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Abstract:本文從精巧的實(shí)驗(yàn)測(cè)量和獨(dú)到的理論計(jì)算兩方面對(duì)碳納米管楊氏彈性模量的研究方法、實(shí)驗(yàn)原理、基本理論、主要發(fā)現(xiàn)及意義等進(jìn)行討論。實(shí)驗(yàn)測(cè)量方法主要包括CNTs自由端振動(dòng)法、AFM探針偏折或拉伸CNTs等，理論計(jì)算方法主要涉及到連續(xù)體模型，分子動(dòng)力學(xué)模擬或兩者相結(jié)合的混合方法。

Abstract:Some basic problems in preparing YBCO superconductor by directional solidification, including the peritectic reaction , the interface stability and its control , the orientation of solidification, and crystal orientation control , were discussed. Many problems have been revealed and must be overcome in the future, in order to get an optimum structure.

Abstract:The purpose of this article is to review the development and applications of titanium and its alloys on dental material, including the elastic modulus, the tensile strength, the yield strength and the extensibility of dental Ti alloys, the effects of halogen ions on the corrosion of dental Ti alloy, the galvanic couple corrosion of Ti alloy combined with others type metal and the microbiological corrosion of dental Ti alloy in oral environment, the surface characteristic and the effect of roughness on the wettability, the recommended alloy elements and using d-electron alloy design theory when designing new dental Ti alloys. The existing problems and the research tendency of dental Ti and Ti alloy were discussed.

Abstract:This paper reviews the analytical measurements of thermal residual stresses (TRS) for continuos fiber reinforced titanium matrix composites, such as X-ray and neutron diffraction, layer removal method, slitting method, selectively matrix corrosive method and so on, and the effect of TRS on mechanical properties of the composite, and discusses the different kinds of methods for reducing the thermal residual stresses. Finally, present investigative limitation and areas for further research are outlined.

Abstract:The preparation of in-situ particulate reinforced titanium alloy matrix composites in recent years were reviewed, which includes powder metallurgy, melting-casting, XDTM (Exothermic Dispersion), SHS(Self-propagating High-temperature Synthesis), SHS-melting- casting, CR(Contact Reaction ), MA(Mechnical Alloying), laser-melting cladding et al. Microstructures of carbide and boride reinforced respectively titanium alloy matrix composites by different fabrication methods were reviewed. The carbide reinforcements include TiC, Ti2AlC, Ti3AlC et al. The boride reinforcements include TiB2 and TiB. The morphology of reinforced phase were analyzed respectively. Future prospect for these titanium alloy matrix composites was discussed.

Abstract:Employing differential scanning calorimetry (DSC) and transmission electron microscopy (TEM), the isothermal crystallization process and precipitated phases of Zr41.2Ti13.8Cu12.5Ni10Be22.5 (at%) bulk amorphous alloy were investigated. It is found that the bulk amorphous alloy exhibited a multi-stage crystallization behavior when being isothermal annealed. The precipitated phases are different at various crystallization stages. The experiment results show that the main precipitation phase is body-centered tetragonal (b.c.t) Zr2Cu at the first crystallization stage but primitive hexagonal ZrBe2 at the second stage, confirming that the Zr41.2Ti13.8Cu12.5Ni10Be22.5 bulk amorphous alloy possesses a phase separation tendency during the isothermal annealing processes. The X-ray diffraction (XRD) result validated that the main precipitation phases were Zr2Cu and ZrBe2 when the bulk amorphous alloy was fully crystallized.

Abstract:為了給研究合金在凝固過(guò)程中發(fā)生收縮、遷移現(xiàn)象和偏析提供科學(xué)依據(jù),我們用改良靜滴法對(duì)鎢濃度為0到15%的液態(tài)Ni-W二元合金的密度進(jìn)行了測(cè)量.結(jié)果表明Ni-W二元合金的液態(tài)密度隨溫度的增加而減少,但隨合金中鎢濃度的增加而增加;液態(tài)Ni-W二元合金的摩爾體積隨溫度和合金中鎢濃度的增加而增加.金屬鎢在Ni-W二元合金中的偏摩爾體積約為(10.80-1.35×10-3T)×10-6m3·mol-1.

Abstract:Ignition-proof magnesium alloy was acquired by the addition of rare earth elements(Y,Ce). The alloy at 1 173 K exposure to air for 0.5 h can not be ignited. XRD and SEM analysis revealed that the protective oxide film with two layers structure was formed on the surface of Mg-Y-Ce alloy. Thermogravimetric measurements indicated that the oxidation dynamics curve measured at 673 K and 773 K follows the parabolic-line law and the curve investigated at 873 K follows complicate quartic law.

Abstract:用元素混合法研究了粉末冶金Ti-NdAl合金的燒結(jié)致密化行為及力學(xué)性能。結(jié)果表明，粉末冶金Ti-NdAl合金中由于稀土元素釹的存在，其燒結(jié)過(guò)程中出現(xiàn)液相，同時(shí)稀土釹對(duì)鈦粉末表面氧有凈化作用，二者促進(jìn)了粉末鈦的致密化過(guò)程。燒結(jié)密度可以達(dá)到99％以上。顯微組織分析表明，粉末燒結(jié)Ti-NdAl合金是單相。相，隨著釹含量的增加，晶粒細(xì)化。該合金燒結(jié)態(tài)試樣中存在生長(zhǎng)孿晶。對(duì)粉末冶金Ti-NdAl合金的室溫力學(xué)性能檢測(cè)結(jié)果表明，隨著稀土釹含量的增加，Ti-NdAl合金室溫拉伸強(qiáng)度不變，而塑性得到大幅度改善。Ti-1．6％Nd0．4％Al合金的強(qiáng)度為728MPa，延伸率為15％。

Abstract:采用聲電化學(xué)工藝在CVI C／C復(fù)合材料表面制備了HA涂層，分別用SEM，XPS，EDAX和XRD表征了CVI C／C和HA的表面形貌、組成和結(jié)構(gòu)，同時(shí)對(duì)比了成骨細(xì)胞在其表面的粘附、增殖和堿性磷酸酶活性的表達(dá)。制備的HA涂層為球狀形貌，由納米片狀晶體構(gòu)成。細(xì)胞培養(yǎng)初期，粘附于HA涂層表面的細(xì)胞數(shù)與CVI C／C表面的細(xì)胞數(shù)無(wú)顯著差別，成骨細(xì)胞在CVI C／C表面易鋪展在孔的邊緣，8h后粘附于HA表面的成骨細(xì)胞數(shù)顯著多于CVI C／C表面。HA涂層提高了細(xì)胞的增殖能力，成骨細(xì)胞堿性磷酸酶在HA涂層表面的表達(dá)也優(yōu)于CVI C／C材料。結(jié)果表明，聲電化學(xué)制備的HA涂層提高了CVI C／C材料的生物活性和生物相容性，可以加速成骨細(xì)胞的粘附、增殖、分化和成熟。成骨細(xì)胞在材料表面的粘附機(jī)制是由多因素綜合作用的，材料的表面形貌和生物活性在細(xì)胞粘附過(guò)程的早期發(fā)揮著重要作用。

Abstract:A method of synthesizing novel anodic alumina films with antibacterial property is presented. The process includes preparing a film by anodic oxidation of aluminum and subsequently introducing silver to the films. The antibacterial effect of such a film was estimated by in vitro tests. Escherichia Coli and Staphylococcus aureus were chosen as bacteria to test the antibacterial capacity of such films. It is found that the antibacterial effect was achieved by releasing of silver ions and the effect could be lasting for more than 24 months in atmospheric condition. Scanning electron microscopy was employed to survey antibacterial film. The chemical state of silver in the films was analyzed by X-ray photoelectron spectrum, and Auger electron spectrum was performed to determine the concentration of silver atoms in various films. Ions releasing experimental was carried out in water and the mixture of water and dilute nitric acid, the amount of silver ions releasing from the film was measured, and the total amount of silver in the films was more than 0.13 mg. This antibacterial film can be widely applied and its antibacterial effect maintained for a long time.

Abstract:The La0.67Mg0.33Ni2.5Co0.5 hydrogen storage alloy with PuNi3-type was prepared using induction melting followed by heating treatment. In order to compensate Mg loss during alloy melting, the different mass percent Mg was supplemented into the melt. The microstructure and electrochemical properties of the alloys were investigated by using XRD and electrochemical method. The results show that the ingot is composed of main phase with PuNi3 type structure and a little second phase with CaCu5 structure. After heat treatment at 1 223 K for 10 h, the amount of the second phase in the annealed alloy is remarkably decreased and a more homogenous and purified PuNi3 type microstructure is obtained in the case of 10% Mg supplement. The electrochemical analyses show that the electrochemical properties of the alloy, such as activation, capacity, cycling stability and discharge ability at different current density, are well improved by supplementing proper Mg and annealing heat treatment. In comparison with AB5 type and AB2 with laves phase hydrogen storage alloys, the La0.67Mg0.33Ni2.5Co0.5 alloy has high capacity and quite good kinetics of electrochemical reaction.

Abstract:The process, inductor structure, and screen of electromagnetic shaping for plate-form with big width-to-thick ratio is studied. The results indicate that the logical structure of inductor can melt plate-form equably along its perimeter in cross section and confide melt to a certainty. Screen can regulate the magnetic flux density distribution to assure melt in ideal state in shaping inductor. There is a rational drawing velocity to match electrical power at the constant conditions. At last, the superalloy plate-form parts with qualified surface and directional solidification structure are obtained.

Abstract:On base of the principle of bulge/blister, special experimental equipment adapted for precise quantitative evaluation of the adhesive strength of diamond thin films was designed and fabricated, and free-standing windows sample of diamond thin film was fabricated by a new method developed on the base of conventional process technology of Si plane, which can ensure full diamond coatings from damage during the process of etching the free-standing windows. The average adhesion strength of diamond thin films calculated from the tests of the square membranes is 4.287 26 J/m2, which was coincident with simulation outcomes, so it was approved that the initial calculating model was validity. According to these test results, the adhesive strength could be obtained precisely and quantitatively by bulge/blister test, which can provide a basis for the optimization of diamond thin films fabrication technics and a criterion for the quality evaluation of diamond thin films, and the results will be beneficial to wide application of diamond thin films in the tool-engineering field.

Abstract:The test specimens which consist of Ni20 alloy powder as a cladding metal on the stainless steel 1Cr18Ni9Ti substrate was prepared by using laser rapid forming process and the residual stress distribution in the specimens was analyzed through the hole-drilling method. The results show that the residual stress level in the specimens is lower and belongs to low residual stress domain. The cladding metal near the substrate bore with a compressive stress parallel to the direction of laser scanning. With the increase of the number of cladding layer the value of the compressive stress minimizes gradually and transforms to tensile stress with the value increasing. Conversely, the residual stress perpendicular to the direction of laser scanning is smaller.

Abstract:采用電化學(xué)測(cè)試技術(shù)、X射線(xiàn)衍射等技術(shù)研究了Ti0．8Zr0．2V1．6Mn0．8Ni0．6(0≤x≤0．64)貯氫電極合金的結(jié)構(gòu)和電化學(xué)放電特性。研究表明：合金由C14 Laves相和BCC相構(gòu)成；鉻替代錳的量越多，枝晶組織越粗大。X射線(xiàn)衍射發(fā)現(xiàn)替代影響合金的晶格參數(shù)。合金的最大電化學(xué)放電容量為545mAh／g，電化學(xué)活化容易，但循環(huán)性能比較差。隨著替代量增大，由于鉻抑制了鈦、鋯和釩元素的表面遷移和氧化使合金的循環(huán)性能退化明顯減輕，但同時(shí)因?yàn)樘娲咕О^(guò)大導(dǎo)致最大電化學(xué)放電容量有所降低。

Abstract:The nanocrystalline powder of Al-15%Pb-4%Si-1%Sn-1.5%Cu (mass%) were prepared by mechanical alloying. Systematical investigations were carried out on the structural change, grain size, lattice constant, morphology of the powder and the chemical composition of the Al-15%Pb-4%Si-1%Sn-1.5%Cu high energy ball milled powder using X-ray diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscopy(SEM). The experimental results showed that the nanocrystalline powders were synthesized and the homogenous nanophases was achieved by mechanical alloying. The effect of ball milling was more evident to lead than to aluminum. The grain size of Pb was 40 nm after milling for 40 h, and the grain size of aluminum was 65 nm after milling for 60 h. The solid solutions of Al(Cu, Si) and Pb(Sn), and supersaturated solid solution of Pb(Al) were observed by MA. Otherwise, brittle element powder of silicon was more difficulty alloying in the mechanical alloying process.

Abstract:采用水淬法制備了Zr—Ti—Cu—Ni—Be—Co塊狀非晶合金(BMGs)。使用XRD進(jìn)行相分析，采用熱分析儀進(jìn)行玻璃轉(zhuǎn)變溫度、晶化溫度和熱穩(wěn)定性等的測(cè)定，用SEM觀察試樣壓縮后的外表面和斷口形貌。研究了Co對(duì)Zr—Ti—Cu—Ni—Be合金非晶形成能力(GFA)、熱穩(wěn)定性及力學(xué)性能的影響。結(jié)果表明：含Co的所有Zr—Ti—Cu—Ni—Be BMGs都有1個(gè)明顯的玻璃轉(zhuǎn)變點(diǎn)和寬的過(guò)冷液相區(qū)(△T）。Zr38Ti17Cu10.5Co12Be22.5合金具有和Zr41Ti14Cu12.5Ni10Be22.5合金相當(dāng)?shù)摹鱐；Co的添加明顯提高Zr—Ti—Cu—Ni—Be BMGs的力學(xué)性能，含Co量大于10at％的Zr—Ti—Cu—Ni—Be BMGs的壓縮斷裂強(qiáng)度（σf）超過(guò)2000MPa，Zr38Ti17Co22.5Be22.5合金的σf達(dá)到2230MPa，比Zr41Ti14Cu12.5Ni10Be22.5合金的σf提高23％。

Abstract:The effects of rapid quenching on the cycle stability of the H2-storage electrode alloy with AB2 Laves phase were investigated comprehensively. The phase structures and morphologies of as-cast and quenched alloys were determined and observed by XRD and SEM. The results showed that the influences of rapid quenching on the cycle stability of the H2-storage electrode alloy with AB2 Laves phase was closely related to the compositions of the alloys. The cycle life of Ti-based electrode alloy could be enhanced in certain degree by rapid quenching. For Ti-Zr-based electrode alloy, its cycle life could be exalted dramatically with the increase of quenching rate. The main reason of different influence of rapidly quenching on the cycle stability of the electrode alloy was attributed to that the quantities of the amorphous formed by rapid quenching in alloys were different.

Abstract:采用 ECAP 方法和 3 種工藝路徑,研究純鋁的顯微組織和力學(xué)性能的變化。研究發(fā)現(xiàn),對(duì)于φ-120°模具來(lái)說(shuō),在 3 種工藝路徑中,路徑 A 的晶粒細(xì)化效果最明顯,其次為路徑 Bc,路徑 C;6 次 ECAP 后,采用路徑 Bc 試樣的顯微組織由等軸晶組成,而采用路徑 A 和路徑 C 時(shí)試樣的顯微組織由拉長(zhǎng)的纖維狀晶粒組成,平均晶粒尺寸均能小于 1 μm。相應(yīng)地,3種工藝路徑提高強(qiáng)度的有效性依次為路徑A,路徑Bc,路徑C,變形過(guò)程中σ0.2同晶粒尺寸的關(guān)系符合Hall-petch關(guān)系。ECAP 過(guò)程中純鋁的強(qiáng)化機(jī)制主要是細(xì)晶強(qiáng)化,并初步探討了 ECAP 過(guò)程中細(xì)晶的形成機(jī)制。

Abstract:研究了鋁含量對(duì)定向凝固N(yùn)i3Al基合金鑄態(tài)和熱處理態(tài)顯微組織的影響，用定向凝固技術(shù)制取合金。測(cè)試了合金的高溫持久性能，利用SEM，EDS，XRD等考察了持久斷裂試樣的微觀形貌。結(jié)果表明，鋁含量在6．5％～9．5％(質(zhì)量分?jǐn)?shù)，下同)范圍內(nèi)，合金的鑄態(tài)組織由γ′，γ和MC碳化物組成，9．5％Al的合金形成大量的γ′初晶和少量β—NiAl相；1300℃，4h固溶熱處理使次生γ′全部固溶，共晶γ′固溶很少，直到合金初熔γ′初晶和β—NiAl相仍不能固溶，嚴(yán)重?fù)p傷合金的高溫強(qiáng)度；在1100℃，70MPa條件下持久時(shí)間高于10h時(shí)，合金即出現(xiàn)明顯的筏排組織，持久裂紋主要沿柱晶橫向段和枝晶間萌生擴(kuò)展。7．5％～8．5％的鋁含量是添加了W，Mo，Ta，Ti等合金元素的定向凝固N(yùn)i3Al基合金的適宜范圍。

Abstract:采用機(jī)械合金化合成了新型合金LaNi5—38％Mg(質(zhì)量分?jǐn)?shù)，下同)，并采用X射線(xiàn)衍射(XRD)，掃描電子顯微鏡(SEM)，差熱分析(DTA)等對(duì)其結(jié)構(gòu)、形貌及熱穩(wěn)定性能等進(jìn)行了表征。結(jié)果表明：經(jīng)280r／min球磨250h后，LaNi5—38％Mg合金由非晶和MgNi2納米晶(5．4nm)組成：所得粉末大多數(shù)為規(guī)則的近球形或球形，另有少量的多角形或梨形，其粒徑為0．05μm～13．9μm，其中90％的顆粒為0．5μm～2．0μm。球磨試樣經(jīng)763K保溫35d，獲得了熱穩(wěn)定性較好的具有納米尺度(25.3nm)的三相合金。

Abstract:The effect of Mn and Zr on the microstructures and properties of new type Al-Mg-Si-Cu alloys were studied, the type and composition of the precipitates were analyzed by XRD, EDAX and TEM. The results showed that the strength decreased and ductility increased with adding Zr. Adding both 0.03%Mn and 0.08%Zr, granular or rod AlCrMnFeSi dispersoids were present profusely in the microstructures of the alloy-T6, both the strength and ductility of the alloy increased. Continuously increasing Mn and Zr, the properties decreased due to the reduce of precipitate-strengthening phase Mg2Si and the occurrence of coarse AlCrMnFeSi.

Abstract:Copper-polyimide specimens were presented by chemical vapor deposition (CVD) and physical vapor deposition (PVD) methods, and TiN thin films were deposited by PVD as a diffusion barrier. TiN barriers have shown to be very effective against copper diffusion. The effect of annealing treatment on the adhesion characteristics of copper films were studied. CVD copper films showed small residual stress and high adhesion strength, but for PVD copper film, much residual stress left in copper film when TiN barrier was used. The adhesion improvement by annealing treatment was attributed to the removal of tensile residual stress in copper films in Cu/TiN/PI.

Abstract:研究了MB3鎂合金的攪拌摩擦焊技術(shù)。對(duì)其塑性連接時(shí)的焊縫成形，焊縫組織形態(tài)及接頭的力學(xué)性能進(jìn)行了分析。結(jié)果表明，用攪拌摩擦焊方法焊接MB3鎂合金，當(dāng)工藝參數(shù)合適時(shí)，可獲得外觀成形美觀、內(nèi)部無(wú)缺陷，幾乎無(wú)變形的平板對(duì)接接頭。接頭力學(xué)性能試驗(yàn)表明，其抗拉強(qiáng)度可達(dá)母材的97．2％，高于熔焊接頭的強(qiáng)度，斷裂位置大多位于熱影響區(qū)。

Abstract:采用Sol—Gel工藝在普通玻璃表面制備出均勻、透明的添加0．3％～0．5％貴金屬Pd^2 的TiO2-SiO2復(fù)合薄膜。通過(guò)對(duì)薄膜的XRD，SEM表征及薄膜耐酸、堿化學(xué)穩(wěn)定性的檢測(cè)，結(jié)果表明，在TiO2—SiO2薄膜中添加Pd^2 ，增強(qiáng)了TiO2薄膜的光催化活性，由于Pd^2 所起到阻滯劑的作用，使晶粒尺寸減小，表面呈多孔合理結(jié)構(gòu)，改善了TiO2薄膜的顯微結(jié)構(gòu)，使薄膜的化學(xué)穩(wěn)定性得到明顯的提高。

Abstract:采用雙層輝光無(wú)氫離子滲碳技術(shù)在本底真空為 5×10-3Pa 的情況下,用 99.999%的高純氬氣對(duì) Ti-6Al-4V 鈦合金進(jìn)行無(wú)氫滲碳。檢測(cè)結(jié)構(gòu)為:滲碳層厚度大于 200μm;表面層有一層以 TiC 為主的沉積層;在滲層中有 TiC 相生成;滲層的近表面硬度為 7 000 MPa;與剛玉球的摩擦力矩大幅度降低。通過(guò)研究得出:鈦材經(jīng)過(guò)雙輝離子無(wú)氫滲碳后,不僅提高了表面的硬度,同時(shí)降低了摩擦系數(shù),因而使耐磨性能得到了提高。

Abstract:采用溶膠-凝膠技術(shù)制備了摻雜納米CeO2的納米玻璃，探索了不同溶劑、pH值、熱處理溫度和升溫速率等制備條件對(duì)納米玻璃的影響，獲得了最佳的制備條件，得到了透明的摻雜納米CeO2的納米玻璃。其中反應(yīng)物最佳摩爾比為：nTEOS：ni-PrOH：nEOH：nH2O=1：2：1：20；最佳pH值為：1．4～118；凝膠化的理想環(huán)境為：T65℃～70℃，潤(rùn)濕氣氛；制備干凝膠的最佳熱處理路線(xiàn)為：水浴70℃，3d→水浴85℃，3d→烘箱100℃，1d→烘箱150℃，2d。因此，溶膠-凝膠技術(shù)是制備納米玻璃的有效途徑。

Abstract:用 SEM 的波譜(WD)分析手段,定性研究了合金元素鈮在 Zr-Sn-Nb-Fe 合金中的存在方式及其與中間退火工藝的關(guān)系。研究結(jié)果表明添加的合金元素鈮主要存在于 Laves 相中,并且隨中間退火溫度升高,第二相中鈮含量增加。鈮在 α-Zr 中的含量隨退火溫度升高而降低,可降低至小于 1×10-4,這與二元 Zr-Nb 合金中合金元素鈮的固溶度隨溫度升高而增加明顯不同。鈮和鐵、鉻共存于鋯合金中時(shí),將與鐵、鉻一起優(yōu)先形成沉淀相,導(dǎo)致合金元素主要存在于第二相中,并出現(xiàn)其在 α-Zr 中固溶量隨退火溫度升高而降低的現(xiàn)象;其原因可歸結(jié)為隨退火溫度升高鈮擴(kuò)散能力增加,從而導(dǎo)致在第二相中含量增加。