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Abstract:TFDC (Thomas-Fermi-Dirac-Cheng) electron theory is applied to analyzing the characteristics of the electrons inside the double layer of the nanometer composite thin films. This paper proposes the new mechanism about the high capacity in both theoretical analysis and experimental measurement.

Abstract:基于微觀相場動(dòng)力學(xué)模型，編制了包含共格畸變能的二元立方合金沉淀過程微觀組織演化的計(jì)算機(jī)模擬程序，開展了不同共格畸變能作用下，溶質(zhì)濃度為20at％的二元鎳基合金的粗化機(jī)制的計(jì)算機(jī)模擬。研究發(fā)現(xiàn)：共格畸變能為零時(shí)，粗化遵循LSW機(jī)制，僅僅由顆粒的尺寸大小決定：隨著共格畸變能的增大，粗化過程遵循混合機(jī)制，由沉淀顆粒的大小和位向（顆粒間的相對(duì)位置）共同決定；當(dāng)共格畸變?cè)龃蟮揭欢ǔ潭葧r(shí)，粗化過程純粹由顆粒間的位向決定，處于彈性“軟”方向上的顆粒優(yōu)先長大，而處于彈性“軟”方向外的顆粒將消失掉。

Abstract:The tensile stress-strain characteristics of Ag and AgMn alloy-sheathed Bi-2223 tapes have been studied, and the effects of sheath material, filament number and Ag/core ratio on the critical current of Bi-2223 tapes have been compared. Using the Ag-alloy tube as an outer sheath of Bi-2223 tapes can increase the residual thermal compressive stresses in the filaments, avoid a wavy interface between the Ag sheath and oxide core, and limit the stress concentrations induced by the interface inhomogeneity, thus the micro-crack will be formed at higher stress levels and the tensile strain tolerances of tapes can be improved remarkably. In this study, the critical tensile stress can be improved from 62 MPa to 124 MPa, and the irreversible tensile strain can be improved from 0.31% to 0.52% by using the AgMn-alloy as an outer sheath instead of pure Ag in 37-filamentary tapes. In addition, we found that Bi-2223 tapes can tolerate higher tensile strain level by increasing the filament number and Ag/core ration.

Abstract:The critical conditions of solidification orientation for Solidification of giant magnetostrictive materials R-Fe alloy in a magnetic field have been investigated. The experiment results show that suppressing the turbulence in melt is a key factor in texturing the magnetic materials. In solidification course, the turbulent degree in melt is dominated by the cooling rate, and a modified Ra^m number is used to simulate the state of turbulence at various cooling rates. While the value of the critical Ra^c number in magnetic field is large than that of the modified Ra^m number in melt, the temperature oscillations in melt will be restrained, and the texture along the easy magnetic axis will be dominant in the sample. Therefore the critical conditions of effective orienting action for magnetic materials by solidification in a magnetic field can be definite as the rate of the critical Ra^c number in a magnetic field to Ra^m number in melt is close to 1.

Abstract:采用傳統(tǒng)陶瓷工藝制備了錳摻雜0.8(Na0.5Bi0.5)TiO3-0.1BaTiO3-0.1(K0.5Bi0.5)TiO3(BNT-B-BKT)無鉛壓電陶瓷材料,研究了材料的介電、壓電和鐵電性能.發(fā)現(xiàn)錳摻雜大幅降低了0.8(Na0.5Bi0.5)TiO3-0.1BaTiO3-0.1(K0.5Bi0.5)TiO3陶瓷的電導(dǎo)率和矯頑場,最佳摻雜量為0.1%(質(zhì)量分?jǐn)?shù)),該配方的最佳燒結(jié)溫度為1150℃.這一溫度下燒結(jié)所得樣品在130℃時(shí)的電導(dǎo)率僅為1.36×10-1Ω-1cm-1,約為摻雜前的1/40,矯頑場Ec僅為2.78 kV/mm,剩余極化強(qiáng)度Pr為38μC/cm2,壓電系數(shù)d33達(dá)到143 pC/N.

Abstract:Using Ti, Al and C powders as starting materials, the effect of intermetallic compound TiAl3 addition on the combustion synthesis of Ti3AlC has been studied. The experiment results show that the main phase of the combustion product involves Ti2AlC and TiC without Ti3AlC, if the molar ratio of Ti, Al, C is equal to 3:1:1. However, the product Ti3AlC is produced by combustion synthesis if a small amount of TiAl3 is added to the starting mixtures without changing the overall stoichiometry. The Ti3AlC becomes the main phase in the final product upon adding 23.5% TiAl3 (mass fraction) in the raw mixtures. The amount of Ti3AlC increases with increasing of addition of TiAl3 in the raw mixtures. The above experimental phenomena were explained through thermodynamic and kinetic analysis.

Abstract:對(duì)Cu-7．9％Co包晶合金不同定向凝固速率下的凝固組織進(jìn)行了研究。結(jié)果表明：在定向凝固速率1μm／s～100μm／s下，隨凝固速率的提高，初生α-Co相體積分?jǐn)?shù)減少，使形態(tài)從定向生長的枝晶轉(zhuǎn)變?yōu)榈容S枝晶，相應(yīng)地β-Cu包晶相的生長界面形態(tài)由平界面轉(zhuǎn)變?yōu)橹罱缑?。利用最高界面生長溫度假設(shè)，計(jì)算得到了凝固速率在0．55μm／s～5000μm／s范圍內(nèi)α-Co相領(lǐng)先于β-Cu相生長，與實(shí)驗(yàn)結(jié)果較為吻合；并當(dāng)凝固速率大于5000μm／s時(shí)，β-Cu相的凝固界面生長溫度高于α-Co而成為領(lǐng)先相，可以不通過包晶反應(yīng)直接從熔體中凝固析出。

Abstract:In this paper the galvanic corrosion behavior laws of AM50 magnesium alloy coupled with different alloys in Beijing atmospheric environment were investigated. The results show that the magnesium alloys act as anode. The atmospheric galvanic effect of magnesium alloys coupled with LY12 aluminium alloy is the least in all of testing cathode alloys. The atmospheric galvanic effects in Beijing compared with other cities indicate that atmospheric environment is the most important factor. The atmospheric galvanic effects for magnesium alloys are affected by cathode alloy, testing time, sample size and environment condition. SEM, XRD and optical microscope were used to investigate the morphology changes on the surface of AM50 magnesium alloy.

Abstract:采用旋鑄急冷工藝在大氣環(huán)境中制備出了（Ni0.75Fe0.25）78Si10B12非晶合金帶材。X射線衍射（XRD）分析表明樣品為完全非晶。用Diamond TG／DTA差熱分析儀在高純氬氣保護(hù)下測量了非晶薄帶的熱穩(wěn)定性參數(shù)Tg，Txi，Tpi并分析其晶化行為，加熱速度分別為10K／min，20K／min，30K／min，40K／min。（Ni0.75Fe0.25）78Si10B12非晶合金的Tg，Txi，Tpi均隨加熱速率的增加而增加，說明其玻璃轉(zhuǎn)變和晶化行為均有動(dòng)力學(xué)效應(yīng)。分別用Kissinger法和Ozawa法計(jì)算該非晶合金的晶化激活能，2種方法的計(jì)算結(jié)果是一致的。對(duì)試樣在通高純氬氣保護(hù)下，進(jìn)行等溫（695K，715K，745K，765K，保溫60min）退火處理，利用XRD分析了非晶合金等溫晶化時(shí)相轉(zhuǎn)變及組織轉(zhuǎn)變。合金在715K和745K溫度退火時(shí)，在非晶基體上析出了單一的γ-（Fe，Ni）固溶體，平均晶粒尺寸分別約為10.3nm和18．5nm，765K退火處理后的結(jié)晶相為γ-（Fe，Ni），F(xiàn)e2Si，Ni2Si和Fe3B，平均晶粒尺寸約29．6nm。

Abstract:通過化學(xué)鍍方法在玻璃纖維表面沉積了Ni-Fe-W-P合金,所用鍍液經(jīng)鈀鹽法測試,穩(wěn)定性很好,所得鍍合金玻璃纖維經(jīng)熱震實(shí)驗(yàn)后表面無鼓泡、起皮現(xiàn)象,說明鍍層的抗沖擊強(qiáng)度高,結(jié)合力良好。利用掃描電鏡觀察了鍍層的表面形貌,同時(shí)使用X射線能譜儀對(duì)鍍層成分含量進(jìn)行了分析,鍍層中鎢的質(zhì)量分?jǐn)?shù)最大可達(dá)22.2%,并得出了硫酸鎳、硫酸亞鐵、鎢酸鈉濃度對(duì)鍍層導(dǎo)電性能的影響情況,制備的鍍合金玻璃纖維電阻率為28.3×10-3?·cm。對(duì)玻璃纖維合金層進(jìn)行的XRD分析表明,在鍍態(tài)下為非晶態(tài)結(jié)構(gòu),玻璃纖維熱穩(wěn)定性好,適宜的工作溫度范圍低于250oC。最后對(duì)所得Ni-Fe-W-P合金玻璃纖維的電磁參數(shù)進(jìn)行了初步的測定與分析,所得鍍金屬玻璃纖維的磁損耗為0.05475;介電損耗為2.18424,鍍層合金為軟磁性材料。

Abstract:Through tensile test, tensile-unload test and SEM observation, the effects of loading rate on fracture mechanism of TiAl-based alloys with fully lamellar and duplex microstructures were investigated. The result reveals that when the rate is lower, microcrack density is larger and microcracks have sufficient time to initiate along many grain boundaries or lamellar interface, and propagate basically along interlamellar within the grain. There are no river patterns on the fracture surface. A majority of the fracture surface belongs to interlamellar fracture, and grain structure is not obvious on fracture surface, such case effects on the mechanical properties are dominant. While the microcracks have no time to initiate and propagate in the case of high loading rate, many river patterns come into being in the course of fracture, and we can also find the grain structure no longer obvious on the fracture surface. Because many microcracks initiate ahead, the size of fracture facet is smaller, so the effects are much less obvious, in this case.

Abstract:Nitrogen-doped TiO2 was prepared by Ti(SO4)2 solution reacting with NH3 aqueous solution. The optical absorption edge of nitrogen-doped TiO2 shifted 20 nm toward the infrared and also absorbs the visible light from 400 nm to 530 nm compared with undoped TiO2.Band gap of undoped TiO2 was 3.24 eV and nitrogen-doped TiO2 was 3.14 eV. X-ray photoelectron spectroscopy(XPS) measurements show that the nitrogen in N-doped TiO2 is in dissociative interstitial state. That the new absorption band at 400 nm ~530 nm is induced by oxygen vacancies in N-doped TiO2, which exhibits a narrow band close to the conduction band. The MTT assay was used for detecting the activity of N-doped TiO2 on the growth of leukemic HL60 in vitro. The results indicate that N-doped TiO2 can improve the efficiency of destructing leukemic HL60 cells no matter there is or not visible-light irradiation.

Abstract:Quintary Zr52.5Cu17.9Ni14.6Al10Ti5 bulk amorphous alloys were synthesized with industrial sponge zirconium. The wedge-shaped samples added with Sc were prepared. The mechanism of Sc increaseing the GFA of the ahoy was analyzed by means of X-ray diffraction. SEM and Energy Spectrum Analysis. The results showed that adding Sc to the alloy could cause the transformation of phase structure and the composition of the pre-separation phase in the transitional region of the quintary alloy. Sc with great capacity of deoxidization could decrease the existence of Zirconium oxide or Zirconium/oxygen clusters in the alloy, and eliminate heterogeneous nucleants in the melt. Consequently. adding Sc to the alloy could increase the GFA of the quintary alloy.

Abstract:Spontaneous Al2O3 reinforced TiAl composite was prepared by reaction synthesis with hot pressing. The effect of doping Nb2O5 on microstructure was investigated as well. Adopting DTA, XRD analysis, their reaction courses were analysed and discussed. SEM, XRD, metallography analysis and other test showed that it is niobium oxide improved aluminium thermal reaction and released much higher energy which made the composite could be sintered under lower temperature. Meanwhile, the doping of Nb2O5 has a function to control and alter the proportion of the matrix (TiAl: Ti3Al)phase, strengthen the forming of spontaneous alumina composition in the material, and produce greater influence on the microstructure.

Abstract:The rolling Deformation and strengthening mechanism of typical wrought magnesium alloy AZ31, AZ31(0.8%Ce) and AZ31(0.8%Nd) were studied. The microstructures, mechanical properties and the effects of rare earth Ce and Nd on AZ31 alloy were investigated. The results show that the work hardening of experimental alloys is serious and brittle breaking happen easily. Doping of rare earth can improve both the strength and ductility of AZ31 Alloy. The refine grain strengthening, working hardening and rare earth phase strengthening are the main strengthening mechanism of A231 series alloy.

Abstract:In this paper, the relation between the resistance and the temperature of Stainless Steel (SS) and its fabric are studied. It is found that the resistance of Stainless Steel (SS) fiber has a positive linear relationship with temperature, and that of SS fabric has a negative linear relationship with temperature within a definite range. The textile structure is useful to increase the sensitivity and accuracy of the temperature sensing. The main mechanism of the fabric sensing has been deduced to be the change of the contact resistance between yarns during temperature changing.

Abstract:采用纖維推出法測量了SiCf／Ti-6Al-4V復(fù)合材料的界面剪切強(qiáng)度。結(jié)果表明，熱壓態(tài)碳涂層和未涂層纖維與基體的界面剪切強(qiáng)度分別為118．2MPa和230MPa，界面脫粘發(fā)生在碳涂層或纖維與界面反應(yīng)層之間。500℃，600℃和800℃退火處理后，界面剪切強(qiáng)度均低于熱壓態(tài)的強(qiáng)度，隨退火時(shí)間的增加，500℃處理后的界面剪切強(qiáng)度呈下降趨勢(shì)，600℃和800℃處理后呈微弱上升趨勢(shì)，而且800℃處理后，界面脫粘可發(fā)生在基體／界面反應(yīng)層和碳涂層或纖維／界面反應(yīng)產(chǎn)層2個(gè)界面。

Abstract:A novel type of self-sharpen tungsten alloy (SSTA) was fabricated with the design of matrix elements. The microstructures and properties of the SSTAs were studied. The results show that the dynamic compression strength of the SSTAs are higher than that of the conventional tungsten alloys (WHAs), and the failures of SSTAs appear as the form of splits along the loading direction without any visible plastic deformation under the condition of dynamic compression. The special failure mechanism is beneficial to the improvement of the SSTA ability to self-sharpen during ballistic tests.

Abstract:The effect of applied anodic bias upon the photoelectrocatalytic degradation of methylene blue under ultraviolet illumination on nanoporous undoped TiO2/Ti electrode was studied in the present paper. The influence of doping different transition metal ions in TiO2/Ti on the degradation of methylene blue was also investigated.. The degradation degree was characterized with decolorization of methlylene blue. The results indicate that the degradation efficiency increases with increasing of the applied anodic bias up to 3.5 V, then decreases gradually. Doping TiO2 with Mn2+ and Cr3+ will enhance the efficiency of photoelectrocatalytic, while depositing Ni2+ on the TiO2 film shows a decrease of photoelectrocatalytic efficiency. The above metioned phenomena are attributed to ionic radii and the electron work functions values of the differently doped ions.

Abstract:The effect of magnesium on thermodynamics and kinetics of oxidation of melted Al-Mg-Si alloy, the microstructure and properties of Al2O3/Al-Mg-Si composites were studied in this paper. It has been found that magnesium promotes nucleating and growing of Al2O3 in Al2O3/Al composite by analysis of thermodynamics and kinetics. The properties of Al2O3/Al composite were improved by microstructure refining due to spinel (MgAl2O4) decomposing. But too high or too low content of Mg in the alloy is disadvantageous for Al2O3 nucleating and growth.

Abstract:利用碳熱還原法,通過兩步反應(yīng)合成了LiVPO4F/C復(fù)合正極材料.主要研究了球磨、碳含量和電解液對(duì)樣品結(jié)構(gòu)和電化學(xué)性能的影響.結(jié)果表明球磨2 h在750℃下能合成純的LiVPO4F產(chǎn)品,剩余碳的存在使LiVPO4F的粒徑減小且分布較為均勻,同時(shí)提高了顆粒之間的導(dǎo)電性.對(duì)樣品進(jìn)行電化學(xué)性能測試表明,含碳量為1.83%的LiVPO4F/C的樣品比容量和循環(huán)性能都得到顯著改善;合適的電解液可以明顯提高樣品LiVPO4F的電化學(xué)性能.含碳量為1.83%的LiVPO4F/C的復(fù)合材料以1 mol.L-1LiPF6/EC+EMC+DMC(體積比1∶1∶1)為電解液,在0.2 C的倍率下放電時(shí),其首次放電容量為119 mAh.g-1,放電平臺(tái)在4.2 V左右(vs.Li),循環(huán)30次后比容量為89 mAh.g-1.

Abstract:Efficient process of explosion synthesis has been established for the synthesis of anatase and rutile as well as their mixtures. The powders were characterized by X-ray diffraction (XRD), BET surface areas. The results showed that the as-prepared grain size was from 8.4 nm to 50 nm, and the maximal SBET was 107.8 m2/g, the average pore size distribution of the sample was 6 nm to 15 nm. With increasing the proportion of detonator, the size of TiO2 crystallite increased, the BET surface areas decreased, the pore size increased, meanwhile the contents of rutile increased and anatase decreased.

Abstract:將一定配比的LiOH·H2O,V2O5,H3PO4和蔗糖(C12H22O11)通過球磨均勻混合,烘干后埋入石墨粉中,在功率為800W的家用微波爐中高火加熱15 min,通過碳熱還原合成Li3V2(PO4)3.用X射線衍射和掃描電鏡對(duì)材料的結(jié)構(gòu)和形貌進(jìn)行了表征.充放電測試表明,在電壓范圍為3V～4.3V和3V～4.8v時(shí),Li3V2(PO4)3正極材料具有較高的比容量、優(yōu)良的循環(huán)性能和倍率特性.在電壓范圍為1.5 V～4.8 V時(shí),Li3V2(PO4)3正極材料具有很高的比容量,但循環(huán)性能較差.該材料有望用于鋰離子電池部分取代昂貴的LiCoO2,也可望應(yīng)用于動(dòng)力型和儲(chǔ)能型鋰離子電池.

Abstract:The diffusion characteristics of Ga in SiO2 films and at the interface of SiO2-Si is characterized and analyzed by means of SIMS, SRP and AFM respectively. The results indicate that the new element Ga born of pyroreaction of H2 and Ga2O3 is absorbed rapidly by SiO2 films and reach the interface of SiO2-Si, its absorb-export flux is directly proportional to doping time under a certain condition; Ga diffuses effectively in the Si body according to solid-solid diffusion principle at the interface of SiO2-Si and depend on the higher solubility in Si; by well combination of the too above mentioned, Ga diffused into the Si body through ideal surface and gained diffused result of high homogeneity and high repeatability.

Abstract:研究了原位加熱濺射的NiTi形狀記憶合金薄膜的結(jié)構(gòu)，討論了制備工藝及織構(gòu)對(duì)薄膜相變特征的影響，采用電阻法及X射線衍射分析了薄膜的結(jié)構(gòu)及相變過程，確定了最適合于微器件的濺射工藝。結(jié)果發(fā)現(xiàn)：濺射時(shí)采用原位加熱可直接獲得具有織構(gòu)的晶化薄膜，提高濺射功率將使薄膜的相變溫度升高。

Abstract:用非自耗真空電弧爐制備LaMn2Ge2合金,采用X射線衍射研究了合金的結(jié)構(gòu),LaMn2Ge2在常溫下具有ThCr2Si2-型晶體結(jié)構(gòu),空間群為I4/mmm.利用振動(dòng)樣品磁強(qiáng)計(jì)測量合金的磁性能,根據(jù)升降溫的磁化曲線所確定的合金發(fā)生反鐵磁-鐵磁相變溫度有4.3 K的滯后,居里溫度約320 K,具有一級(jí)相變的典型特征.通過不同溫度的磁化曲線結(jié)果,計(jì)算得LaMn2Ge2在1.43×106A/m外場變化下居里溫度附近的最大磁熵變?yōu)?.42 J/kg·K.

Abstract:探索了用水平連鑄的方法制備BFe30-1-1銅合金空心管坯的技術(shù),在實(shí)驗(yàn)室成功制備了φ83mm×20mm空心管坯。對(duì)管坯的表面質(zhì)量,凝固組織及力學(xué)性能進(jìn)行了分析。結(jié)果表明,采用合適的熔鑄工藝參數(shù),可以用水平連鑄的方法制備BFe30-1-1銅合金空心管坯。

Abstract:采用熔體快淬及退火方法制備了Nd10.1Fe(82.2-x)Co5Zr2.7Bx(x=6.2,6.5,6.7,7)納米晶雙相永磁體.結(jié)果表明,優(yōu)化B的含量,可使晶粒細(xì)化、均勻,并對(duì)其磁性能有一定的影響,在x=6.7時(shí),快淬速度為16m·s-1,有顯著的剩磁增強(qiáng)作用,各向同性剩磁比Mr/Ms=0.758,并且Nd10.1Fe(82.2-x)C05Zr2.7Bx粘結(jié)磁體出現(xiàn)最佳性能,其剩磁和最大磁能積分別為Br=0.72 T,(BH)max=85.0 kJ·m-3.

Abstract:研究了以AM50鎂合金為基體，Si含量分別為0．5％，0．93％和1．91％（質(zhì)量分?jǐn)?shù)，下同）時(shí)的3種鎂合金在壓鑄狀態(tài)下的顯微組織、流動(dòng)性、力學(xué)性能和斷裂特征。在含硅合金中觀察到Mg2Si相的2種不同形貌，即多邊形顆粒狀與大塊漢字狀。Si元素能改善鎂合金的流動(dòng)性，提高合金硬度，但過高時(shí)（〉0．93％）會(huì)導(dǎo)致合金的室溫力學(xué)性能下降。拉伸試樣斷面表現(xiàn)為脆性的解理或準(zhǔn)解理斷裂。Si元素能降低鎂合金的沖擊韌性。

Abstract:針對(duì)TC4鈦合金鍛件誤加工造成的銑槽和面尺寸超差進(jìn)行了激光快速修復(fù)研究。修復(fù)區(qū)與鍛件基體之間形成致密冶金結(jié)合，修復(fù)區(qū)組織為柱狀原始聲晶界內(nèi)編織細(xì)密的α＋β網(wǎng)籃組織，晶內(nèi)α板條的寬度〈1μm。修復(fù)過程中發(fā)現(xiàn)粉末狀況、激光加工參數(shù)影響到修復(fù)區(qū)中氣孔、層間或道間熔合不良等缺陷的形成，通過采用粉末真空干燥處理、優(yōu)化工藝參數(shù)等方法獲得了修復(fù)區(qū)內(nèi)無氣孔、熔合不良等缺陷的修復(fù)試樣。修復(fù)試樣的室溫靜載拉伸性能測試結(jié)果表明，其抗拉強(qiáng)度達(dá)到1000MPa，屈服強(qiáng)度達(dá)到925MPa，延伸率為8．0％，接近鍛件本體性能。

Abstract:The microstructures and impact toughness of thermal simulated welding HAZ in 2205 duplex stainless steel were studied by means of thermal simulator and impact testing in the paper. The influences of cooling time on the impact toughness of thermal simulated HAZ were investigated also. The results show that the cooling time has strong effects on the impact toughness of the thermal simulated HAZ, that the ferrite content and micro hardness decreases as increasing of cooling time, that the microhardness in ferrite is lower than that than in austenite, that impact toughness increases with the increase of the cooling time t12/8 for a certain cooling time t8/5, and that impact toughness decreases with the increase of the cooling time t8/5 for a certain cooling time t12/8.

Abstract:利用雙層輝光等離子表面冶金技術(shù)對(duì)Ti2AlNbO相合金進(jìn)行滲Mo工藝研究。采用掃描電子顯微鏡、輝光放電光譜分析儀、X射線衍射儀和顯微硬度計(jì)測試了滲Mo層的微觀組織、化學(xué)成分、相組成和顯微硬度。采用可控氣氛微型摩擦磨損實(shí)驗(yàn)儀進(jìn)行耐磨性研究。在最佳工藝參數(shù)下，滲Mo層可達(dá)100μm，表面Mo含量超過90％，且從表面到心部呈梯度分布。滲Mo層主要由純Mo及Al5Mo相組成，硬度HV達(dá)8000MPa，滲Mo試樣的平均摩擦因數(shù)為0．085，較Ti2AlNb基材降低6倍，磨損率僅為基材的7．5％。結(jié)果表明：Ti2AlNbO相合金表面的耐磨性能得到極大地提高。

Abstract:研究了3種不同含Ti量單晶高溫合金的鑄態(tài)、熱處理態(tài)組織及持久性能。結(jié)果表明：Ti含量對(duì)合金的微觀組織和持久性能都有明顯的影響。隨著鈦含量的增加，鑄態(tài)合金枝晶間區(qū)域的共晶尺寸和含量明顯增大、增多，枝晶間區(qū)域的面積也逐漸增大。熱處理后，3種合金的枝晶干處的γ′相形態(tài)基本一致，都為規(guī)則的立方體γ′相，尺寸大約為400nm-500nm。隨著鈦含量的增加，合金的持久壽命略有降低，延伸率略有增加。

Abstract:通過XRD分析了Sm2Fe17合金的氮化行為及該過程中合金的結(jié)構(gòu)演變規(guī)律.結(jié)果表明Sm2Fe17合金粉末在460℃～510℃氮化5 h的過程中,隨著氮化溫度的升高,合金的晶格常數(shù)、體積膨脹量不斷增加,預(yù)示著合金中氮含量的增加,490℃時(shí)角度偏移量最大達(dá)到約0.9°,晶胞體積膨脹量達(dá)6.568%,合金中的氮含量達(dá)到最大值;500℃以后氮化物的分解占主導(dǎo)地位.同時(shí),建立了Sm2Fe17合金粉末的氮化過程的物理模型.

Abstract:采用熔融法制備Bi100-xSbx熱電材料,并在550K經(jīng)過500 h的恒溫加熱.用SEM分析了材料的微觀形貌,在80 K～300K溫度范圍內(nèi)測試了材料的電阻率、Seebeck系數(shù)、熱導(dǎo)率隨溫度的變化,討論了材料優(yōu)質(zhì)系數(shù)隨溫度的變化關(guān)系.x=13的樣品在80 K優(yōu)質(zhì)系數(shù)達(dá)到4.3×10-3K-1.

Abstract:The progress has been made in the area of extending photocatalytic performance of TiO2 by doping in different methods, which makes titanic the promising material for its application in decomposing contamination of atmosphere and water. The modification methods, including metal cation doping, metalloid anion doping, compound anion doping etc, are dealt with in this review.

Abstract:In this paper, progress in research of TiAl matrix composites at home and abroad was reviewed. The mechanical properties of some typical long fibers, short fibers, whiskers and particles reinforced TiAl matrix composites were summarized. Various technologies and features for preparing TiAl matrix composites were discussed especially.