si9Cr5M合金經(jīng)熱機(jī)械循環(huán)訓(xùn)練的記憶性能指標(biāo)。顯微觀察表明經(jīng)過高溫固溶．中溫時效處理后的該合金中NbC粒子在合金基體時效析出，有利于合金應(yīng)力誘發(fā)細(xì)小馬氏體核心的形成。

Abstract:Graded carbonate containing apatite coatings were formed on the surface of porous titanium alkali treated or alkali and heat treated by soaking in simulated body fluid. The results indicated that a porous network structure composed of sodium titanate and titanium oxide was formed on the surfaces after the porous titanium was treated by NaOH aqueous solution. Apatite nucleation on the surface of alkali and heat treated porous titanium at early stage was homogeneous. The contents of Ca, P and O decreased while that of Ti increased with the increasing of depth and a graded structure was formed near the surface of porous titanium. The porous titanium coating with the graded apatite is expected to be applied in clinical orthopedics to enhance bone implant bonding strength.

Abstract:以YT5硬質(zhì)合金為對象，以正庚烷作為溶劑，系統(tǒng)研究了以多組元聚合物為粘結(jié)劑的注射坯樣的溶劑脫脂行為?？疾榱苏辰Y(jié)劑體系組成、脫脂溫度、脫脂時間、樣品厚度、樣品形狀對坯樣脫脂率的影響及其原因。結(jié)果表明：在3組粘結(jié)劑體系中，改進(jìn)型蠟基粘結(jié)劑溶劑脫脂速度最快，脫脂效果最好，40℃，3h條件下該粘結(jié)劑體系中能被溶劑溶解的組元的脫除率達(dá)到98％；隨脫脂溫度的升高，脫脂時間的延長，粘結(jié)劑脫除率增大；溶劑脫脂初期為擴(kuò)散控制，后期為溶解控制；粘結(jié)劑平均脫除速率與生坯表面積成正比，與生坯厚度成反比；脫脂完成后，脫脂坯邊緣和中心組織均勻一致。

Abstract:采用機(jī)械合金化制備出Mg-50％Mm(NiCoMnAl)5(質(zhì)量分?jǐn)?shù)，下同)復(fù)合材料，對其吸氫過程熱力學(xué)、動力學(xué)研究發(fā)現(xiàn)：該復(fù)合材料退火后不需要活化，在250℃、0．16MPa時的吸氫量為3．53％，α-β相區(qū)退火前后的反應(yīng)速度分別為3．13％／min，5．83％／min，具備良好的動力學(xué)性能。采用XRD衍射測試和分析機(jī)械合金化后產(chǎn)物的物相結(jié)構(gòu)，實驗證明：物相組成為Mm2Mg17和Mm(NiCoMnAl)5，混合粉末經(jīng)過機(jī)械合金化后，晶粒細(xì)化，增加了固態(tài)擴(kuò)散能力，有利于固相反應(yīng)的進(jìn)行，從而改善材料的氫化性能。

Abstract:The effects of heat treatment on the electrochemical properties and structure of La0.7Mg0.3Ni2.8Co0.5 hydrogen storage alloy were studied. It is found, by electrochemical studies, that the discharge capacity, cycle stability, high rate dischargeability (HRD), exchange current density I0 and the limiting current density IL of the alloy electrodes increase after annealing treatment. The discharge capacity of the alloy annealed at 1 123 K and the cycle life of the alloy annealed at 1 223 K are the highest and the best, respectively. In addition, the exchange current density I0 and the limiting current density IL of the alloy electrode increase with annealing at 1 123 K and then decrease with increasing annealing temperature. Meanwhile, the improvement of the high rate dischargeability (HRD) of the annealing samples is consistent with the variation of the exchange current density I0 and the limiting current density IL. Furthermore, it is found, by XRD analysis, that the peak positions and peak intensities change with increasing annealing temperature, which can be ascribed to the structural change and more homogeneous composition after annealing treatment.

Abstract:Mechanical milling behavior of Mo Si Co powders has been investigated by using XRD, SEM and TEM techniques. The mixtures of elemental molybdenum, silicon and cobalt powders with a stoichiometry of Mo5 xCoxSi3 (x=0.5,1,2) were milled in a planetary mill up to 100 hours. It was found that three kinds of powder mixtures showed the same trend in the process of mechanical milling. First, Mo (Co, Si) supersaturated solid solution was formed (Moss). High energy milling led to a remarkable expansion of the solubility of Co, Si in molybdenum. The transformation of Moss to an amorphous phase was identified after a longer time milling. In the milling process, the grain size of Mo (Co, Si) decreased gradually and the internal stress increased sharply. After 40 hour milling, the grain size was reduced to about 8 nm. The SEM analysis of milled powders showed that the particle size increased initially with milling time. After 100 hours milling, particles exhibited a spherical morphology and the particle size was reduced to about 100nm.

Abstract:研究了放電等離子體燒結(jié)(SPS)復(fù)合稀土氧化物的鉬陰極材料的二次電子發(fā)射系數(shù)、致密化、組織、結(jié)構(gòu)，對發(fā)射后的材料表面進(jìn)行了微觀組織觀察，并與常規(guī)燒結(jié)(CIP-S)方法進(jìn)行了比較。在低于常規(guī)燒結(jié)溫度180℃-280℃，保溫3min得到的復(fù)合稀土氧化物的鉬陰極材料的晶粒明顯細(xì)化，相對密度達(dá)95．6％-98．8％，因在激活發(fā)射過程中能快速在陰極表面形成高比例的稀土氧化物膜，使二次電子發(fā)射系數(shù)高于CIP—S燒結(jié)材料。但SPS燒結(jié)溫度高于l600℃，晶粒將急劇長大，二次發(fā)射系數(shù)也顯著下降.

Abstract:The composition of machinable glass ceramics in the SiO2 Al2O3 MgO K2O B2O3 Li2O ZnO F system has been studied in order to decrease their melting temperature and to increase their strength at the same time. The results show that the melting temperature and the crystallizing temperature are decreased because of adding low melting point oxides Li2O and ZnO. ZnO can expande the forming area of glass and make the glass with higher content of Li2O transparent. At the optimizing composition of SiO2, Al2O3 and MgO, cordierite is formed among mica crystals contacted each other, and the glass phase is decreased. Thus the mean free path between crystals is decreased, which results in the high strength of the machinable glass ceramic.

Abstract:The properties of Ba1-xSrxTiO3 and (V1-xCrx)2O3 double base PTC thermosensitive thick film material were studied. As (V1-xCrx)2O3 was used to replaced the expensive RuO2 and silver powders, the room temperature resistance was lowered, and non ohm contact was eliminated, not only the property of the thick film material was improved but also cost was greatly reduced. Two equations have been independently designed, according to which Ba1-xSrxTiO3 micro powders were prepared by using chemical coprecipitation. The results show that polyethylene glycol (PEG) and anhydrous ethanol can prevent granule agglomeration when making nano powders. As polyethylene glycol (PEG) with large formula weight is not poisonous and no harm to people's health, popularizing it is worth.

Abstract:采用國產(chǎn)釓制作Gd—Si—Ge合金，測量H-M曲線，計算磁熵變(-△Sm)判斷其磁熱效應(yīng)。發(fā)現(xiàn)采用商業(yè)級釓配制合金時，由于雜質(zhì)抑制了材料的一級相變，未發(fā)現(xiàn)巨磁熱效應(yīng)。經(jīng)提純后的釓盡管沒有Ames實驗室的純度高，但配制的合金具有典型的一級相變，-△Sm值基本上達(dá)到Ames實驗室報道的數(shù)據(jù)，而且居里點有所提高。