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Abstract:Two powder metallurgic methods of manufacturing TiAl based alloy sheet, including elemental powder metallurgy and pre-alloying powder metallurgy, are briefly reviewed. And the fabricating processes and materials properties of elemental powder metallurgy, elemental foil powder metallurgy, hot rolling of pre-alloyed powders, physical vapor deposition and plasma spraying are introduced. Meanwhile, the process characteristics and prospects for these techniques are also described.

Abstract:介紹了Ti-V-Ni，Ti-V-Mn和Ti-V-Cr3種固溶體合金作為儲氫合金或電極材料的研究現(xiàn)狀。對無電化學(xué)活性的基質(zhì)合金，用元素取代、合成復(fù)合合金和多相合金等多種方法，得到一些性能較好的負(fù)極材料。同時(shí)指出了固溶體合金的特點(diǎn)和研究工作的方向。

Abstract:The concept and the development background of titanium matrix functionally gradient materials(FGM)complex structure are introduced.The macro-meso-scopic scale of research results of FGM are reviewed and the development trends in the area are prospected.By gradually varying the volume fraction of the constituent materials, their material properties exhibit a smooth and continuous change with respect to the spatial location, thus being void of interface problems that are usually associated with fiber-reinforced composites and with less severe thermal stress concentrations. FGMs are now developed for general use as structural components in extremely high temperature environments. The current status of research and the application prospects for materials optimization analysis of FGM complex structure are especially discussed.Future research needs are highlighted.

Abstract:The precipitates size distribution and morphology in an Al-Zn-Mg-Cu-Li alloy are studied by small angle X-ray scattering and transmission electron microscopy. The results show that the precipitates belong to ellipsoid and their axis ratio range is between 0.2 and 0.4, aged under different conditions. The logarithm Gaussian distribution of effective size and the Maxwell distribution of particles mass with gyration radius are also constructed. The changing of both types of distribution curves with kinetic strength Ks has been analyzed.. The results show that the geometric average and distribution width for both types of distribution curves increase with kinetic strength.

Abstract:通過研究GPS燒結(jié)氮化硅陶瓷的室溫和高溫抗彎強(qiáng)度、晶界相含量和成分以及晶界析晶相隨氮化硅粉料表面氧含量的變化規(guī)律，發(fā)現(xiàn)當(dāng)粉料表面氧含量低于1．35mg／m^2時(shí)，氮化硅陶瓷在室溫下的抗彎強(qiáng)度基本保持不變。試樣在1200℃時(shí)的抗彎強(qiáng)度明顯低于室溫強(qiáng)度，且隨著粉料表面氧含量的增加有一最高值。由于燒結(jié)助劑引入的O和Si在燒結(jié)過程中的還原氣氛下發(fā)生反應(yīng)而損失，燒結(jié)體中晶界相的實(shí)際含量顯著低于粉料中燒結(jié)助劑的加入量。隨粉料表面氧含量的增加，氮化硅陶瓷燒結(jié)體中的二次析晶相α-Y2Si2O7和β-Y2Si2O7消失，只有β-Si3N4晶相和晶界玻璃相存在。

Abstract:用金相顯微鏡、定量金相、掃描電鏡(SEM)、能譜分析(EDX)及X射線衍射(XRD)研究了0％，4％，6％Ta(質(zhì)量分?jǐn)?shù))3種成分的低Cr高W鑄造鎳基高溫合金鑄態(tài)及熱暴露后的顯微組織，結(jié)果表明：Ta是強(qiáng)MC碳化物形成元素，它形成MC碳化物的傾向低于Nb、高于Ti，當(dāng)合金中Ta的原子百分含量超過Nb3倍時(shí)，Ta在MC碳化物中的原子百分含量超過Nb。Ta是強(qiáng)γ'形成元素，它促進(jìn)共晶γ’的形成，在合金成分中以等量原子百分含量的Ta代替Al不會改變合金的共晶γ'數(shù)量。在高W鑄造高溫合金中M6C是比MC更加穩(wěn)定的碳化物，Ta的加入不能抑制1100℃，500h長時(shí)熱暴露后MC完全轉(zhuǎn)變?yōu)榱罨蚱瑺頜6C。MC分解時(shí)釋放的碳還促使σ(W,Mo) C→M6C反應(yīng)。對Ni-1．5Cr-10Co-16W-2Mo-5Al-1Ti-1Nb基礎(chǔ)成分合金，其最佳的含Ta量為4％(質(zhì)量分?jǐn)?shù))，而且含碳量應(yīng)低于0．07％(質(zhì)量分?jǐn)?shù))。

Abstract:在已有的泡沫金屬雙向名義載荷強(qiáng)度與孔隙率關(guān)系的基礎(chǔ)上，分析了該材料的雙向等應(yīng)力拉伸加載情形，探討了泡沫金屬在該情形下發(fā)生破壞的力學(xué)行為。研究結(jié)果顯示，以“八面體模型”推導(dǎo)出來的有關(guān)力學(xué)關(guān)系，較好地表征了該材料在雙向等載條件下的行為特點(diǎn)。

Abstract:In order to modify its cycle stability, a trace amount of boron was added in low-Co AB5-type hydrogen storage alloy. The low-Co AB5-type MmNi3.8Co0.4Mn0.6Al0.2B(x=0, 0.1, 0.2, 0.3, 0.4)hydrogen storage alloys were prepared by cast and rapid quenching. The x microstructures and electrochemical performances of the as-cast and quenched alloys were analyzed and measured. The effect of boron additive on the microstructures and cycle lives of the alloys were investigated comprehensively. The experimental results show that the addition of boron dramatically enhances the cycle lives of the as-cast and quenched low-Co AB5-type hydrogen storage alloys, whereas the action mechanism of boron is completely different.

Abstract:對定向凝固DZ4合金760℃和800℃下的低周疲勞行為進(jìn)行了研究，并結(jié)合斷口觀察，對其疲勞裂紋的萌生與擴(kuò)展進(jìn)行了分析。結(jié)果表明，DZ4合金760℃和800℃下的低周疲勞屬應(yīng)力疲勞，其損傷以彈性損傷為主，彈性損傷與疲勞壽命具有很好的相關(guān)性。定向凝固DZ4合金高壽命低周疲勞裂紋易于萌生于試樣內(nèi)部或亞表面的柱狀晶界。其疲勞裂紋的穩(wěn)定擴(kuò)展也較難形成典型的疲勞條帶。

Abstract:The molybdenum sheets doped with different contents of La2O3 (Mo-La2O3) were prepared by powder metallurgy and processing technology. Then their mechanical properties were tested by use of tension at room temperature with different velocity and their microstructures were discussed by means of SEM, TEM and XRD. It is shown that both the strength and ductility of molybdenum sheets are greatly improved by addition of La2O3. The maximum elongation of annealed Mo- La2O3 sheets is up to 46%. The experimental results can be reasonably explained by the interaction of La2O3 particles and dislocation as well as the toughening of second phase La2O3 .

Abstract:用金相顯微鏡，掃描電鏡，X射線衍射及密度測定，研究了90W-7Ni-3Fe和80W-10Ta-7Ni-3Fe2種成分合金。結(jié)果表明，含Ta合金在1400℃燒結(jié)時(shí)密度可達(dá)96.3％，合金密度隨燒結(jié)溫度提高而增加，在1460℃時(shí)密度達(dá)到最大；Ta原子固溶到硬質(zhì)相W和粘結(jié)相中，使得合金硬度明顯提高；含Ta合金斷口形貌中，粘結(jié)相呈沿晶斷裂、W晶粒穿晶斷裂及其脫出具有相當(dāng)比例；Ta粉末粒度對合金力學(xué)性能、微觀組織及斷裂方式均產(chǎn)生顯著影響。

Abstract:利用電阻爐加熱，采用電子顯微鏡及圖象分析儀，研究了近液相線鑄造A356鋁合金在二次加熱過程中的組織變化。結(jié)果表明：近液相線鑄造鋁合金A356在580℃～590℃加熱，保溫10min，晶粒仍保持細(xì)小、近似等軸的組織特點(diǎn)。隨著加熱溫度的升高和保溫時(shí)間的延長，初生相尺寸增加較小，具有較高的熱穩(wěn)定性。

Abstract:Directional solidification of peritectic alloy described is significant for advanced materials processing. The nucleation and growth mechanisms of peritectic phase are outlined and the nucleation undercooling of peritectic phase is small as a result of the presence of properitectic phase nuclei. On the basis of assuming maximal interface growth temperature or nucleation and constitutional undercooling criterion (NCU), the microstructure and phase selection of peritectic alloy have been considered. It was found that the peritectic reaction as one of the growth mechanisms of peritectic phase existed not only at the S/L interface, but also in the directionally solidified sample of Sn-Cu peritectic alloy. Finally, the problems for directional solidification of peritectic alloys were presented to deeply and rigorously explore the solidification theory and experiment of peritectic alloy.

Abstract:測定了LaNi5-xAlx(x=0，0．1，0．2，0．3)系合金在吸放氫過程中的貯氫性能。結(jié)果表明，貯氫容量隨合金中Al含量的增加而降低，平臺壓力和熱力學(xué)焓變和熵變隨合金中Al含量的增加而降低，合金形成氫化物的穩(wěn)定性增強(qiáng)；LaNi5-xAlx系合金在吸放氫過程中的平臺壓力存在一定的差異，即滯后現(xiàn)象，滯后系數(shù)隨合金中Al含量的增加而降低，這是LaNi5-xAlx系的晶胞體積隨合金中Al含量的增加而增加的必然結(jié)果;LaNi5-xAlx系合金的吸放氫動力學(xué)參數(shù)也與合金中的Al含量有關(guān)，活化能隨Al含量的增加而降低，但活化能不存在數(shù)量級的差異。

Abstract:采用凝膠注模技術(shù)原位合成造孔劑制備出開孔氣孔率為20％～30％的La0．8Sr0．2MnO3多孔陰極材料。結(jié)果表明，合適的燒結(jié)溫度為l100℃～1150℃；開口氣孔位于三角晶界，中位孔徑約為400nm；多孔材料的電導(dǎo)率隨著溫度的升高而升高，由ln(σT)-1／T曲線，可得電導(dǎo)活化能Ea為10．99kJ／mol。

Abstract:Nano-Al2O3 dispersion strengthened Ni-based alloy coatings produced by crosscurrent CO2 laser on Ni-based superalloy are introduced. Cross-section of the coatings have been examined to reveal their microstructure, using optical microscope and SEM (including EDS microanalysis). The results show that rapid directional solidification of epitaxy is found at the interface where the growth direction is perpendicular to the bottom of melting pool. The size of columnar dendrite is decreased by adding Al2O3 nanocrystalline to the powder. A novel microstructure of equiaxed solidification has been observed with the increasing a mount of Al2O3 to 1% (in weight). Fine and equiaxed microstructure has been obtained for the nanocrystalline Al2O3 acting as new nucleation site of the melting pool.

Abstract:研究了向原料粉中摻加Al粉對合成高純致密Ti3SiC2材料的影響。實(shí)驗(yàn)表明以2TiC／1Ti／1Si／0．2Al為起始原料組成，采用熱壓工藝在1200℃～1400℃的溫度范圍內(nèi)，可以制備得到密度達(dá)到理論密度98％以上的高純致密Ti3SiC2塊體材料。由XRD數(shù)據(jù)計(jì)算得到的晶格參數(shù)與文獻(xiàn)中的值接近。通過SEM和EPMA分析得知Ti3SiC2晶粒呈板狀結(jié)晶形貌，且發(fā)育良好，晶粒在平面內(nèi)的尺寸分別為3μm～8μm和4μm～10μm。

Abstract:Blue luminescence at about 431nm is obtained from epitaxial silicon after sequential processing of C+ implantation, annealing in hydrogen ambience and chemical etching. With the increase of chemical etching, the blue peak was enhanced at first, decreased then and substituted by a red peak at last. C=O compounds induced during C+ implantation are embedded in the surface of nanometer Si formed during annealing, and nanometer silicon with embedded structure is formed at last, which contributes to the blue emission.

Abstract:采用磁控濺射方法在Si(111)基片上沉積Cu-Zr／ZrN薄膜體系作為擴(kuò)散阻擋層。通過比較Cu-Zr／ZrN薄膜體系和三元非晶(Mo，Ta，W)-Si-N的電阻率，同時(shí)比較Cu-Zr／ZrN薄膜體系和Ta，TaN的硬度，說明作為擴(kuò)散阻擋層的材料的選取，應(yīng)從整體性能上考慮，而不能僅僅考慮熱穩(wěn)定性等單一指標(biāo)。

Abstract:采用示差掃描量熱法(DSC)，X射線衍射(XRD)和振動樣品磁強(qiáng)計(jì)(VSM)研究了Nd60Fe20Al10-xCo10Bx(x=0，2，5)大塊非晶合金的結(jié)構(gòu)、磁性能和晶化行為。結(jié)果表明：Nd60Fe20Al10-xCo10Bx非晶合金在晶化前既沒有發(fā)生玻璃轉(zhuǎn)變也沒有過冷液相區(qū)；Nd60Fe20Al10Co10合金的DSC曲線上在360℃～475℃之間有1個(gè)寬的放熱峰，加入2at％～5at％的B后該放熱峰消失。鑄態(tài)Nd60Fe20Al10-xCo10Bx(x=0，2，5)大塊非晶合金在室溫具有硬磁性。隨B含量的增加，合金的內(nèi)稟矯頑力顯著增加，而飽和磁化強(qiáng)度和剩磁則有所下降。B的加入使Nd60Fe20Al10Co10合金的晶化行為發(fā)生明顯變化。

Abstract:Ferromagnetic Ni-Mn-Fe-Ga single crystal of a pseudoquaternary Heusler alloy has been invested as a new magnetic field control actuator material. A single crystal of Ni52Mn16.4Fe8Ga23.6 was grown in [001] direction of the cubic parent phase by the Czochralski method. The field-controlled shape memory effect and the temperature dependent of the magnetic-field-induced strain (MFIS) in Ni52Mn16.4Fe8Ga23.6 single crystal were investigated by measuring the field enhanced transformation strain and the MFIS with a magnetic field applied in different directions. The results show that such material combined with the martensitic transformation can produce the large field-enhanced transformation strain and the large MFIS. It is found that the MFIS is almost temperature independent, the maximum decreasing magnitude of the saturated MFIS is less than 10% from 265 K to 100 K. In addition, the direction in which the MFIS has the largest value is always the [001], namely the growth direction of the crystals. The results are discussed with reference to the shape memory characteristics of the alloys and the mechanism of the preferentially orientation of martensitic variants.

Abstract:采用粉冶法制備了添加Y2O3／CeO2(≤0．6w％)的復(fù)合強(qiáng)化鉬合金(MYC)絲。用XRD標(biāo)定合金相組成，用SEM觀察合金的顯微組織，用萬能電子拉伸機(jī)測定合金絲的力學(xué)性能并將測定結(jié)果與純鉬絲進(jìn)行了對比研究。研究結(jié)果表明：添加Y2O3／CeO2復(fù)合強(qiáng)化鉬合金的相組成為Mo，YMoO4和CeO2；MYC合金斷口具有典型的塑性斷裂特征，MYC合金絲在1600℃退火后仍然表現(xiàn)明顯的纖維狀織構(gòu)組織形態(tài)。

Abstract:The high temperature reaction between H2 and Ga2O3 is employed to obtain constant surface source of Ga, then high uniformity doping of Ga in Si is realized through SiO2-Si compound structure. By characterizing means of SIMS, SRP and four-point probe meter, the thermal distribution of P-type dopant Ga in SiO2 films, at the internal surface of SiO2-Si and near Si surface is analyzed respectively. The essence of open-tube Ga diffusion is revealed, which is closely related with both the rapid transportation of Ga through SiO2 film and the segregation effect of it at the internal surface of SiO2-Si. The mechanism of Ga concentration distribution is discussed accordingly.

Abstract:采用涂覆法制備了作為光催化劑的TiO2薄膜。XRD和SEM分析表明：所制備的TiO2為銳鈦型；薄膜表面呈現(xiàn)均勻的結(jié)構(gòu)；微晶平均粒度為22．7nm。在體外對胃癌細(xì)胞進(jìn)行了紫外光照TiO2光催化的實(shí)驗(yàn)，并同僅用紫外光和僅用TiO2的空白實(shí)驗(yàn)作了對照。用盒子維模型計(jì)算了所制備的催化劑表面分形維數(shù)。結(jié)果表明：所制備的納米TiO2催化劑表面分形維數(shù)介于2．52～2．57。分形維數(shù)較大的TiO2薄膜，對胃癌細(xì)胞的殺傷效果較好，殺傷率達(dá)80％。

Abstract:Phase structure and electrochemical properties of the storage hydrogen electrode alloys Zr1-xTix(Mn0.7V0.2 Co0.1Ni1.2)were investigated by XRD,SEM and EPMA, and electrochemical properties of the alloys were examined. The matrix alloys consisted of cubic C15 Laves phase and second phase (Zr7M10). With the increasing of Ti content, the lattice parameter of alloys decreased and C14 Laves phase appeared and increased. A little of TiNi phase appeared at x=0.1~0.2; however, Zr7M10 phase and TiNi phase decomposed at x=0.4~0.5, which demonstrated that high Ti content inhibited the appearance of second phase in the alloys. As a result, the storage hydrogen electrode alloy Zr0.8Ti0.2(Mn0.7V0.2Co0.1Ni1.2), the maximum discharge capacity of which is 354 mAh/g, possesses good rate capability. This contributes to change phase structure and phase composition, which plays a synergetic role in the charge-discharge process.

Abstract:TiO2 nanotube was synthesized successfully by hydrothermal process, using TiO2 powder and NaOH as the precurser. The micro-morphology and optical properties were characterized by XRD, SEM, HRTEM, UV Absorption Spectra Analyzer and Spectroradiometer, and the formation mechanism was also studied. The results showed that the product is anatase TiO2 nanotube with multiple layers wall, 10 nm~50 nm in the out-diameter, several micron to tens in the length, and opened in both of ends. The formation mechanism of the tube is coordinate with 3-2-1D model. The UV Absorption Spectra and PL spectra showed that the TiO2 nanotubes present blue-shift phenomenon compared to the raw material. The PL spectra also showed that at the visible band the luminous intensity of the TiO2 nanotubes increased obviously.

Abstract:用溶膠．凝膠(Sol-Gel)法制備了RE(RE=La，Y)-Mo復(fù)合氧化物粉末，工藝條件：初始溶液pH值=1，于550℃分解膠體，500℃，900℃ 2次還原粉末。采用XRD，TEM對還原后粉末的相組成、形貌、粒度進(jìn)行分析。結(jié)果表明：500℃還原后，單質(zhì)Mo衍射峰出現(xiàn)，RE以非晶態(tài)RE-O-Mo存在；900℃2次還原后，RE以氧化物形式存在。紅外光譜(FT-IR)分析結(jié)果表明，La和Y通過O與Mo鍵合，削弱Mo=O鍵，使稀土鉬復(fù)合氧化物可還原性增強(qiáng)。TEM分析表明，還原后稀土鉬粉末粒徑在70nm左右。

Abstract:自行設(shè)計(jì)了電弧腐蝕速率的測量方法，避免了一般電弧腐蝕速率測量中存在的不足，并對真空斷路器中常用的CuCr25，CuCr50觸頭材料以及純Cu和純Cr的電弧腐蝕速率進(jìn)行了測量。研究結(jié)果表明，純Cu，CuCr25，CuCr50和純Cr的電弧腐蝕速率分別為52．9μg／C，33．2μg／C，31μg／C和25．9μg／C。CuCr25和CuCr50的電弧腐蝕速率相差不大，都較純Cu有大幅度的降低，而與純cr的電弧腐蝕速率比較接近。此外，用SEM對4種觸頭材料經(jīng)100次燃弧之后的電極表面進(jìn)行了現(xiàn)測，清楚地反映了經(jīng)電弧腐蝕之后觸角材料的表面特征。

Abstract:采用DSC、彎曲實(shí)驗(yàn)和掃描電鏡分析研究了熱處理工藝對醫(yī)用TiNi合金細(xì)絲顯微組織、相變溫度和形狀記憶效應(yīng)的影響。結(jié)果表明，400℃～500℃，30min～120min熱處理時(shí)，隨著溫度的升高和時(shí)間的增長，TiNi合金細(xì)絲中Ti3Ni4析出相增多，相變溫度也升高。細(xì)絲經(jīng)500℃，30min處理后的最大可回復(fù)應(yīng)變量值最大。隨彎曲變形量的增加，疲勞壽命縮短。500℃處理的試樣疲勞壽命最長。

Abstract:Nanocomposite Nd9Fe85-xB6Inx magnets were synthesized by melt-spinning method. The effect between indium-dope and treating process on their magnetic properties were investigated by using XRD and VSM. The results show that both the coercivity and remanence ratio can be enhanced by a small indium-dope in Nd9Fe85B6 nanocomposite, while squareness of its hysteresis loop is also improved greatly. The optimum energy product increases remarkably from 95 kJ/m3 to 145 kJ/m3, while coercivity rises from 405 kA/m to 465 kA/m at 0~0.5 mol% indium-dope.

Abstract:以單質(zhì)Zn，Se和H2為原料，采用低壓化學(xué)氣相沉積方法在溫度為630℃～750℃，壓力為300Pa～1000Pa條件下制備出了性能優(yōu)異的ZnSe多晶材料。性能測試表明，制備出的CVDZnSe多晶材料在0．55μm～22μm，及8μm～14μm波段的平均透過率超過70％(1mm厚)，在3．39μm處的應(yīng)力雙折射為54nm／cm。其光學(xué)透過性能與美國采用Zn和H2Se氣體為原料制備出的CVD ZnSe多晶非常接近。

Abstract:采用電弧等離子體法成功制備了單晶態(tài)的納米鉭超微粒子，采用透射電子顯微鏡(TEM)、高分辨電子顯微鏡(HRTEM)對樣品進(jìn)行形貌、微觀結(jié)構(gòu)的觀察和分析，發(fā)現(xiàn)它具有規(guī)則的表面，平均粒徑大小在10am左右。并通過X射線衍射(XRD)分析其組成成分，發(fā)現(xiàn)在所制備的樣品中除鉭外還含有氧化鉭(δ-TaO)，估計(jì)是由于納米鉭粒子被氧化所形成的產(chǎn)物。

Abstract:Gallium nitride (GaN) films have been successfully fabricated on silicon (111) substrates through ammoniating Ga2O3/Al2O3 films deposited by rf magnetron sputtering. The formed films were characterized by Fourier transform infrared (FTIR) transmission spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) , scanning electron microscopy (SEM) and photoluminescence spectrum(PL). The results indicate that the films formed are polycrystalline GaN with hexagonal wurtzite structure.

Abstract:Mgx/Mg2Ni(x=10%, 30%, 50%) composites were synthesized by ball milling the mixture of Mg2Ni alloys and Mg powder. XRD analysis show that no new phase was produced, and the decomposability of Mg2Ni phase existed in the milling of solo Mg2Ni alloys is restrained in the milling of Mg2Ni alloys and Mg powder. Electrochemical characteristics of Mgx/Mg2Ni composites at different milling time were evaluated by simulated battery test. It was found that the discharge capacity of Mgx/Mg2Ni composite was obviously improved with increasing content of Mg powder in the milling. The discharge capacity of the composites were enhanced with increasing milling time at the beginning of milling, while a decrease was followed. The relationship between discharge capacity and milling time was mainly influenced by the micstructure of composites caused by ball milling.

Abstract:The preparation of metal-ceramic composite material, silver coated BaTiO3 powder, was investigated. The shape of single particle and congeries state were studied with SEM and laser particle size analysis. The existing state of silver on BaTiO3 was also discussed. Silver was deposited on BaTiO3 with chemical deposition method. Protected by surfactant, Ag(NH3)2 was reduced by hydrazine + hydrate, and the composite powder with excellent dispersibility was obtained. The optimal conditions are: concentration of silver 0.1%~ 0.5%, surfactant/ Ag(W/W)20%, the ratio of silver of composite powder < 80%, reaction time 120min and the concentration of hydrazine hydrate 0.8%. The particle size in SEM spectra and EDX analysis suggests that the particle is the composite material with silver coated BaTiO3.

Abstract:用溶膠-凝膠(Sol-Gel)法制備了低介低燒堇青石陶瓷材料。用X射線衍射、熱分析、掃描電鏡等方法研究了該材料的低溫?zé)Y(jié)行為、析晶過程、燒結(jié)性能等。結(jié)果表明，該類材料能夠在900℃下低溫?zé)Y(jié)，其燒結(jié)致密過程主要在750℃～900℃之間進(jìn)行。燒結(jié)體的微觀結(jié)構(gòu)主要由占85％(按體積)、大小為50nm～150nm的α堇青石、少量玻璃相和氣孔組成。該材料具有良好的介電性能(ε≤5，tgδ≤0．001：1GHz)，能夠和銀等電極低溫共燒，是應(yīng)用于高頻片式電感等電子元器件以及高頻陶瓷封裝的理想介質(zhì)材料。

Abstract:Ceramic-like coatings were formed using alternate ultra-narrow pulse microarc oxidation method on alloy Ti6Al4V in Na2SiO3-KOH-(NaPO3)6 aqueous solution. A constant voltage (U=500 V) regime of microarc oxidation was applied to reveal the effect of positive pulse duty cycle on their growth rate, microstructure and phase composition. In order to obtain the optimum process, a constant current density (J=60 mA/cm2) regime combined with the stepped adjusting of positive duty cycle during microarc oxidation process is also proposed. With the positive duty cycle increasing from 4 % to 20 %, the growth rate of the coatings increases and the surface morphology becomes coarser. The as-deposited coatings are mainly composed of anatase and rutile TiO2. With the pulse duration increasing, the content of anatase decreases, while rutile increases and becomes the predominant phase. Considering the microstructure and growing thickness of the coatings, 8 % of positive duty cycle is suitable. When applying the constant current density regime, the growth rate of coatings is significantly increased compared with that by the constant voltage regime. And the morphology of the coatings is obviously improved by using the stepped adjusting of duty cycle furthermore.

Abstract:The brazing-ability of Al2O3P/Cu Base Metal Matrix Composite and Nb with AgCuTi filler metal was studied. The results show that through adding active element Ti to the filler metal, the Al2O3P grains in the brazing seam are decreased or eliminated, and the concentration of Al2O3P grains in the seam is avoided. The ionic bond Al2O3P is transformed in to metalloid bond TiO, so that the matching-ability of the brazing seam substrate and the grain phase is enhanced.