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Abstract:The crystallization of amorphous alloys predestinates the microstructure and magnetic properties of the melt spun nanocomposite rare earth permanent magnets. Obeying the nucleation regularity, the model of the crystallization of amorphous alloys,namely, continually and explosively nucleation and growth. is put forward. The main factors affecting it were analyzed, such as melt-spun speed, the addition of alloys and the annealing sequence with or without the applied magnetic field, Especially, the re-distribution of the alloys during crystallization. On the bases, the ideas to gain ideal grain structure were discussed, for example, refining the grains by decomposition of metastable phase.

Abstract:The waste material of precious metals is an important secondary resource. How to increase the utilization of these waste materials and treat them innoxiously is an important problem, and have drawn a wide attention around the world. In this paper, the characterization, origination, pretreatment methods of waste materials of precious metals and the recovering technology of gold, silver, platinum and palladium from above waste materials have been reviewed. Several suggestions about innoxious treatment on the waste materials of precious metals have been proposed.

Abstract:Thermoelectric materials used for the conversation between thermal energy and electric energy make it possible to manufacture no pollution, no mechanical moving and high effective equipments which can be used for generate electricity and refrigeration. with the increase of environment problems and energy consumption, thermoelectric materials have been drawing more and more attention. The R&D of various thermoelectric materials are introduced and reviewed.

Abstract:分別以Miedema坐標(biāo)、合金自擴(kuò)散激活能ΔHs與形成焓ΔHf為參數(shù)坐標(biāo)，將多元合金分解為若干相應(yīng)的二元合金疊加，對有實驗結(jié)果的128個二元和153個多元機(jī)械合金化(MA)非晶合金的形成規(guī)律進(jìn)行了研究。結(jié)果：以上2種坐標(biāo)中，分別可由一直線或曲線將非晶形成與非形成區(qū)分割，方程為：Miedema坐標(biāo)，二元系，y=2．8600x 0．22；多元系，y=2．7900x 0．27，總區(qū)分率均為80％：ΔHs～ΔHf坐標(biāo)，二元系，y=0．0005x^2 0．20x-23；多元系，y=0．0005x^ 0．21x-25，總區(qū)分率分別為85％和83％。合金包含過渡族金屬、涵蓋非過渡族金屬及類金屬，并擴(kuò)展至多元系，同時與已有定性以及半定量結(jié)果進(jìn)行了比較。

Abstract:The effects of the binder composition, powder loading, thermal properties of feedstocks, and the injection molding parameters on the compact shape retention for metal injection molding 17-4PH stainless steel were investigated. HDPE is more effective as a second component of the wax-based binder to retain compact shape than EVA due to its higher pyrolytic temperature and higher heat of fusion. The compact distortion decreases with the increase of powder loading, molding pressure and molding temperature. There exists a best process condition, including powder loading, molding pressure and molding temperature. Under this process condition, the lowest percentage is there of distorted compacts.

Abstract:The surfaces of Zr-Ti hydrogen storage alloys are modified with methods such as chemical plating of nickel or cobalt, mechanical mixture, ball grinding and so on. XRD shows that the alloy has the trend to form micro-crystals with the content of coating nickel increasing, and long grinding time leads to dispersion of diffraction peaks of alloys. When the discharge current density is 60mA.g-1, the initial capacity of the alloy electrode plated Ni 15wt% is 130 mAh.g-1 more than that of untreated alloy. The alloy is activated absolutely after 6 cycles ~8 cycles, and the max discharge capacity can reach 400 mAh.g-1. The discharge capacity of alloy electrode with 5% Co can be up to 390 mAh.g-1. Anti-discharge ability increases with the percentage of Ni plated. The activation behavior of hydrogen storage alloys is also improved by ball grinding, and the max discharge capacity can reach 450 mAh.g-1. Mechanical mixture can only increase initial capacity without any improvement of max discharge capacity.

Abstract:This paper analyzed the flow of working medium in extrusion by an athletic differential equation of viscous fluid and discussed the influence of the viscosity on Hot Hydrostatic Extrusion(HHE). Extrusion force of HHE can be minimized and the disfigurement of extrusion products can be avoided when the viscosity of the medium is proper. A mathematics formula for the viscosity of working medium is given important theoretic foundation for HHE.

Abstract:利用有限元法，采用彈塑性理論對Al2O3陶瓷／Nb接頭的應(yīng)力場進(jìn)行了數(shù)值模擬。得出了接頭部位應(yīng)力σx，σy和τxy的分布狀態(tài)，研究發(fā)現(xiàn)在當(dāng)接頭界面結(jié)合良好時在界面附近的陶瓷側(cè)的殘余主應(yīng)力(σ1)出現(xiàn)極大值，裂紋最有可能從此處開啟，然后在殘余主應(yīng)力(σ2)的作用下向陶瓷內(nèi)部延伸。

Abstract:通過磁性測量和X-射線衍射研究了Gd2(Co，Al)17化合物的結(jié)構(gòu)和磁晶各向異性。當(dāng)x≤4時，樣品具有菱方Th2znl7型結(jié)構(gòu)，x=5時，具有六方CaCu5型結(jié)構(gòu)。隨著Al濃度增加，晶格常數(shù)和單胞體積單調(diào)增大，而居里溫度和自發(fā)磁化強(qiáng)度近似線性地減?。辉趚≥l時，觀察到Co亞點陣的磁晶各向異性變號，室溫易磁化方向由易面轉(zhuǎn)變?yōu)橐纵S，且易軸各向異性場和各向異性常數(shù)隨Al原子濃度增加出現(xiàn)極大值；基于補(bǔ)償溫度(65K)下自由粉末顆粒的磁化曲線，導(dǎo)出了亞點陣間的分子場系數(shù)和Gd-co交換耦合常數(shù)，結(jié)果表明，Al原子對Gd-Co交換耦合作用的影響較小。根據(jù)Al原子在Co亞點陣4種晶位的擇優(yōu)占位，分析了磁晶各向異性的演變。

Abstract:基于離散格點形式的微擴(kuò)散方程(Langevin方程)和非平衡自由能函數(shù)，編制了引入原子間相互作用能變化的Al3Li(δ′)相沉淀原子層面計算機(jī)模擬程序。該程序包容亞穩(wěn)區(qū)到失穩(wěn)區(qū)的全部溫度、成分范圍，孕育期至粗化的全過程，可以處理與時間相關(guān)的過程問題。開展了不同原子間相互作用勢下原子圖像、序參數(shù)的計算機(jī)模擬，進(jìn)而探討了最近鄰原子相互作用能(W1)對有序相沉淀的影響機(jī)制。探明過渡區(qū)合金先發(fā)生等成分有序化，后進(jìn)行失穩(wěn)分解；隨W1的增大，有序相沉淀的孕育期縮短，單相有序疇數(shù)量增多，面積減小，合金達(dá)到最大有序化的時間早，所能達(dá)到的最大有序化程度大。W1值較大，會促進(jìn)合金有序化和原子簇聚，阻礙無序相的形成。

Abstract:通過熱力學(xué)平衡相計算方法并采用相應(yīng)的Ni基數(shù)據(jù)庫，對1種新型高鉻的Ni-Cr基GH648合金成分對平衡相析出的影響規(guī)律進(jìn)行系統(tǒng)研究。結(jié)果認(rèn)為GH648合金析出的主要平衡相為α-Cr，γ′相和M23C6碳化物(主要為Cr23C6)，并進(jìn)一步計算了合金成分對這些相的析出行為及合金初熔點和終熔點的影響規(guī)律。計算結(jié)果表明，Cr含量主要影響α-Cr的析出量及開始析出溫度，并影響合金的初熔點，對以Cr為主的M23C6的析出行為沒有明顯影響。C顯著影響碳化物的析出量，而Al，Ti增加顯著增加γ′相的析出量和開始析出溫度。

Abstract:The structure of K2Ti6O13 nanowires has been investigated using both the Rietveld powder diffraction profile fitting technique and high resolution transmission electron microscopy (HRTEM) image simulations. the Rietiveld analysis show that the nanowires had a monoclinic structure of the space group C2/M. The good agreement between the experimental and simulated images confirms that the nanowires is indeed K2Ti6O13 nanowire. HRTEM conclusions agree with refinement results obtained from experimental XRD data. The nanowires grow out mainly along the [010] direction.

Abstract:彈性變形范圍內(nèi),在采用三維有限元模型分析了顆粒增強(qiáng)Mg基復(fù)合材料(PRMMCs)中,顆粒的分布形態(tài)對材料微區(qū)力學(xué)狀態(tài)的影響。結(jié)果表明,在保持顆粒長徑比(2:1)和顆粒間距(d)不變的情況下,隨著θ的變化,不存在顆粒斷裂的危險,材料的主要失效方式為界面脫離和基體開裂。增強(qiáng)體相對夾角θ=15o時的結(jié)果優(yōu)于其它情況,這更有利于充分發(fā)揮材料的性能。

Abstract:為了推進(jìn)從俄羅斯引進(jìn)的田灣VVER-1000型核電站用Zr-1Nb合金燃料包殼和端塞棒材的國產(chǎn)化進(jìn)程，研究了焊接及隨后的真空熱處理對Z4-1Nb合金抗360℃，18．6MPa水和500℃，10.3MPa蒸汽腐蝕性能的影響。實驗結(jié)果表明焊接嚴(yán)重惡化Zr-1Nb合金在2種介質(zhì)中的腐蝕抗力，主要是因為焊區(qū)中出現(xiàn)了粗大的馬氏體組織；隨后的真空退火對腐蝕抗力的影響取決于退火溫度和腐蝕實驗溫度。但即使在最佳溫度退火也不能使焊接態(tài)的腐蝕抗力恢復(fù)到非焊接態(tài)的水平。

Abstract:通過等溫壓縮特性及微觀組織演變研究，提出了有效的γ-TiAl基合金晶粒細(xì)化方法。研究發(fā)現(xiàn)，如果γ-TiAl合金錠具有一定的細(xì)晶組織便可以在(α2 γ)2相區(qū)完成等溫變形而不產(chǎn)生裂紋。動態(tài)再結(jié)晶和靜態(tài)球化數(shù)量的增加是提高γ-TiAl合金變形能力的主要原因。將等溫變形的模擬鍛件在不同相區(qū)進(jìn)行熱處理獲得了具有細(xì)小尺寸的3種(全片層、近片層和雙態(tài))組織。

Abstract:Hexagonal wurtzite GaN materials with nano-structure have been fabricated on Si (111) substrates via ammoniating ZnO/Ga2O3 films at different temperatures. ZnO layers and Ga2O3 films were deposited in turn on Si (111) substrates by radio frequency (r.f.) magnetron sputtering before the ammoniating process. The structure and composition of GaN crystal were studied by X-ray diffraction(XRD) and fourier transform infrared spectrophotometer(FTIR).The morphology of the samples was studied by scanning electron microscopy (SEM).Through the analyses of the measurement results , a conclusion can be drawn that hexagonal wurtzite GaN with nano structure was grown on Si (111) substrates with the assistance of the volatilization of ZnO, and the ammoniating temperature has a great effect on the fabrication of GaN nano materials with this method.

Abstract:研究了不同能量界面動態(tài)共混過程中的界面反應(yīng)及其對沉積在GCr15和45鋼基體的IBAD CrN薄膜結(jié)合強(qiáng)度的影響。用AFM和GDOES分析了不同能量共混界面的形貌和成分。用循環(huán)滾動接觸法使薄膜在膜基最薄弱處產(chǎn)生剝落，用以分析界面反應(yīng)產(chǎn)物，同時對膜基結(jié)合強(qiáng)度加以評價。用SEM，EDAX和XPS分析了滾動接觸疲勞試驗后的疲勞剝落區(qū)的形貌、成分及結(jié)構(gòu)。結(jié)果表明40kV共混后的界面粗糙度高并出現(xiàn)了碳含量的升高，而20kv時界面碳含量和基體差不多。基體碳化物在離子轟擊引起的熱峰效應(yīng)的作用下發(fā)生分解，而對基體和碳化物的選擇濺射導(dǎo)致了碳含量的升高以及粗糙度的增加。分解后的碳以石墨態(tài)的形式存在。在滾動接觸疲勞試驗時循環(huán)載荷的作用下，界面處的石墨相當(dāng)于孔洞引起應(yīng)力集中。疲勞裂紋起始于界面石墨富集處表明它是引起結(jié)合強(qiáng)度差的主要原因。

Abstract:研究了放電等離子燒結(jié)(SPS)納米WC-10%Co-0.8%VC硬質(zhì)合金的致密化機(jī)理,并與真空燒結(jié)的制品顯微組織及性能進(jìn)行對比。SPS特殊的直流脈沖電壓使燒結(jié)中蒸發(fā)-凝固、塑性流動、表面擴(kuò)散等過程得到加強(qiáng),使制品在低溫下快速致密,有效抑制了晶粒的長大,如在1200℃燒結(jié)5min的制品平均晶粒尺寸<100nm。與真空燒結(jié)相比,SPS可以使制品在低溫、短時間內(nèi)獲得高密度、高硬度,如1300℃燒結(jié)3min,制品相對密度達(dá)97.7%,HV30比相同燒結(jié)溫度下真空燒結(jié)30min的相對密度92.8%的制品高近16.4%。SPS燒結(jié)溫度降低至1200℃,雖然密度有所降低,但HV30和KIC分別提高了15.4%和12.2%。

Abstract:選用了分散性能較差的4種商業(yè)氮化硅粉料，系統(tǒng)研究了表面水解及熱氧化處理對氮化硅粉料表面特性及分散性能的影響，并結(jié)合粉料的DRIFT光譜、離子電導(dǎo)率和可溶性離子濃度、以及表面氧含量的分析，總結(jié)了氮化硅粉料分散性能較差的限制性因素，提出1種普適性的制備氮化硅水基濃懸浮體的新方法。

Abstract:The high-temperature oxidation-resistant MoSi2 coating on the Nb substrate was prepared by slurry firing. The structure, composition and phase distribution of the coating and the relationship between these features and the oxidation resistance of the coating were investigated by SEM, EDS, and XRD. The results indicate that the interface between the coating and the substrate is metallurgical bond, and a transitional layer was formed by diffusion. The composite multi-layer structures improve the oxidation resistance properties of the coating. The method of slurry firing to prepare the high temperature MoSi2 coating on Nb was feasible. The SiO2 glass layer, which was formed on the surface of the coating by the self-oxidation of MoSi2, prevents oxygen from further diffusion. After a long time exposure in high temperature oxidizing environment, the porous microstructure was formed as a result of the diffusion of silicon in the coating. Due to further interdiffusion of the element, which takes place between the coating and the substrate, a large number of cavities which run through transversely are formed. The coating was broken through the interface between the body of the coating and the transitional layer.

Abstract:研究了添加0．5at％和1．0at％Zr對釤鐵合金微結(jié)構(gòu)和相組成的影響。添加和不添加Zr的Sm-Fe合金相比，發(fā)現(xiàn)添加1．0at％Zr可以基本消除鑄態(tài)組織中的α-Fe，并且能同時減少富釤相。多添加18at％Sm的Sm-Fe合金退火后，仍殘留少量的α-Fe，而添加1．0at％Zr的Sm-Fe-Zr合金退火后主相Sm2Fe17以及α-Fe的量沒有明顯的變化，因此有可能避免過長的均勻化退火過程。

Abstract:采用差示掃描量熱儀(DSC)研究了大塊金屬玻璃Pd40Ni10Cu30P20的結(jié)構(gòu)弛豫。結(jié)果表明金屬玻璃Pd40Ni10Cu30P20的結(jié)構(gòu)馳豫可分為2個階段：在400K～520K的溫度范圍，樣品發(fā)生的是低溫結(jié)構(gòu)弛豫，所伴隨的結(jié)構(gòu)變化是局域的和短程的，自由體積沒有發(fā)生明顯湮滅，所以樣品的密度變化不大。而在520K～玻璃轉(zhuǎn)變溫度Tg的溫度范圍，樣品發(fā)生的是高溫結(jié)構(gòu)弛豫，在這一過程中發(fā)生原子的中長程擴(kuò)散，部分自由體積通過樣品表面發(fā)生湮滅，因而導(dǎo)致樣品的密度顯著增加。實驗還表明，在Tg以下進(jìn)行預(yù)退火處理使得大塊金屬玻璃Pd40Ni10Cu30P20的玻璃轉(zhuǎn)變激活能明顯降低，但對后續(xù)的晶化過程的影響不大。

Abstract:Joining of Si3N4 / Si3N4 was carried out by using Cu68Ti20Ni12 fill metal. The results show that brazing temperature and holding time have an important influence on joining strength, and the highest strength value (289 MPa) was achieved at the brazing temperature of 1 373 K for 10 minutes. Microanalysis of the Si3N4/ Cu68Ti20Ni12 interfacial region showthat Ti and Ni concentrate towards Si3N4 and the enriched area of Ti is closer to Si3N4 ceramics, while Si diffuses towards braze layer and Cu element is concentrated in the center part of the joint; Interfacial region has two reaction layer. Reaction layer I is TiN while reaction layer II consists of TiN, Ti5Si4, Ti5Si3, Ni3Si and NiTi compounds .

Abstract:為了研究高能氪離子轟擊對純鋯水溶液中耐蝕性能的影響,純鋯樣品用LC-4型離子注入機(jī)在40℃溫度下進(jìn)行高能氪離子轟擊,注入劑量從1×1015ions/cm2到3×1016ions/cm2,注入能量為300keV。用X-射線光電子譜(XPS)分析注入表層元素價態(tài),俄歇電子譜(AES)測試氧化膜的深度分布,用透射電鏡(TEM)觀察轟擊樣品的形貌和結(jié)構(gòu)轉(zhuǎn)變,轟擊樣品在1N硫酸溶液中的耐蝕性能用動電位極化測量曲線表征。結(jié)果表明:高能氪離子轟擊樣品后其耐蝕性能大大降低,轟擊劑量越大,耐蝕性越差。最后討論了輻照腐蝕的機(jī)理。

Abstract:Amorphous MgNi hydrogen storage alloy was synthesized by mechanically alloying (MA). The electrochemistry property of the alloy prepared in different parameters was tested. The relationship between the mechanically alloying parameters, the microstructure of the alloy and the electrochemistry property was analyzed. The results show that the eclectrochemistry property of the alloy has a strong relationship with milling speed, ball/powder weight ration(R) and milling time.

Abstract:Carbonized La-Mo cathode applied in FU105 large powerful broadcast emission tube has been studied. Referred to carbonized Th-W cathode , the carbonizing techniques of La-Mo cathode was worked out. Exhausting and seasoning of carbonized La-Mo cathode for FU105 tube were carried out. Through the performance test of FU105 tube equipped with La-Mo cathode, the emission capacity and stabilization of carbonized La-Mo cathode were analyzed. The results show that the emission capacity of carbonized La-Mo cathode for FU105 tube has reached that of Th-W cathode, but its emission stabilization is not very good.

Abstract:摘要：利用真空甩帶機(jī)制備了Fe84Zr2．08Nb1．92Cu1B11金屬快淬薄帶。X射線衍射結(jié)果表明：薄帶經(jīng)570℃退火后析出納米化結(jié)構(gòu)bccα-Fe相，晶粒大小約為20nm～40nm，利用HP4294A阻抗分析儀測量了此納米晶薄帶中的巨磁阻抗效應(yīng)。結(jié)果顯示在低頻下阻抗隨外磁場單調(diào)減小，這主要是由于磁導(dǎo)率隨外磁場的變化導(dǎo)致的，高頻下阻抗隨外磁場變化出現(xiàn)1個峰值，這主要是由于橫向各向異性的原因。運(yùn)用計算機(jī)模擬了這一結(jié)果，發(fā)現(xiàn)磁導(dǎo)率隨外磁場的變化在外場與各向異性場的比值約為0．9處出現(xiàn)了峰值，巨磁阻抗效應(yīng)也在此位置出現(xiàn)峰值。并且隨著驅(qū)動電流頻率的增大峰值變大。

Abstract:Rare-earth composite oxide DyFeO3 was synthesized by adopting sol-gel method in citrate which belongs to the structure of peroviskite. Structural characteristics characterized by XRD and TEM indicate that this material is nanosized. The crystal structure shows a certain amount of lattice distortion due to the decrease of the grain size and the increase of the surface area. This material was made into gas sensors and measured its gas-sensing properties to ethanol, CO, H2, H2S etc. The results show that the sensors based on DyFeO3 have high sensitivity ,excellent selectivity and quick response&recovery behavior to H2S.

Abstract:Wear properties of TC4 alloy were systematically tested in air and vacuum (10-5Pa). The effects of load and sliding velocity on the wear rate of TC4 alloy were studied, and the microstructural analysis of the worn surface layer of TC4 alloy were carried out. In air, the microstructure of the surface layer presented slid band of dislocation at the lower sliding velocity, and micro-crack at the higher sliding velocity. In vacuum, the microstructure of the surface layer was refined to a gain size range of 50 nm~100 nm and comprised of high density of dislocations. Twins existed in the substructure of the surface layer at higher sliding velocities.

Abstract:利用放電等離子燒結(jié)技術(shù)研究了SHS的Ti3AlC2粉體的燒結(jié)過程。燒結(jié)溫度1450℃，壓力20MPa，真空燒結(jié)，保溫5min，可獲得相對密度達(dá)98．4％的致密燒結(jié)體，HV可達(dá)3．8GPa；燒結(jié)溫度為l500℃，則可獲得完全致密的燒結(jié)體，HV可達(dá)4．2GPa；燒結(jié)體的維氏硬度隨燒結(jié)溫度(1300℃～1500℃)的升高而增大；SEM分析表明，SPS技術(shù)燒結(jié)制備的Ti3AlC2陶瓷，片層大小隨燒結(jié)溫度的升高而增大。

Abstract:采用電化學(xué)測試技術(shù)和化學(xué)浸泡試驗對生物醫(yī)用TiNi基形狀記憶合金在生理鹽水中的腐蝕行為進(jìn)行了研究。結(jié)果表明，TiNi合金比TiNiCu合金陽極鈍化區(qū)拓寬，孔蝕電位正移，腐蝕率減小。通過EDX分析和SEM觀察發(fā)現(xiàn)，TiNi合金蝕孔內(nèi)存在富Ti貧Ni的Ti2Ni析出相，而TiNiCu合金存在Cu原子富集的CuNi相，從而驗證了這些析出相是萌生孔蝕的敏感位置。在生理鹽水中TiNiCu合金的耐蝕性比TiNi合金劣，其原因是TiNiCu合金有較多的殘余奧氏體及單斜和斜方的馬氏體結(jié)構(gòu)，存在不同晶體結(jié)構(gòu)區(qū)域，造成電化學(xué)性質(zhì)不均勻性，從而形成了腐蝕微電池，加速了活性溶解。

Abstract:在不通入活性氣體的條件下，采用三乙酰丙酮銥金屬有機(jī)物化學(xué)氣相沉積方法制備銥薄膜。結(jié)果表明：低于190℃長時間加熱使先驅(qū)體分子結(jié)構(gòu)改變，其C-H和C-O鍵斷裂活性升高，導(dǎo)致沉積薄膜中含有顯著數(shù)量的碳雜質(zhì)；高于220℃加熱先驅(qū)體和550℃沉積，可獲得致密連續(xù)、無雜質(zhì)碳并且呈亮銀白色的銥薄膜。

Abstract:During semiconductor manufacturing, the gold wire bonding is influenced by the native Al oxide film, and Au wire could not bond to Al bondpad.In this paper, SEM, EDS and AES are used to investigate the bondpads. It's found that the elements on the surface of Al bondpads after sawing are consistent with those of before sawing. So swilling techniques does not affect the wire bonding. The AES results show that there is 40% O element in Al bondpads even though at the depth of half of the Al bondpad height. Consequently, Al has already been oxidized by O. The Al oxide film which can prevent the bonding and the diffusion of O to Al causes the failure of wire bonding.

Abstract:Using two kinds of liquid medium and two dispersants, we investigated the dispersed characteristic of Ti(C,N)-based cermet hard phase powders TiC, TiN and WC. It is concluded that: for TiC, TiN, WC powder, aqua is more suitable than ethanol as a kind of liquid medium. For TiC and TiN, aether is an appropriate dispersant but for WC, polyglycolis considered.

Abstract:研究了真空熒光顯示屏陣列材料FeNi42Cr6合金在高溫濕氫氣氛中的氧化行為。其氧化過程為：首先形成Cr2O3，然后(Fe,Mn)Cr2O4氧化物形核、生長，形成完整氧化膜，成熟氧化膜由顆粒狀剛玉型氧化物Cr2O3和塊狀尖晶石型(Fe,Mn)Cr2O4氧化物組成。實驗同時表明，陣列板電阻率隨氧化膜厚度增加而增大，電阻率過高會導(dǎo)致與之焊接的Ni絲熔斷，氧化膜厚度應(yīng)控制在1μm～2μm。借助掃描電鏡、X射線衍射研究了氧化時間、氫氣流量、氫氣露點等工藝參數(shù)對陣列板氧化增重、氧化膜相結(jié)構(gòu)及、氧化膜表面形貌的影響。得出氧化溫度為950℃，時間40min～60min，氫氣露點(dp)35℃，流量8L／mm為最佳陣列材料氧化工藝。

Abstract:The effect of Nd2O3 on voltage and microstructure of ZnO varistor was studied, and a theoretical analysis of the mechanism of the effect was conducted. The results show that the voltage of ZnO varistor increases with the increase of Nd2O3 content in the range of 0 mol%~0.04 mol%. But when the content of Nd2O3 is more than 0.04 mol%, the voltage of ZnO varistor decreases with the increase of the content. The microstructure analysis indicates that the minimal additive exists in ZnO grain boundary in the form of a new compound and hinders the movement of grain boundary, which reduces the size of ZnO grain size and makes the grain more uniform, and as a result, Nd2O3 improve the voltage of the varistor greatly.

Abstract:采用熱壓燒結(jié)的方法制備了鎳鐵尖晶石基金屬陶瓷試樣,用于鋁電解的惰性陽極。實驗制得了相對密度大于98%的陽極試樣,并研究了試樣的導(dǎo)電性能和抗電解質(zhì)腐蝕性能。結(jié)果表明,所得的陽極試樣的電導(dǎo)率隨溫度的升高而增大,在900℃時電導(dǎo)率在40Ω-1·cm-1~60Ω-1·cm-1之間。在電解過程中,陽極電壓降平穩(wěn)(2.8V~3.2V),表明陽極的電阻在電解過程中沒有明顯變化,導(dǎo)電性能穩(wěn)定。用反電動勢法測量電解反應(yīng)的分解電壓為2.2V~2.5V,表明電解反應(yīng)為2Al2O3=4Al+3O2,電極呈現(xiàn)良好的惰性。電子顯微分析表明,試樣抗冰晶石-氧化鋁熔鹽腐蝕的性能良好,電解質(zhì)通過對Fe2O3的溶解來腐蝕陽極。

Abstract:Cu elements have been introduced into the Ti-6Al-4V substrate by using double glow plasma surface alloying technology to form burn-resistant alloyed layer on the surface. Composition and hardness in the alloyed surface layer gradually change in the depth direction of the substrate and its microstructure is substrate microstructure plus diffused Ti2Cu intermetallics. Abecedarian tests reveal that the copperized alloying layer has the function of burn-resistance.

Abstract:Photoluminescence(PL) of Gallium nitride (GaN) films grown by ammoniating Ga2O3/Al2O3 films deposited on silicon (111) by rf magnetron sputtering has been studied. The mechanism and the influence of growth condition on the photoluminescence is also studied. There are two emission peaks: a strong one at 347 nm, and a weak one at 412 nm. Increasing the ammoniating temperature and lengthening the ammoniating time, the intensities of both two peaks increase, but the in locations do not move. The peak at 347 nm is considered to be the blue-shift, which was caused by micro- size of GaN grains, of the band-edge emission peak of GaN. The emission peak at 412 nm is attributed to radiant combination from conduct band to the energy level of acceptor impurity.