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Abstract:Recent developments in Ceramic Injection Molding (CIM) techniques are reviewed. The influence of the ceramic powder and the formulation of the organic binder (especially the surfactant) on the ceramic feedstock, and the green and sintered parts are discussed in detail. Also, the influence of the mixing sequence, the injection parameters, the debinding methods, and the corresponding debinding rate on the fluidity of feedstock, and the properties of the green and sintered parts are described here.

Abstract:以水／環(huán)己烷／曲拉通-100／正己醇四元油包水微乳體系中的微乳液滴為納米微反應(yīng)器，通過分別增溶在微反應(yīng)器中的氧氯化鋯和沉淀劑(氨水)發(fā)生反應(yīng)，可以制備出粒徑分布均勻、球形度較好的納米級超細(xì)氧化鋯粉體。實(shí)驗(yàn)中采用粒度分析儀，XRD，SEM，TEM，比表面儀等對獲得的粉體進(jìn)行了表征，利用高溫綜合熱分析儀分析了粉體的致密化行為，發(fā)現(xiàn)在燒結(jié)致密化過程中，無定型態(tài)的粉體于475℃左右結(jié)晶成為四方相的氧化鋯，在1080℃～1280℃范圍內(nèi)完成致密化收縮。干壓成型的坯體在1400℃，2h下燒結(jié)相對密度達(dá)98％以上，燒結(jié)體晶相為100％的四方相。

Abstract:通過計(jì)算機(jī)對Pd基大塊金屬玻璃的過冷液相區(qū)寬度△Tx的表達(dá)式進(jìn)行回歸處理分析，得到Pd基大塊金屬玻璃過冷液相區(qū)△Tx與反映合金混合熱變化的3個鍵參數(shù)(電負(fù)性差△X、原子尺寸差的百分?jǐn)?shù)δ和電子濃度n)之間存在如下關(guān)系：△Tx=29．36909 3602．45898(△x)^2 9992．76758δ^2-3．95897n^2/3，相關(guān)系數(shù)為97．2％。△Tx隨多元合金的電負(fù)性差和原子尺寸差的百分?jǐn)?shù)的增加而增加，而隨電子濃度的增加而略有降低。

Abstract:用磁控濺射法將NiTi薄膜沉積在純Cu箔片上，在800℃分別固溶30min，45min，60min和120min：采用X射線傅氏線形分析法計(jì)算各固溶時間的位錯密度及位錯分布參量。隨固溶時間的增加，平均位錯密度不斷下降；亞晶粒尺寸D逐漸增加；平均位錯分布參量基本不變。由位錯密度及位錯分布參量計(jì)算得到NiTi薄膜材料的顯微硬度值，隨固溶時間的增加，顯微硬度計(jì)算值明顯低于測量值。

Abstract:根據(jù)1種新的Sol—Gel工藝設(shè)計(jì)思路，提出了在SiO2-CaO-MgO-P2O5多元體系中制備均勻凝膠的方法，并采用RAMAN，XRD和SEM對制得的凝膠物性進(jìn)行了分析。結(jié)果表明：利用該方法可以成功地制備出均勻的生物凝膠。生物凝膠分子網(wǎng)絡(luò)呈群聚態(tài)，包括架狀、層狀、鏈環(huán)狀、二聚體及單體，以架狀為主。隨熱處理溫度升高，生物凝膠的晶化程度增加。生物凝膠干燥試樣中有大量微裂紋和孔洞，并含有殘余OH基團(tuán)。試樣的這些特性可增加其在溶液中與水和小分子蛋白質(zhì)鍵合的能力。

Abstract:通過對混合元素法Ti-Fe合金燒結(jié)過程中的膨脹／收縮行為、淬火態(tài)和燒結(jié)態(tài)顯微組織的分析，研究了添加鐵對混合元素法Ti—Fe合金的燒結(jié)行為和組織演化的影響。結(jié)果表明：鐵元素對鈦粉末的燒結(jié)行為的影響可分為2個階段：(1)鐵元素的擴(kuò)散均勻化；(2)單相的β-Ti(Fe)的燒結(jié)致密化。在升溫速率為5K／min和鐵含量為5w／％的情況下，鐵元素在Ti-Fe系的第1共晶點(diǎn)(1085℃)之前就完全固溶到鈦基體中，瞬時液相并沒有出現(xiàn)。添加鐵元素促進(jìn)了Ti—Fe合金的燒結(jié)致密化。隨著鐵含量的提高，原始β晶粒平均尺寸及片狀α晶團(tuán)(Colony)的平均尺寸略有增加，α片的平均厚度急劇下降。鐵的高擴(kuò)散速率和鐵的β相穩(wěn)定效果是導(dǎo)致這些結(jié)果的主要原因。

Abstract:The electromagnetic force of electromagnetic casting induced in cylindrical molten metal was analyzed by mathematical method and experiment research. It can be concluded that where is the electromagnetic force impose on and what is the direction of the force, and the electromagnetic force was concerned not only with the magnetic flux density but also with the grads of the magnetic flux density. Furthermore, it can be summarized that the nonconservative component of the force was brought by the asymmetry of the distribution of the electromagnetic field. Some experiments are taken to research the influence of the parameters (inductor current, inductor shape etc.) on the distribution of the electromagnetic fields.

Abstract:在 SPF-430H 濺射系統(tǒng)上采用不加偏壓的射頻磁控濺射法制備了 TbCo 非晶垂直磁化膜, 并就 Cr 底層對 TbCo 非晶垂直磁化膜磁性能的影響進(jìn)行了研究。結(jié)果表明,Cr 底層的存在能夠增強(qiáng) TbCo 非晶垂直磁化膜的磁各向異性,并使得其矯頑力增加。分別采用 VTBH-1 型高感度振動樣品磁強(qiáng)計(jì)和 MTL-1 磁轉(zhuǎn)矩系統(tǒng)測量了 TbCo薄膜的磁滯回線和磁轉(zhuǎn)矩曲線。結(jié)果發(fā)現(xiàn),厚度為 120 nm,并帶有 180 nm 厚度 Cr 底層的 Tb31C69 薄膜的矯頑力和磁各向異性能分別高達(dá) 51.2×104 A/m 和 0.457 J/cm3;沒有帶 Cr 底層的同樣厚度的 Tb31C69 薄膜的矯頑力和磁各向異性能分別只有 35.2×104 A/m 和 0.324 J/cm3。Hitachi X-650 型掃描電鏡的觀測結(jié)果表明,帶有 Cr 底層的TbCo 薄膜具有柱狀結(jié)構(gòu),這一柱狀結(jié)構(gòu)導(dǎo)致了磁各向異性能的增強(qiáng)以及矯頑力的提高。

Abstract:The crystal loops of Gallium nitride (GaN) were deposited on silicon (111) substrate by using hot-wall chemical vapor deposition and thermal treatment. Scanning electron microscopy (SEM), selected area electron diffraction (SAED), x-ray diffraction (XRD), photoluminescence (PL) and Fourier Transform Infrared transmission (FTIR) Spectroscopy were employed to analyze the surface morphology, structure and optical properties of GaN layer. SEM image shows five half-loops attached to a crystal string side by side in the uniform films. XRD, SAED patterns reveal that the formed loops are polycrystalline hexagonal gallium nitride. FTIR pattern shows the main composition of the film is GaN and it contains trifle carbon contamination. New feature is found in PL pattern of the crystal loops, which is different from the bulk GaN films.

Abstract:利用溶膠-凝膠自燃燒高溫合成法制備了稀土La摻雜鋇鐵氧體BaLa0.3Fe11.7O19納米粉末.用X射線衍射儀、振動樣品磁強(qiáng)計(jì)和透射電鏡對不同溶膠組成下合成的粉末的結(jié)構(gòu)、磁學(xué)性能、粒度及形貌進(jìn)行了研究.試驗(yàn)表明用氨水調(diào)節(jié)溶液起始pH值以及加入適量的檸檬酸和乙二醇是合成結(jié)構(gòu)純凈、性能優(yōu)異的BaLa0.3Fe11.7O19納米粉末的2個關(guān)鍵步驟.在溶液起始pH值呈弱酸性(7.0左右)、檸檬酸/硝酸鹽=3、煅燒溫度為850℃,保溫1 h的條件下,利用溶膠-凝膠自燃燒高溫合成法可以制備出粒徑為36nm的磁鉛石結(jié)構(gòu)的BaLa0.3Fe11.7O19粉末,其磁學(xué)性能優(yōu)異,比飽和磁化強(qiáng)度可達(dá)65.54 A·m2/kg,矯頑力可達(dá)433 kA/m.

Abstract:通過X射線衍射(XRD)、金相顯微鏡、掃描電鏡(SEM)、能譜分析(EDS)及壓痕技術(shù)研究了Er對Mo5Si3基合金(鉬硅質(zhì)量比5：1)室溫組織與性能的影響。研究結(jié)果表明：Er的添加導(dǎo)致了三元化合物相Mo3Er2Si4的形成：合金的組織形貌隨Er含量不同有所差異，且隨Er含量增加，組織中MoSi2相逐漸減少，三元化合物的含量則逐漸增加：過渡族元素Er在MoSi2中不固溶，在Mo5Si3中的溶解度也極?。篍r含量為1wt％時得到略高的室溫硬度值。Er難以明顯改善室溫?cái)嗔秧g性。

Abstract:采用雙層輝光離子滲碳技術(shù)在本底真空度為 5×10-3Pa 的高真空下,用 99.999%的高純氬氣進(jìn)行無氫滲碳。在整個工藝過程中,沒有涉及到氫元素,實(shí)現(xiàn)了無氫滲碳。試樣材質(zhì)為 TA1 工業(yè)純鈦,用透射電鏡(TEM)觀察滲層結(jié)構(gòu);X 射線衍射(XRD)測定滲層的相組成;用 M200 耐磨試驗(yàn)機(jī)測定滲碳試樣的耐磨性能;滲碳試樣的磨痕表面狀態(tài)用 TR240型粗糙度儀測定。滲碳層厚度大于 100 μm。表面層生成的是 TiC,基體仍為 α-Ti。近表面滲層維氏硬度為 6 000 MPa,表面的硬度遠(yuǎn)大于此值。摩擦系數(shù) 0.11。純鈦經(jīng)過無氫滲碳后,與未經(jīng)過處理的純鈦相比磨損量僅為純鈦試樣的1/1 592.5。研究得出:鈦材經(jīng)過雙輝等離子無氫滲碳后,不僅提高了表面的硬度,同時降低了摩擦系數(shù),因而使耐磨性能得到了大幅度的提高。

Abstract:通過力學(xué)性能、電學(xué)性能測量和金相、電鏡觀察對Cu-Al2O3彌散強(qiáng)化銅合金的冷加工及退火后性能和組織的變化進(jìn)行了系統(tǒng)研究。結(jié)果表明：擠壓態(tài)合金隨冷拉拔變形量增大，σb和σ0.2逐漸升高，δ逐漸下降，電導(dǎo)率則變化甚微。合金經(jīng)92％的變形后，σb，σ0.2,δ和電導(dǎo)率分別為490MPa，485MPa，10％和91．4％IACS，其在400℃～1000℃溫度范圍退火后性能有不同程度的回復(fù)。不同變形量的合金樣品900℃ 1h退火后性能均回復(fù)至擠壓態(tài)水平，且未見再結(jié)晶現(xiàn)象。冷拉拔有利于粉末顆粒間進(jìn)一步冶金化結(jié)合。

Abstract:采用 PHI-650 型掃描俄歇電子能譜(SAM)研究金屬鈾在超高真空原位斷裂后斷面在不同氧氣暴露量和溫度下的氧化規(guī)律和雜質(zhì)元素在表面的擴(kuò)散行為。實(shí)驗(yàn)中采用在主真空室內(nèi)的裝置在超高真空中打斷鈾樣品,然后在 1×10-5 Pa的壓力下充入暴露量為 5 L、20 L、70 L、170 L 和 270 L 的高純氧氣進(jìn)行氧化實(shí)驗(yàn)并獲取 U,O,S 和 C 的俄歇電子譜。實(shí)驗(yàn)結(jié)果表明:在 5 L 和 20 L 的氧氣暴露量下表面形成 UO2 和金屬 U 的混合物,在大于 70 L 情況下只形成 UO2。 在1×10-7 Pa 的真空中將 UO2 加熱到 100℃,150℃,200℃和 300℃并進(jìn)行 SAM 分析,結(jié)果顯示:隨溫度的升高,尤其是在 300℃時元素 S 向表面擴(kuò)散,形成明顯的富集,且表面氧和鈾的原子濃度比明顯下降。

Abstract:AlN-15BN composite ceramics were produced via pressureless sintering process with BN powders bought from market and AlN powders synthesized by carbothermal reduction method as starting materials, and Y2O3 as sintering aids. The effects of sintering temperature on the phases, density, microstructure of AlN-BN ceramics were studied. The results showed that Y2O3 reacted with Al2O3 presenting on the surfaces of AlN particles and formed liquid phases to promote the densification. The density, thermal conductivity and hardness increased with the increas of sintering temperature, and the plate-like BN crystalline could form a card-house structure which hampers the densification of composite ceramics. AlN-BN composite ceramics with thermal conductivity 104.2 W?m-1?K-1, relative density 86.4% and HRA hardness 562 MPa were produced after being sintering at 1 850 for 3 h.

Abstract:The effect of surface oxide layer on the activation behavior of TiMn1.25Cr0.25 alloy is discussed through different exposure time to air prior to activation. The activation results imply that activation of TiMn1.25Cr0.25 alloy becomes more difficult with the time of exposure to air prolonging. The auger Electron Spectroscopy (AES) results present that an about 6 nm~10 nm thick oxide layer is formed on the surface of TiMn1.25Cr0.25 alloy, which is a important factor of effect the activation behavior of this alloy. The scanning electron microcopy (SEM) result show that the activation process of TiMn1.25Cr0.25 alloy is closely related with alloy grain fragmentation.

Abstract:Cu film deposited on ZrN and TaN diffusion barriers is annealed in vacuum and H2, N2 mixed gas respectively. SEM morphology, XRD and resistivity are employed to characterize the thermal stability of the multilayer. The experiment demonstrates that for the multilayer deposited on the same kind of diffusion barrier, the thermal stability of multilayer annealed in H2, N2 mixed gas is superior to that annealed in vacuum. While for the multilayer annealed in vacuum, the thermal stability of the multilayer deposited on ZrN diffusion barrier is better than that deposited on TaN diffusion barrier. The investigation shows that the evaluation of the thermal stability of the multilayer should take not only some intrinsic factors of the multilayer itself, for instance diffusion barriers, but also the annealing ambient into account.

Abstract:The microstructure of Co-Cr-W alloy plasma surfacing has been investigated using metallurgical phase, X-ray diffraction, SEM and TEM. The results indicated that the alloy layer was composed of Co base solid solution with the preferred direction at (200) crystal plane and (Cr, Fe)7(C, B)3. The TEM research showed that there was a lot of stacking fault ribbons lying in Co-base solid solution. The result also showed that (Cr, Fe)7(C, B)3 was hexagonal lattice with lamellar and flake twin.

Abstract:The Cu thin films on (111) of Si substrate were prepared by the co-sputtering equipment of ion beam enhance deposition, using the nano-indentation experiments, the elastic moduli and hardnesses of Cu films at different annealing temperature were obtained. The yield strength of Cu film was calculated by FEM model based on the nano-indentation experiments. It is found that yield strength of Cu film is much higher than that of bulk of Cu. And the annealing temperature affects the yield strength of film greatly. From XRD spectrum, it is analyzed that the decrease of yield strength of Cu film results from the change of crystal size and crystal plane.

Abstract:OH radical is one of the reactive oxygen species, and is very oxidative. It can injure the body. Rare earth Ce3+ in cerium nitrate can change over between Ce3+ and Ce4+, and can react with OH radicals. In this study OH radicals were produced by nano-TiO2 which can produce OH radicals after irradiated by ultraviolet radiation. Cerium nitrate was mixed with nano-TiO2, then DMPO was employed to catch OH radicals. The result of electron spin resonance(ESR)shows that the quantity of OH radicals produced by nano-TiO2 mixed with cerium nitrate is much less than that without cerium nitrate, thus approves cerium nitrate can effectively rid OH radicals.

Abstract:Using X-ray diffraction and the cross correlation method to determine the peak of diffraction plane (114), the residual stress distribution along the surface layer in the titanium alloy TC18 caused by shot peening was measured during step-by-step electrolytic dissolution. Relaxation of the compressive residual stress caused by shot peening at high temperatures and during cyclic stress was investigated. The characteristics of residual compressive stress field have also been analyzed; it was determined that the maximum compressive residual stress is a intrinsic parameter that is not affected by shot peening. From the above experimental results some practical laws have been derived, which offers a basis for the shot peening processing decision as it applies to the TC18 titanium alloy.

Abstract:The preparation method and arc erosion characteristics of the AgNi and AgSnO2 contacts materials which was fabricated by high-energy ball milling, hot pressing and sintering were studed. The powder morphology and microstructure of contact were analyzed by X-ray Diffraction (XRD), Scan Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). The results shows that the grain size of composite powder has been fined, that the particle size of second phase was about 40 nm after high energy ball milling and the particles are dispersed in the Ag matrix in inlaying and welding, in witch the second phase aggregatin in the matrix and deposition on the grain bourdary that was caused by orthodox method has been abated. After hot pressing and annealing, there was not obviously growth of second phase and the particle size was about 50 nm. It was also found that the Ag film distributed on the grain boundary was retained in both contacts, which was propitious to the improvement of conductance capability. Compared with the commercial contacts, there was not obviously melting pool and splash of fused mass on the nanocomposite contact surface, which indicated that the arc on the contact surface was dispersed and the material was possessed of less are erosion in the arcing process.

Abstract:以CePO4與Ce-ZrO2等比例混合的含粘結(jié)劑的料漿為連接材料，在坯體狀態(tài)下無壓連接了可加工CePO4／Ce—ZrO2陶瓷與Ce-ZrO22陶瓷。對影響接點(diǎn)性能的工藝條件進(jìn)行了討論，材料的燒成溫度和保溫時間會明顯影響連接效果，對25CePO4．Ce—ZrO2／Ce-ZrO2體系，在1450℃保溫120min左右時，可實(shí)現(xiàn)最佳的連接效果。接點(diǎn)SEM分析表明，25CePO4/Ce—ZrO2和Ce-ZrO2連接體系中可形成結(jié)構(gòu)均勻的擴(kuò)散接點(diǎn)區(qū)域，其微觀結(jié)構(gòu)與母體材料的基本一致，接點(diǎn)的平均抗彎強(qiáng)度也與母體材料相似。用坯體無壓連接法適合復(fù)雜形狀本體或異體組合陶瓷構(gòu)件，其工藝流程簡單，加工成本低廉。

Abstract:The character of Sn-Zn-Ga solder alloy, including a series of properties tests, such as melting point, hardness, shear strength and solderability was studied. The results show that Ga element can decrease the melting point of solder alloys, but increase the melting range, and also reduce the hardness and shear strength of solder alloys. In addition, Ga element can enhance the wetting ability of solder alloys. The best composition of Sn-Zn-Ga lead-free solder alloy was obtained.

Abstract:GaN films on Si substrates were obtained by hot-wall chemical vapor deposition and the growth condition during the process was investigated. The structure, surface morphology and the optical properties were characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM) and photoluminescence (PL). It indicated that hexagonal wurtzite GaN films were obtained on Si substrates. Preliminary results suggest that H2 as carrier gas play an important role at the same temperature in the growth of GaN films.

Abstract:系統(tǒng)研究了 NiTi 形狀記憶合金表面電化學(xué)方法制備 HA 生物涂層過程中工藝參數(shù)對涂層相組成及其結(jié)構(gòu)和形貌的影響,得出了最佳沉積規(guī)范,在該規(guī)范下沉積的涂層均由 CaHPO4·2H2O 組成,經(jīng)堿處理后完全轉(zhuǎn)變?yōu)?HA。所制備的 HA 涂層均勻致密,一定條件下涂層形貌由傳統(tǒng)的針狀轉(zhuǎn)變?yōu)槠瑢訝睢３醪教接懥?HA 涂層形貌發(fā)生轉(zhuǎn)變的機(jī)理。