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Abstract:較詳細(xì)地研究了Er2-xCexFe17化合物的結(jié)構(gòu)、磁性和磁熵變。結(jié)果表明,輕稀土Ce的摻入雖然沒(méi)有明顯改變Er2Fe17化合物的相結(jié)構(gòu)及其晶格常數(shù),但改變了Er次晶格與Fe次晶格之間的耦合系數(shù),使仍為T(mén)h2Ni17型六方結(jié)構(gòu)的Er2-xCexFe17化合物的居里溫度可通過(guò)成分微調(diào)使其處在室溫附近。Er2-xCexFe17化合物的λ形(-?SM)-T曲線表明其在居里點(diǎn)附近發(fā)生的相變屬于二級(jí)相變,它使化合物可在較寬溫區(qū)范圍內(nèi)保持較大的磁熵變。Er2-xCexFe17化合物在x=0.05~0.1范圍內(nèi)具有較大的磁熵變,其在2.0T和5.0T外場(chǎng)下的最大磁熵變達(dá)到金屬Gd的40%~50%,且其化學(xué)性質(zhì)穩(wěn)定、制冷溫區(qū)寬、價(jià)格低廉,是一類(lèi)性價(jià)比較高、應(yīng)用潛力較大的新型低場(chǎng)室溫磁制冷工質(zhì)材料。

Abstract:Both CrN hard coatings and CuNiIn solid lubricating films were produced on the titanium alloy substrate by the ion beam enhanced deposition (IBED) technique. The electrochemical corrosion behavior and galvanic corrosion sensitivity of the IBED films and titanium alloy in NaCl solution were studied by using electrochemical measurement methods. The oxidation resistance of the IBED films was evaluated by the elevated temperature static oxidation method. The results show that both the electrochemical corrosion resistance and the oxidation resistance of IBEDD CuNiIn film are better than those of bulk copper. IBED CuNiIn film is contact compatible with titanium alloy substrate in Cl- solution. IBED CrN film has good corrosion resistance compared with the titanium alloy in both Cl- solution and HCl + HF mixed acid solution, it can directly contact with titanium alloy in Cl- solution. The oxidation resistance of CrN film is better than that of the titanium alloy substrate.

Abstract:研究了Ce對(duì)鎂及鎂合金晶粒細(xì)化效果和力學(xué)性能的影響。結(jié)果表明：純鎂結(jié)晶時(shí)易形成粗大的柱狀晶和扇形晶，加入微量稀土元素Ce后，晶粒被明顯細(xì)化，柱狀晶全部轉(zhuǎn)化成等軸晶。在AZ31合金中添加微量稀十元素Ce，晶粒由未細(xì)化前的約300μm下降到約30μm。稀土Ce在鎂及AZ31合金中的固溶度很小，在凝固過(guò)程中固／液界面前沿Ce容易富集引起成分過(guò)冷形成新形核帶導(dǎo)致晶粒細(xì)化。凝固過(guò)程中溶質(zhì)再分配造成固液界面前沿成分過(guò)冷度增大是稀土元素細(xì)化鎂及鎂合金的主要機(jī)理。

Abstract:The absorption and desorption kinetics of the metal hydrogen storage materials are related with the grain sizes to some extent. By means of the absorption and desorption kinetics equations, the effects of the grain sizes of Mg-Ni-MnO2 hydrogen storage materials on their absorption and desorption kinetics are calculated. The results show that the reaction rates of absorption and desorption are greatly different among the Mg-Ni-MnO2 hydrogen storage materials with different particle sizes; the smaller the particle size is, the better the absorption and desorption kinetic. The experimental results of the absorption and desorption kinetics of the Mg-Ni-MnO2 materials prove the kinetic equations to be rational.

Abstract:攪拌摩擦焊接顯微組織的一個(gè)顯著特征就是焊核(Weld Nugget)的形成。采用AZ31鎂合金為母材，通過(guò)金相和透射電鏡分析攪拌摩擦焊接焊核的形成機(jī)制及接頭不同區(qū)域的顯微組織特征，并建立AZ31鎂合金攪拌摩擦焊接的組織演變模型。結(jié)果顯示，緊靠軸肩生成厚度約為37gm～47gm細(xì)密組織層。機(jī)械熱影響區(qū)存在部分動(dòng)態(tài)再結(jié)晶和較明顯的塑性變形晶粒。焊縫底部有一厚約100gm～130gm的粗大組織層。熔核區(qū)的組織比較細(xì)小，沿厚度方向晶粒大小不均勻。同時(shí)提出一個(gè)焊核晶粒細(xì)化的簡(jiǎn)易模型，分析認(rèn)為焊接過(guò)程中熱過(guò)程和熱機(jī)械攪拌作用對(duì)FSW接頭組織的形成起決定性作用。

Abstract:以2090 Ce合金為研究對(duì)象，對(duì)不同時(shí)效時(shí)間的室溫拉伸斷口進(jìn)行了半定量分析，探討了拉伸性能對(duì)斷裂特征的響應(yīng)關(guān)系，重點(diǎn)分析合金分層裂紋的形成過(guò)程。研究表明：2090 Ce合金的斷裂方式以韌窩、分層開(kāi)裂和沿亞晶界開(kāi)裂3種為主，隨時(shí)效時(shí)間的延長(zhǎng)，韌窩、分層開(kāi)裂逐漸減少，沿亞晶界開(kāi)裂比例逐漸加大：分層開(kāi)裂程度與時(shí)效程度有密切關(guān)系：分層開(kāi)裂過(guò)程與試樣內(nèi)部受力狀態(tài)、晶界狀態(tài)有密切關(guān)系。分層最先發(fā)生在試樣中心，隨后在二分之一、四分之一……處反復(fù)發(fā)生，最終將試樣分割成一系列平行的薄板。時(shí)效后期由于亞晶界的弱化，使裂紋傾向沿亞晶界擴(kuò)展，從而抑制分層開(kāi)裂的發(fā)生，同時(shí)導(dǎo)致合金強(qiáng)度，尤其是塑性的下降。

Abstract:The solidification behaviors of nonferromagnetic Al3Ni precipitated phase in Al-8%Ni alloy with a high magnetic field applied have been studied experimentally. It is found that the magnetic field induces the crystals of Al3Ni phase to orient with their c-axes parallel to the field and the long axes of the crystals are perpendicular to their c-axes. There are several Al3Ni congregation planes parallel with each other, which are perpendicular to the field, that is, regular Al3Ni laminated alignment structure is formed in the alloy. In the planes, there are several big Al3Ni congregations, in the inner part of which there are aligned Al3Ni crystals.

Abstract:研究了Zn對(duì)2195鋁鋰合金在不同熱處理狀態(tài)(T8，T6)下的顯微組織和拉伸性能的影響。結(jié)果表明：Zn的存在明顯促進(jìn)了T1相的析出和彌散分布，而且有球形顆粒狀含Zn相析出，使合金強(qiáng)度提高：但Zn的加入不改變2195合金的斷裂機(jī)制，且使合金塑性略有下降。

Abstract:以Cu2O為氧化劑，采用Cu-Al合金粉末內(nèi)氧化及后續(xù)的粉末冶金法制備了Al2O3／Cu復(fù)合材料。并將不同Al2O3含量的試樣進(jìn)行不同變形量的冷拔處理，在氮?dú)獗Ｗo(hù)下進(jìn)行高溫退火處理(700℃～1050℃，1h)。研究了硬度隨退火溫度的變化規(guī)律，觀察了顯微組織。結(jié)果表明：在銅基體中彌散分布著納米級(jí)的Al2O3顆粒：經(jīng)900℃，1h退火后Al2O3／Cu復(fù)合材料的硬度可保持室溫的87％以上；其再結(jié)晶溫度高達(dá)1000℃；變形量和Al2O3含量增加均使硬度提高，但對(duì)軟化和再結(jié)晶溫度影響不大。

Abstract:用K-RE對(duì)Fe-5％V-5％W-5％Mo-5％Cr-3％Nb-2％Co-2％C合金變質(zhì)處理，使凝固組織發(fā)生了明顯的變化，不僅碳化物和基體組織明顯細(xì)化，還出現(xiàn)共晶碳化物斷網(wǎng)現(xiàn)象，產(chǎn)生了較多的小塊狀和顆粒狀碳化物。經(jīng)K-RE變質(zhì)處理Fe-V-W-Mo合金加熱溫度950℃時(shí)，碳化物斷網(wǎng)明顯，加熱溫度1000℃時(shí)，多數(shù)碳化物已斷網(wǎng)，并出現(xiàn)了數(shù)量較多的顆粒狀碳化物，加熱溫度1050℃時(shí)，碳化物網(wǎng)狀組織全部消失，大部分碳化物變成了球狀組織。

Abstract:The effect of rapid quenching on phase structure and hydrogen storage performance of Ti-28V-15Mn-10Cr alloy is investigated. X-ray diffraction (XRD) results show that two phases of BCC and C14 Laves of the as-cast alloy are transformed into a single BCC phase after rapid quenching treatment. The lattice parameters of the alloy increase with increasing of quenching rate. It results in a flatter hydrogen absorption-desorption plateau and a lower hydrogen absorption-desorption plateau pressure. With increasing quenching rate,the activation of Ti-28V-15Mn-10Cr alloy becomes worse.

Abstract:采用熔體快淬及晶化處理工藝制備N(xiāo)d11Fe72-xCo8V1.5CrB7.5(x=0，1)納米晶合金。研究了添加Cr對(duì)合金晶化行為和磁性能的影響。結(jié)果表明，添加Cr提高了軟磁相α-Fe和硬磁相Nd2Fe14B的形成溫度，降低了硬磁相Nd2Fe14B的居里溫度。同時(shí)，添加Cr可細(xì)化兩相晶粒，提高內(nèi)稟矯頑力，從而提高最大磁能積。

Abstract:采用熔體快淬及晶化熱處理工藝制備N(xiāo)d10Fe75Co5Zr3Cr0.5B6 5納米晶合金.快淬薄片(17m·s-1)在710℃,4 min晶化處理后,晶粒尺寸為50 nm～60 nm.該快淬薄片經(jīng)710℃,4min晶化處理后制成的粘結(jié)磁體的磁性能為Br=0.67 T,JHc=707 kA·m-1和(BH)max=74 kJ·m-3.

Abstract:采用SEM和XRD對(duì)Nd13Fe81.5B5.5合金氫化-歧化-脫氫過(guò)程中相結(jié)構(gòu)和組織形貌的變化進(jìn)行了觀測(cè)分析，結(jié)果表明：非受熱的Nd13Fe81.5B5.5合金的吸氫只能在富釹相的品界上進(jìn)行，吸氫的過(guò)程伴隨著熱量的釋放。加熱后的Nd13Fe81.5B5.5合金吸氫不儀沿著Nd13Fe81.5B5.5富釹相品界進(jìn)行，而且也能在其品格內(nèi)進(jìn)行。合金吸氫后牛成物豐相為NdH2.9和α-Fe，還有微量的Fe2B和Fe2Nd，吸氫的過(guò)程伴隨著大量熱的釋放，Nd13Fe81.5B5.5合金的吸氫溫度為700℃，在730℃～800℃的范圍內(nèi)脫氫，在此工藝條件下，能獲得高質(zhì)量的氫化物。

Abstract:通過(guò)采用電弧爐冶煉、HDDR及氮化的方法,對(duì)Sm2Fe17型合金及其氮化物的組織形貌、物相及磁性能進(jìn)行研究發(fā)現(xiàn),多補(bǔ)償添加25%釤可使Sm2Fe17型合金退火后的α-Fe含量小于2%.HDDR后的粉末顆粒表面由蜂窩狀孔洞、密堆積小顆粒及彌散細(xì)小顆粒組成.不同次數(shù)HDDR循環(huán)處理后的主相均表現(xiàn)為與退火后相同的Sm2Fe17結(jié)構(gòu)及易面磁化.HDDR后α-Fe的含量增加,單胞體積膨脹△V/V0.35%.氮化后Sm2Fe17晶格膨脹形成Sm2Fe17Nx主相,α-Fe相膨脹小,氮化增加α-Fe含量,多補(bǔ)償Sm和延長(zhǎng)氮化時(shí)間對(duì)減少α-Fe含量有利.隨著氮化時(shí)間的延長(zhǎng),粉末中的氮含量增加,而且細(xì)粉氮化速度快,其中Sm12.8Fe87.2細(xì)粉氮化速度最快.補(bǔ)償足夠的釤可提高磁性能,從提高矯頑力角度看,多添加25%Sm與40%Sm效果相當(dāng),但從提高剩磁角度看,多添加釤到40%更好.

Abstract:A series of Er2-xPrxFe17 alloys were prepared by the arc melting under the purified argon atmosphere. By means of X-ray diffraction pattern and SQUID magnetometer, the structure and magnetic entropy changes in Er2-xPrxFe17 alloys were investigated. The results show that the crystal structure is Th2Ni17-type hexagonal for Er2-xPrxFe17 alloys; the Curie temperature of Er2-xPrxFe17 alloys can be shifted to the room temperature around by a small adjustment of composition. Magnetic entropy changes (-?SM) near Curie temperature are relatively large in a comparatively wide temperature range for Er2-xPrxFe17 alloys. Er2-xPrxFe17 alloys are provided with great potential in application for the room-temperature magnetic refrigeration

Abstract:較詳細(xì)地研究了Er2-xCexFe17化合物的結(jié)構(gòu)、磁性和磁熵變。結(jié)果表明，輕稀土Ce的摻入雖然沒(méi)有明顯改變Er2Fe17化合物的相結(jié)構(gòu)及其晶格常數(shù)，但改變了Er次晶格與Fe次晶格之間的耦合系數(shù)，使仍為T(mén)h2Ni17型六方結(jié)構(gòu)的Er2-xCexFe17化合物的居里溫度可通過(guò)成分微調(diào)使其處在室溫附近。Er2-xCexFe17化合物的λ形(-△SM)-T曲線表明其在居里點(diǎn)附近發(fā)生的相變屬于二級(jí)相變，它使化合物可在較寬溫區(qū)范圍內(nèi)保持較大的磁熵變。Er2-xCexFe17化合物在x=0．05-0．1范圍內(nèi)具有較大的磁熵變，其在2．0T和5．0T外場(chǎng)下的最大磁熵變達(dá)到金屬Gd的40%～50％，且其化學(xué)性質(zhì)穩(wěn)定、制冷溫區(qū)寬、價(jià)格低廉，是一類(lèi)性價(jià)比較高、應(yīng)用潛力較大的新型低場(chǎng)室溫磁制冷工質(zhì)材料。

Abstract:采用二氧化硅／碳化硅復(fù)合靶，用射頻磁控共濺射技術(shù)和后高溫退火的方法在Si(111)襯底上制備了碳化硅納米顆粒／二氧化硅基質(zhì)(nc-SiC／SiO2)鑲嵌結(jié)構(gòu)薄膜材料，用X射線衍射(XRD)，傅里葉紅外吸收(FTIR)，掃描電子顯微鏡(SEM)和光致發(fā)光(PL)實(shí)驗(yàn)分析了薄膜的微結(jié)構(gòu)以及光致發(fā)光特性。結(jié)果表明：樣品薄膜經(jīng)高溫退火后，部分無(wú)定形SiC發(fā)生晶化，形成β-SiC納米顆粒而較均勻地鑲嵌在SiO2基質(zhì)中。以280nm波長(zhǎng)光激發(fā)薄膜表面，有較強(qiáng)的365nm的紫外光發(fā)射以及458nm和490nm處的藍(lán)光發(fā)射，其發(fā)光強(qiáng)度隨退火溫度的升高顯著增強(qiáng)，發(fā)光歸結(jié)為薄膜中與Si-O相關(guān)的缺陷形成的發(fā)光中心。

Abstract:Thin VOx films were prepared by magnetron sputtering onto p-Si(100) substrates. X-ray diffraction (XRD), atomic force microscope(AFM) and four-point probe method were employed to study the influence of the preparation parameters on the phase composition and resistance-temperature characteristic of VOx. The thermal stability of the films was also investigated. The results show that VOx films prepared by this method have relatively high temperature coefficient of resistance (TCR) and perfect thermal stability. They are promising to be used as thermal sensor materials in the microbolometer.

Abstract:應(yīng)用循環(huán)伏安法研究了聚合前驅(qū)體熱分解法制備的Ti／TiO2膜電極在pH=1的H2SO4溶液和pH=14的NaOH溶液中的電化學(xué)活化表面積。結(jié)果表明，相同條件下制備的Ti／TiO2膜電極在H2SO4溶液中的伏安電荷容量要遠(yuǎn)遠(yuǎn)高于在NaOH溶液中的伏安電荷容量，電極在不同pH值溶液中的內(nèi)電化學(xué)活化表面積又遠(yuǎn)遠(yuǎn)高于外電化學(xué)活化表面積。因此電極表面活化表面積的大小與電極的結(jié)構(gòu)以及溶液的pH值有關(guān)。

Abstract:以Ce(NO3)3·6HzO為鈰源,(NH4)2CO3·H2O為沉淀劑,并加入一定量表面活性劑PEG4000,采用液相沉淀法制備前驅(qū)體Ce2(CO3)3·H2O,前驅(qū)體經(jīng)熱處理合成納米CeO2.根據(jù)XRD線寬法研究了納米CeO2熱處理過(guò)程的晶粒生長(zhǎng)動(dòng)力學(xué),結(jié)果表明隨焙燒溫度升高,CeO2晶粒尺寸顯著增大;300℃下焙燒時(shí)間對(duì)CeO2晶粒尺寸影響不明顯,700℃下CeO2晶粒隨焙燒時(shí)間延長(zhǎng)而長(zhǎng)大,且焙燒初期粒徑增長(zhǎng)較快,超過(guò)180 min后增長(zhǎng)速率變慢;700℃時(shí)CeO2晶粒生長(zhǎng)指數(shù)為5,即符合5次方動(dòng)力學(xué)方程,晶粒生長(zhǎng)速率常數(shù)為1.986 5×104 nm5/min;由于納米尺寸效應(yīng),使得CeO2晶粒生長(zhǎng)活化能在低溫區(qū)和高溫區(qū)不同,低于400℃時(shí)為25.64 kJ/mol,高于400℃時(shí)為87.64 kJ/mol;認(rèn)為熱處理過(guò)程CeO2的晶粒生長(zhǎng)為擴(kuò)散生長(zhǎng)機(jī)制.

Abstract:以TiCl4和O2為反應(yīng)體系，采用高頻等離子化學(xué)氣相沉積(HF-PCVD)法制備了晶化完整的銳鈦和金紅石混晶型TiO2納米晶，球形體的晶粒分散性良好，分布較為均勻：研究了控制粒徑大小和晶相組成的關(guān)鍵反應(yīng)條件。XPS，TEM，XRD結(jié)果顯示：增加TiCl4進(jìn)料量、延長(zhǎng)停留時(shí)間均利于銳鈦相向金紅石相轉(zhuǎn)化，但粒徑有所增大：添加A1C13使金紅石相含量較未摻雜時(shí)有較大幅度提高，且粒徑隨摻鋁量增加而減小。本實(shí)驗(yàn)條件下，TiO2納米晶的粒徑為25nm～60nm，金紅石相含量在12．O％～53．6％間可控。

Abstract:The compound nanoparticle of TiO2 doped with rare earth ions Y3+ was prepared under the optimum condition of preparing nanoparticle TiO2 with sol-gel processing. TiO2 and doped TiO2 were both characterized by XRD, TEM and DRS. The experiments of photocatalytic degradation phenol was used to investigate the activity of Y3+/TiO2 and its effect on the reaction process. The XRD results show that TiO2 and doped TiO2 are the mixture of anatase and rutile, and the ratio of anatase to rutile was 3:1; doping can retard the development of grain size of TiO2 and decrease the diameter of TiO2 to about 10nm. DRS are used to investigate the ability of absorbing light and the shift of spectrums of TiO2 and doped TiO2. The results show doping makes the light absorption increase and the spectrums of 1.5Y3+/TiO2 and 3.0Y3+/TiO2 both show red shift. The results of experiment of photocatalytic degradation of phenol show that the optimum doping content is wt(Y3+)=1.5%, and the photocatalytic degradation ratio of phenol increases by about 20% compared with the undoped TiO2.

Abstract:在25℃～100℃的溫度范圍內(nèi),測(cè)定了PdY8.5Ru0.19合金吸放氫、氘的P-C-T曲線.與純鈀相比,合金的P-C-T曲線坪區(qū)變窄,坪壓降低,有顯著的同位素效應(yīng),但遲滯效應(yīng)較小.合金吸放氫氘的P-C-T曲線可擬合成p=A(er/B-1)形式.吸氘熱焓為-13.9 kJ/mol·D2,熵變?yōu)?9.4 J/mol K·D2.進(jìn)行了25℃下合金吸氫、氘速率的測(cè)量,合金吸氫、氘速率常數(shù)分別為KH=2.39×10-4 mol·s-1,KD=1.16×10-4 mol·s-1.而且合金的氫化過(guò)程用漸進(jìn)轉(zhuǎn)化模型描述.

Abstract:Zr-based metallic-glass matrix composites, which were reinforced by continuous tungsten fibers, were prepared by melinfiltration casting. The interface reaction and diffusion were analyzed by using X-Ray diffraction, SEM and EPMA. The influence of Nbcontent of the matrix alloy on the interface reaction and diffusion was also investigated. The results illustrate that for the Zr55Al10Ni5Cu3matrix composites an interface eutectoid reaction between W fiber and Zr in the liquid phase takes place and a W5Zr3 phase is formed athe interface. The interface moves to the direction of the liquid phase. For the matrix alloy containing Nb, the addition of Nb in the liquidcauses a significant change of interface reaction. Nb in the liquid phase exhibits a preferential adsorption at the surface of the W fiber, thusreduces the adsorption of Zr atom in the liquid phase at the surface of the W fiber. The activity of absorbed Zr at interface is decreasedand depresses the interface eutectoid reaction between W fiber and liquid. In this case the interface is a simple diffusion layer only. At thesame time the diffusion coefficient of Zr in the W is decreased by Nb addition and the interface moves to the direction of W fiber.

Abstract:To study SiC and other material joining, the wettability of Cu-Al-Si-Ti brazing alloys on silicon carbide was investigated by sessile drop method. It was found that the Ti content and the wetting temperature affected greatly the contact angle. The interface of brazing alloys/silicon carbide was observed and analysed by SEM and XRD. The result indicated that the interface consisted of two layers, e.g. one of them was a thin interface layer with TiC, the other was a thick interface transition layer with Cu-more content and Ti-less content. The diffusion of element Cu determines the property of transition layer. This kind of brazing alloy is a good candidate for the high temperature brazing silicon carbide.

Abstract:研究了PLZT鐵電陶瓷的電疲勞特性。結(jié)果表明：在加上極化電場(chǎng)以后，相對(duì)于未疲勞試樣，電疲勞試樣中沿著電場(chǎng)方向翻轉(zhuǎn)的電疇較少，沿偏離電場(chǎng)方向的電疇較多。SEM分析表明疲勞前樣品的斷裂模式主要為穿晶斷裂，而疲勞后主要為沿晶斷裂。利用原位XRD分析得出樣品在交流電場(chǎng)下由90。疇變導(dǎo)致的疇變應(yīng)變高達(dá)0．1％，這種反復(fù)高疇變應(yīng)變?cè)斐傻难鼐⒘鸭y是造成疲勞試樣電疇沿電場(chǎng)方向翻轉(zhuǎn)減少的主要原因，并最終導(dǎo)致了鐵電陶瓷的電疲勞。

Abstract:The feasibility of reduced-friction coating against U-Nb alloy made by plasma spray technique was investigated. Sn soft coating, Sn/ ZrO2 dual coating, Sn and ZrO2 mixing coating and ZrO2 hard coating were prepared by plasma spray technique. The sliding friction behavior of these coatings against U-Nb alloy was evaluated. The friction characteristic of Sn coating is similar to Sn/ ZrO2 dual coating and its friction coefficient is the lowest among the four coatings. Friction coefficient of ZrO2 coating, into which Sn was added, is decreased little, while friction coefficient of ZrO2 hard coating is stabilized at high value with the increase of sliding number of cycles. ZrO2 coating by plasma spray technique plays no role in reducing friction against U-Nb alloy. Plough is the main friction mechanism of these coatings.

Abstract:研究了鈦合金粉末的溫壓成形行為。結(jié)果發(fā)現(xiàn)，在同一壓制壓力下，鈦合金粉末的生坯密度均在140℃左右達(dá)到最大值，高于或低于這一溫度，生坯密度反而降低。在壓制壓力為500MPa下，溫壓成形的脫模力比室溫成形的脫模力降低27．7％。同時(shí)，溫壓成形較室溫成形改善了鈦合金件的顯微組織。

Abstract:研究了在1260℃燒結(jié)時(shí),燒結(jié)時(shí)間對(duì)Ti-6Al-4V燒結(jié)坯力學(xué)性能的影響.結(jié)果表明平均晶粒尺寸為45 μm的氫化-脫氫粉末樣品在1 260C燒結(jié)3 h～6 h,其相對(duì)密度為95.6%～96.7%、拉伸強(qiáng)度648 MPa～686 MPa、屈服強(qiáng)度526 MPa～615 MPa,但延伸率僅小于4%.90%氣霧化(晶粒尺寸為32.5 μm)和10%氫化-脫氫混合粉末樣品在1 260℃燒結(jié)2 h～6 h,其相對(duì)密度大于95%、拉伸強(qiáng)度800 MPa～848 MPa、屈服強(qiáng)度712 MPa～762 MPa、延伸率7.4%～9.5%.混合粉末樣品的力學(xué)性能幾乎達(dá)到美國(guó)ASTM粉末冶金的標(biāo)準(zhǔn).

Abstract:利用自行丌發(fā)的Gasar裝置，成功制備了具有規(guī)則氣孔分布的藕狀多孔金屬M(fèi)g，并研究了鑄型預(yù)熱溫度和氣體壓力等工藝參數(shù)對(duì)氣孔率、氣孔大小和分布的影響。結(jié)果表明：提高鑄型的預(yù)熱溫度可以完全消除鑄錠側(cè)向的無(wú)氣孔金屬殼：隨著氫氣壓力的增大，鑄錠的氣孔率和氣孔平均直徑都在減小、氣孔的尺寸分布均勻性提高。

Abstract:Specimens of MB15 magnesium alloy reinforced with SiC whiskers (SiCw/MB15) were fabricated using powder metallurgy route (PM). The influence of SiCw on the 150oC aging behavior of MB15 alloy was investigated by microhardness-testing, and SEM, TEM and tensile tests studied the influence of powder-mixing methods on the distribution of SiCw and the mechanical properties of SiCw/MB15. The results reveal that the double peaks exist in the age-hardening curves of both the unreinforced and the reinforced MB15 alloy, and the addition of SiCw can accelerate the age-hardening process of MB15 alloy apart from increasing its micro- hardness, moreover, the mechanical properties of SiCw/MB15 composite are significantly influenced by powder-mixing methods of PM.

Abstract:以噴霧干燥法制備的（W，Ni，F(xiàn)e)復(fù)合氧化物粉末為原料，采用700℃，保溫90min的條件進(jìn)行還原；研究了不同稀土Y含量對(duì)還原制備納粹級(jí)W-Ni-Fe復(fù)合粉末性能的影響；采用XRD及高倍SEM分別對(duì)所制備的復(fù)合粉末進(jìn)行了物相分析、晶粒尺寸測(cè)試和形貌觀察；并對(duì)的制得復(fù)合粉末的Fsss粒度、比表面進(jìn)行了測(cè)定與分析。結(jié)果表明：不加稀土Y時(shí)還原粉末由W和7-（Ni，F(xiàn)e)兩相組成，添加一定量稀土Y的還原粉末有W，7-（Ni，F(xiàn)e)和Y（Ni0.75W0.25)O3三相組成；當(dāng)Y的質(zhì)量分?jǐn)?shù)在0%-0.8%范圍內(nèi)（占90W-Ni-3Fe復(fù)合粉末的質(zhì)量分?jǐn)?shù)），隨著Y含量的增高，粉末dBET粒度由96.6nm降到45.2nm，粉末Fsss粒度由0.64μm降到0.28μm，粉末晶粒尺寸由26.1nm降到19.8nm；未添加稀土Y時(shí)粉末顆粒為球形，添加一定量的稀土Y，粉末顆粒變?yōu)榻蛐位蚨嗝骟w；添加一定量的稀土Y不僅可以有效地掏晶粒的長(zhǎng)大，還可以在一定程度上提高粉末的分散性。

Abstract:80.7W-13.2Ni-6.1Fe(atom percent)tungsten heavy alloys were prepared by mechanical alloying (MA). The volume fraction of the remanent crystalline W in the as-milled materials and the W atom percent in amorphous phase were measured using a method similar to the internal standard method and the route of amorphization. The mechanism of the amorphous phase forming in the process of milling was analyzed. The results show that the crystalline size of tungsten reaches 11 nm~20 nm after milling for 60 h. Ni dissolves in crystalline W and then amorphization of W supersaturated solid solution occurs after milling for 20 h. Forming of the supersaturated solid solution is attributed to dissolving of the small particles with large stored energy into W continuously and the critical size of the Ni particles which can dissolve in the W is 3nm calculated based on the stored energy model. During milling, the volume fraction of the remanent crystalling W is decreased, and the W contents in the amorphous phase remain content, approximately 63W-37Ni(Fe), due to the Fe contamination dissolving into W continuously.

Abstract:采用Nb與Nb2O5固-固反應(yīng)制備低價(jià)鈮氧化物粉末,用正交試驗(yàn)法及方差分析對(duì)制備低價(jià)鈮氧化物電解電容器陽(yáng)極的工藝條件進(jìn)行了優(yōu)化。所研制的電容器陽(yáng)極比容69500μF·V·g-1、損耗11.25%、漏電流(K值)1.8×10-4μA·μF-1·V-1,優(yōu)于FTa16-300電容器鉭粉國(guó)家標(biāo)準(zhǔn)(GB/T3136-1995)。

Abstract:為了改善空氣電極的電催化性能，提高鋅空氣電池的放電電流密度。采用溶膠．凝膠法制備了鋅空氣電池用催化劑LiMn2-xCoxO4。通過(guò)X射線衍射(XRD)、粒徑分布、穩(wěn)態(tài)電流．電壓極化曲線等方法，研究了所得催化劑的結(jié)構(gòu)及其電催化性能。并與高溫固相反應(yīng)法所得催化劑的結(jié)構(gòu)與電催化性能作了對(duì)比。結(jié)果表明，當(dāng)反應(yīng)體系的pH值為7～8、溫度為80℃時(shí)所得凝膠再經(jīng)600℃下保溫處理12h，可以得到具有最高催化活性的催化劑；溶膠．凝膠法合成催化劑的粒徑較小，主要集中在1μm～4．5μm的范圍內(nèi)，粒度分布較窄，而高溫固相反應(yīng)法合成催化劑的粒徑較大，主要集中在5μm～30μm的范圍內(nèi)。粒度分布較寬：2種方法所得的催化劑具有完全相同的晶態(tài)結(jié)構(gòu)；溶膠．凝膠法和高溫固相反應(yīng)法催化劑的空氣電極在-0．6V極化電位下的電流密度分別達(dá)到250mA／cm^2和210mA／cm^2，前者比后者的較高。

Abstract:利用溶膠-凝膠法在SiO2凝膠體系中制備了納米級(jí)的鍶鐵氧體磁性微粒，該磁性微粒組成為3O％SrFe12O19和70％SiO2(質(zhì)量百分含量)。對(duì)該微粒進(jìn)行了XRD分析，利用VSM對(duì)樣品進(jìn)行了磁性能研究。研究表明，相對(duì)于共沉淀法制備的純鍶鐵氧體微粒，在SiO2凝膠體系中制備的SrM微粒仍保持為六方磁鉛石型結(jié)構(gòu)，但是粒徑明顯降低，850℃結(jié)樣品的粒徑約為31nm；且內(nèi)稟矯頑力Hc有了顯著的提高，850℃燒結(jié)樣品的內(nèi)稟矯頑力達(dá)到518．4kA／m，而比飽和磁化強(qiáng)度則有所下降。并對(duì)其磁性能變化的原因進(jìn)行了分析。

Abstract:摘要：采用固相燒結(jié)工藝制備了SrBi4Ti4O15(SBTi)／Ag鐵電復(fù)合材料，通過(guò)X射線衍射、光學(xué)金相顯微鏡和掃描電子顯微鏡對(duì)材料的組成和微觀結(jié)構(gòu)進(jìn)行了研究，并測(cè)量樣品的介電溫度譜。結(jié)果表明：復(fù)合材料是由SBTi和Ag兩相組成。微量金屬Ag的加入使SBTi鐵電陶瓷的燒結(jié)溫度從1120℃降低到950℃以下：可以適當(dāng)提高鐵電陶瓷從室溫到200℃的介電常數(shù)，但對(duì)材料的介電損耗影響很小。同時(shí)Ag的加入壓抑了介電溫度曲線上的介電常數(shù)的Curie峰。

Abstract:Various processes of the Mo/Si thin films deposited on Si (001) substrates by RF magnetron sputtering technique were carefully investigated and the MoSi2 thin film with the single tetragonal phase and low resistivity was successfully prepared. X-ray diffraction, scanning electrical microscopy, atomic force microscope and Four-probe resistance meter were used to determine their structures, surface morphologies and electrical properties. Results show that the electrical property of the Mo/Si films depends strongly upon their microstructure and the phase composition. The as-deposited film mainly belongs to amorphous. After annealing at the high temperature. The great change of the film crystallization structure takes place, and its phase composition varies with the as-deposited processes. The effect of the crystallization enhances obviously, and the square resistance of the film drops greatly.

Abstract:Hexagonal GaN micro-ribbons were synthesized through nitriding Ga2O3 films under flowing ammonia. Ga2O3 films were deposited on the Ga-diffused Si (111) substrates by radio frequency (r.f.) magnetron sputtering. X-ray diffraction (XRD), scanning electron microscopy (SEM), selected area electron diffraction (SAED); X-ray photo electronic spectrometer (XPS) and photoluminescence (PL) spectroscopy were used to characterize the structure, surface morphology, composition and optical property of the synthesized samples. SEM images show that GaN micro-ribbons with 100-300rim in diameter are randomly distributed on the uniform films. XRD, XPS and SAED analysis suggest the micro-ribbons are polycrystalline GaN with hexagonal structure and preferentially grow in the [001] direction. The PL spectrum has a remarkable blue shift compared with the reported values of bulk GaN, which might be ascribed to quantum confinement effects.

Abstract:采用射頻磁控濺射法在玻璃襯底上低溫制備出了鎵摻雜氧化鋅(ZnO:Ga)透明導(dǎo)電膜,研究了真空退火對(duì)薄膜結(jié)構(gòu)、電學(xué)和光學(xué)特性的影響。結(jié)果表明:真空退火后,薄膜結(jié)構(gòu)得到明顯改善,電阻率由退火前的1.13×10-3?·cm下降到5.4×10-4?·cm,在可見(jiàn)光區(qū)的平均透過(guò)率也由未退火前的83%提高到退火后的90%以上。

Abstract:以錫鹽和金屬銦為原料采用膠體法制備ITO前驅(qū)物漿料，通過(guò)提拉法在鍍有SiO2薄層的浮法玻璃基片上制備透明導(dǎo)電ITO薄膜。用TEM測(cè)定ITO前驅(qū)物漿料顆粒大小；用XRD、SEM、AES分別對(duì)ITO薄膜的結(jié)構(gòu)和表面形貌進(jìn)行表征；用分光光度計(jì)和四探針電阻儀檢測(cè)ITO薄膜光電性能。結(jié)果表明：ITO前驅(qū)物漿料的顆粒粒徑為2nm～15nm，具有較好的分散性和穩(wěn)定性：ITO薄膜厚度越大，方電阻越小，平均透過(guò)率下降；ITO薄膜在波長(zhǎng)為360nm～800nm區(qū)的透過(guò)率隨膜厚增加有不同的影響；退火溫度越高，膜方電阻越低；當(dāng)膜厚為300nm、退火溫度600℃時(shí)，膜方電阻達(dá)到2581Ω／n，其透過(guò)率在波長(zhǎng)550nm處達(dá)到89．6％，且薄膜表面平整。

Abstract:制備了一種新的Er^3 ／Tm^3 /Yb^3 共摻氧鹵碲酸鹽玻璃。研究了基質(zhì)玻璃的熱穩(wěn)定性能、Raman光譜和上轉(zhuǎn)換發(fā)光。發(fā)現(xiàn)：氧鹵碲酸鹽玻璃具有好的熱穩(wěn)定性能和低的聲子能量，在980nmLD激發(fā)下，可同時(shí)觀察到明顯的藍(lán)色(476nm)、綠色(530nm和545nm)和紅色(656nm)上轉(zhuǎn)換發(fā)光。上轉(zhuǎn)換藍(lán)光(476nm)是由于Tm^3 離子1^G4→3^3H6躍遷，上轉(zhuǎn)換的綠光(530nm和545nm)是由于Er^3 離子2^H11/2→4^I15／2和4^S3/2→4^I15/2躍遷，上轉(zhuǎn)換紅光(656nm)是由于Er^3 離子4^F9/2→4I15/2躍遷。