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Abstract:An advanced method of producing Al 3Ti/Al composites, self propagating high temperature synthesis (SHS) in an Al melt, is described. The mole ratio of Al/Ti in the starting powder mixture is an important parameter for that controls the microstructure of the Al 3Ti compound produced by SHS. When Al/Ti is much smaller than 3/1(the stoichiometric ratio), large needle like Al 3Ti structures will be produced. When Al/Ti is close to or larger than this value, the more favorable homogeneously distributed blocky Al 3Ti will be obtained. But if Al/Ti ratio is larger than 3 75/1, the SHS process will stop because more heat is consumed for heating up and melting the Al powder.

Abstract:Microstructural variation in sputtered Ni 9 7Cr 5 5Al 7Ti (wt%) nanocrystalline coatings during high temperature oxidation was observed. The formation of TiO 2 on sputtered Ni Cr Al Ti coatings (or the sputtered coatings removed oxide coating after 90 min oxidation) have been investigated. It was found that the formation and TiO 2 of growth are closely related to the pricipitation of Ni 3(AlTi) phase. These effects are also discussed in detail

Abstract:MoSi 2 WSi 2 powders have been synthesized by means of self propagating high temperature combustion. It was found that not only MoSi 2 WSi 2 but also Mo 5Si 3 W 5Si 3 can be synthesized by this method when suitable ratios of Mo, W and Si powders were used. As the W content increases, the adiabatic temperature of reactive system decreases, which influences the synthesis process. It is also confirmed that MoSi 2 WSi 2 and Mo 5Si 3 W 5Si 3 exist as solid solutions of [Mo (1-x) ,W x]Si 2 and [Mo (1-y) ,W y] 5Si 3, respectively.

Abstract:Nanocrystalline SnO 2 with different particle sizes has been prepared by means of hydrothermal precipitation. The resulting SnO 2 nanometer size powders, which are basically spherical in shape according to TEM, are tetragonal in structure with space group P4/mnm. Calculation shows that the crystallite size of SnO 2 increases with increase of the calcination temperature, but that the average crystal lattice distortion rate decreases with increase of crystallite size. The smaller the particle, the bigger the crystal lattice distortion and the slower the crystal growth rate. Weight loss analysis indicates the prepared SnO_2 is very slightly impure.

Abstract:Magnetic homogeneity and flux distribution in Nd Fe B magnets have been studied using a statistic method. The results show that the distribution of magnetic flux is affected by various random factors such as composition, orientational field, and magnetic flux density. The statistic results conform well to a normal Gaussian distribution. Moreover, the main factor affecting magnetic homogeneity is the orientation degree of the easy axis of the powders.

Abstract:利用鈦與Ｂ４Ｃ，石墨之間的自劃算高溫合成反應(yīng)經(jīng)普通的熔鑄工藝原位合成制備了等摩爾ＴｉＣ和增強(qiáng)的鈦基復(fù)合材料，光學(xué)金相、ＥＰＭＡ、ＴＥ幾Ｘ射線衍射的研究結(jié)果表明：存在兩 不同形狀的境強(qiáng)體，即短纖維狀ＴｉＢ晶須和等軸、近似等軸狀ＴｉＣ粒子。境強(qiáng)體與Ｔｉ基體界面潔凈，沒有明顯的界面反應(yīng)。由于境強(qiáng)體隨載荷，基體合金晶粒細(xì)化以及高密度位錯(cuò)的存在，制備鈦基復(fù)合材料的機(jī)械性能有了較大的提高。石墨的加入導(dǎo)致形成更

Abstract:A model for the temperature distribution across the interface during explosive cladding has been proposed. The model can be used to predict and analyse the microstructure of the explosively banded interface, and yields results that agree with those obtained using TEM.

Abstract:研究了鍛造Ｔｉ－４８Ａｌ－２Ｃｒ（ａｔ％）在１１８０℃熱自理音的組織演變，分析在不同溫度等溫?zé)崽幚磉M(jìn)晶粒長魘 動力學(xué)，在Ｔａ以上等溫?zé)崽幚頃r(shí)，昌粒長大迅速，其晶粒長大因子為２．４。在Ｔａ以下等溫?zé)崽幚磉M(jìn)，當(dāng)熱處理由１０ｍｉｎ不斷延長到４ｈ時(shí)，ｒ晶粒尺寸變化較小，α晶粒不斷長大。熱處理溫度越高，晶粒長大越快在１１８０℃，１２２０℃，１２６０℃和１３００℃熱處理進(jìn)晶粒長大因子分別為２．９，２．８．２．

Abstract:The effects of alkali treatment on the deposition of apatite on various titanium alloy substrates have been studied. The results show that a porous titanium dioxide hydrogel layer with negative charge forms on the substrate during alkali treatment, and the gel layer can induce apatite formation in the simulated body fluid(SBF). The pore diameter, gel thickness and the induction ability of the gel layer increase with the concentration, temperature and treating time of the alkaline solution. The induction abilities of the various substrate materials decreases according to Ti>TC4, Ti75>TiZr. It is concluded the titanium alloys treated by alkali can induce apatite formation in SBF, and are bioactive.

Abstract:配制了３種不同成分的Ａｌ－Ｃｕ－Ｍｇ－Ｆｅ－Ｎｉ－（Ｓｃ，Ｚｒ）實(shí)驗(yàn)合金，測量了合金在２００℃的時(shí)效曲線及室溫，３００℃下的拉伸性能，采用金相顯微鏡、掃描電鏡（能譜）和透射電鏡觀察了合金不同狀態(tài)下的顯微組織。結(jié)果表明：加入微量Ｓｃ和Ｚｒ后生成的一次Ａ１３（Ｓｃ，Ｚｒ）相可明顯細(xì)化基體晶粒，二次析出的Ａ１３（Ｓ質(zhì)點(diǎn)有明顯的時(shí)效硬化效果，并且有利于合金中另一強(qiáng)化相Ｓ（Ａ１２ＣｕＭｇ）更均勻析出，從而提

Abstract:Some ternary Ni Ti Nb based shape memory alloys have been prepared in the water cooled crucible of a magnetic suspension furnace under a controlled protective argon atmosphere. Anodic polarization curves of the Ni Ti Nb based shape memory alloys were measured utilizing the Montaklo Mode. The stability of the passive film was investigated in both artificial sea water (3 5%NaCl) and physiological solution (5%NaCl+0.1%H 2O 2) environments. The results show that the corrosion resistance of these alloys is excellent.

Abstract:The effects of strain rate and temperature on the tensile yield strength and elongation of titanium aluminides are studied. The alloy Ti 45Al 10Nb(at%) has a fully lamellar microstructure. The test results show that the brittle ductile transition(BDT) temperature increases with the increases of strain rate and temperature. The activation energy is 330kJ/mol, which approximates to the self diffusion activation energy of atoms in the TiAl alloy. Fractography and dislocation configuration analyses demonstrate that the brittle ductile transition of the alloy Ti 45Al 10Nb is controlled by dislocation climb.

Abstract:MgNi x(x=0 5,1 0,1 25,1 5,2 0)binary alloys have been synthesized using mechanical alloying(MA). The effect of nickel on the structure and electrochemical properties of MA Mg Ni binary alloys has been investigated. All MA MgNi x(x=1 0,1 25,1 5,2 0) alloys, except MgNi 0 5 are amorphous. The properties of the amorphous alloys are better than those of the crystallite one. As the nickel content in amorphous alloys increases, the maximum discharge capacity decreases and the average potential moves towards negative direction, but the decay of charge discharge capacity decreases.

Abstract:The corrosion rates of uranium in dry HCl air and air medium have been studied. The results show that the corrosion products are almost the same in dry HCl air as in dry air, but corrosion rates tend to be different. The main surface oxides formed are UO 2 and UO 2+x . The presence of HCl can accelerate the corrosion. Uranium reacts with hydrogen in HCl, producing uranium hydride which in return reacts with oxygen and chlorine to produce hydrogen. This reaction significantly decreases the lifetime of the uranium.

Abstract:采用自然時(shí)效、人工時(shí)效等熱處理工藝，借助航向電鏡和室溫低頻扭擺內(nèi)耗儀，研究了微量Ｃｅ，Ｌａ對高阻尼Ｚｎ－２２％Ａｌ合金時(shí)效后顯微組織和阻尼性能（內(nèi)耗）的影響。結(jié)果表明，經(jīng)水淬后８０℃溫軋的Ｚｎ－２２％Ａｌ合金在低于溫軋溫度下時(shí)效時(shí)，其阻尼性能 量Ｃｅ，Ｌａ的加入，提高了經(jīng)水淬后８０℃溫軋的Ｚｎ－２２％Ａｌ合金的阻尼性能，減緩了經(jīng)１５０℃時(shí)效后阻尼性能的降低。

Abstract:依據(jù)鋯（ＩＶ）對Ｈ２Ｏ２氧化Ｂｅｉ花青褪色的催化行為，建立了測定痕量鋯的催化動力學(xué)分析法。本法線性范圍為０～１１０ｎｇ／ｍｌ，檢測限為０．４ｎｇ／ｍｌ。除Ｃｒ（ＶＩ），Ｃｕ＾２＋和Ｆｅ＾３＋外，其余離子不影響測定。其干擾可用ＥＤＴＡ和甘露醇掩蔽消除，也可將Ｃｒ（ＶＩ）還原為Ｃｒ（Ⅲ）而消除其影響；測定了鋯青銅及合成樣品中的鋯，結(jié)果滿意。

Abstract:The processing of continuous fiber reinforced titanium alloy matrix composites (Ti MMCs) is reviewed in this paper. Special attention is placed on three processing methods: fiber foil fiber(FFF), plasma coating (PCM) and physical vapor deposition (PVD). The research progress in reinforcing fiber and matrix alloy selection is discussed. Particular attention being paid to the fibers SiC and Al 2O 3. The mechanical properties and damage evaluation of the composites are also presented.