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Abstract:In order to get an insight of the relations between the compositions, the microstructures and the mechanical properties, the experimental high-temperature structural intermetallic alloys comprised of L2_1-type(Co,Ni)_2AlTi and L1_2-type(Co,Ni)_3(Al,Ti) ordered phases in the system Co-Ni-Al-Ti were examined for various heat-treated microstructures by compression testing and fracture analysis. Some approaches to further improving the high-temperature strength and room-temperature ductility are discussed.

Abstract:The Al_2O_3 ceramics was bonded with Ti-6Al-4V using (Ag_ 72Cu_ 28)_ 97Ti_3 as filler metal under the conditions of 1 073 k~1 173 K and 18 ks. The interface structure and formation mechanism of joints were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS). It was found that the interface structure of diffusion-bonded joints is Al_2O_3/Cu_2Ti_4O/Cu_4Ti_3/Ag-Cu eutectic+rich Ag phase+Ti soild solution for bonding temperature below 1 123 K. For bonding temperature of 1 173 K, the interface structure is Al_2O_3/Cu_3TiO_5+CuAl_2O_4/Cu_4Ti_3/rich Ag phase. Strength of the Al_2O_3/(Ag_ 72Cu_ 28)_ 97Ti_3/Nb joint reaches 189 MPa for bonding temperature of 1 123 K and 18 ks. The lower bonding temperature, or the higher bonding temperature, the lower strength of joints.

Abstract:研究了金屬間化合物 Co Sb3作為鋰離子電池陽極材料在 1ML i PF6 /EC+ DMC( 1∶ 1)電解液中的電化學性能。具有 skutterudite結(jié)構(gòu)的 Co Sb3和不具有此種結(jié)構(gòu)的 Co Sb3最大可逆容量分別為 5 73 m Ah· g- 1 和 4 4 4 m Ah·g- 1 ,10個循環(huán)內(nèi)可逆容量分別保持在 4 0 0 m Ah· g- 1和 2 2 0 m Ah·g- 1以上 ,采用非原位 XRD方法研究二者嵌鋰機理 ,發(fā)現(xiàn) skutterudite結(jié)構(gòu)雖然不起儲鋰作用 ,但它破壞后形成的微觀結(jié)構(gòu)卻有利于循環(huán)過程。加入 10 % (質(zhì)量分數(shù) ,下同 )微碳球 MCMB后 Co Sb3電化學性能大大提高 ,最大可逆容量達 715 m Ah· g- 1 ,循環(huán) 2 0次后可逆容量保持在 5 0 0 m Ah· g- 1 以上。

Abstract:The rare earth oxide La_ 065Ca_ x MnO_3 with Ca vacancies were prepared, and the magnetic and electric transport behaviors were investigated. The experimental results show that with increasing Ca vacancies, the unit cell volume of La_ 065Ca _x MnO_3 increases, but the Curit temperature decreases and the ferromagnetic interaction is suppressed. The temperature of metal semiconductor transition, T _ tran, decreases, and the peak value of resistance increases with increasing Ca vacancies. The temperature dependence of the resistance above metal-semiconductor transition temperature is simulated based on the polaron-resistance model. The simulated results indicate that the increment of resistance for materials with Ca vacancies is associated with the decrement of decay length of local wave function. Meanwhile, the temperature dependence of resistance from 100 K to 300 K is calculated based on the Dionne model. The calculated data show that the polaron-trapping energy resulted from both the magnetic exchange interaction and the electron-phonon interaction enhance with increasing Ca vacancies, which reduces the active ability of the current carrier. The relationships among Ca content, amount of ions Mn 3+/Mn 4+ and oxygen vacancies in La_ 065Ca _x MnO_3 are also discussed in details.

Abstract:采用球磨濕混和旋轉(zhuǎn)合成相結(jié)合的新工藝制備了鋰離子電池正極材料 L i Ni0 .5Co0 .5O2 ,并對材料進行了粒度、化學成分以及電化學性能測試。球磨濕混工藝能將原料混合均勻 ,并能有效地使粒度細化。旋轉(zhuǎn)合成工藝能使混合料在均勻的溫度場中進行反應 ,并使反應產(chǎn)物粒度均勻和成分均勻。制備的 L i Ni0 .5Co0 .5O2 為單一的 α- Na Fe O2 層狀結(jié)構(gòu) ,粉末粒度分布范圍窄 ,平均粒徑約為 8μm～ 10μm。電化學性能測試結(jié)果表明 ,在 0 .2 m A/cm2 充放電流密度和 3 .0 V～ 4 .2 V電壓范圍內(nèi) ,首次充電容量為 173 m Ah/g,放電容量為 14 8m Ah/g。循環(huán)次數(shù)達 3 0次時 ,放電容量還有 12 9m Ah/g,循環(huán)穩(wěn)定性良好。球磨濕混和旋轉(zhuǎn)合成相結(jié)合的固相合成新工藝能制備出電化學性能良好的L i Ni0 .5Co0 .5O2 正極材料。

Abstract:研究了貯氫合金 Ml Ni3.6 5Co0 .75Mn0 .4 Al0 .2 的顆粒度及粒度分布均勻性對其電化學性能的影響。結(jié)果表明 :在2 0 0 m A/g(以貯氫合金的質(zhì)量計算 ,下同 )的充放電電流下 ,合金的粒度越小 ,首次放電容量越大 ,且活化速度越快 ,但其飽和容量 (活化后穩(wěn)定的放電容量 )隨粒度的增大而增加 ,且在某個最佳粒度時達到最大值 ,然后又逐漸降低 ;該合金的高倍率放電容量與其粒度之間也有相同的規(guī)律 ,只是在不同的放電電流下最佳粒度值不同 ,當放電電流小于 60 0 m A/g時 ,3 0μm～ 76μm合金粉的放電容量最大 ,當放電電流等于或大于 60 0 m A/g時 ,4 0μm～ 5 0μm合金粉的放電容量最大 ;放電電流越大 ,顆粒度對合金粉電化學性能的影響越顯著 ;在充放電電流為 3 0 0 m A/g時 ,除3 0μm以下的合金粉性能衰減較快外 ,其余各個粒度的合金粉的性能衰減速度幾乎相等 ;均勻的粒度分布有利于合金粉電化學性能的提高。

Abstract:The reaction rate of in situ formed TiC in molten aluminum has been studied. The calculated results show that decreasing the aluminum content in Ti-C-Al preform accelerates the reaction rate of TiC. Increasing the thickness of intermetallide layer and the size of C power reduces the reaction rate of TiC.

Abstract:The un-uniformed deformation TiC particle reinforced titanium matrix composite has been studied. The results show that the deformed frictional constraint appears between the particle and the matrix and resists the deformation of matrix and strengthens it.By using the theory of elastic-plastic mechanics,the deformed frictional constraint calculated is 0.6 times of the strength of TiC particle,when the stress gathering appears on the interface and the dislocation resource are formed at a certain crystalline plane,a series of dislocation rings release and the stress gathering on the interface is freed,in the meantime the density of dislocation in the matrix increases,the dislocations tangle each other to form celluloid substructure and thus strengthen the matrix.

Abstract:對于由L21型（Co,Ni)2AlTi和L1型（Co,Ni)3(Al,Ti)兩種有序相組成的Co-Ni-Al-Ti系新型金屬間化合物高溫結(jié)構(gòu)用合金，經(jīng)熱處理后獲得不同顯微組織的高溫壓縮和室溫斷裂等力學行為進行了分析研究，確立了合金成分、顯微組織和機械性能之間的關(guān)系，找到了進一步提高高溫強度和室溫塑性的途徑。

Abstract:The purification by plasma during sedimentation of particulates is studied in this paper. The analyzed and calculated data show that when sedimentation rate and time are suitable, the purity of particulates can be improved by two orders of magnitude. Some calculated data and improvements on purification are discussed in detail.

Abstract:In order to understand the behaviors of dissolution of TiN inclusions in liquid titanium alloys and evaluate the roles of alloying elements in the diffusion process, the diffusion and phase transformation near alpha region of TiN\Ti interface in C_pTi and Ti-6Al-4V have been studied. The artificially embedded TiN sponge particles dissolved into liquid alloys. The concentration profiles of nitrogen in the interfaces have been determined by microprobe for either as-cast or heat-treated samples. The experimental results show that the concentration profiles of nitrogen in phase transformation region show a steep change. The alloying elements Al and V retard the diffusion of nitrogen and dissolution of TiN particles.

Abstract:Thermal cycling conditions are among the most sever environmental conditions for composites and have a great effect on the micromechanical properties near interfaces.An AFM(atomic force microscope)-based nanoindentation method was employed to measure the nanohardness and the plastic deformation capacity near interfaces in graphite fiber reinforced aluminum alloy matrix composites(Gr/Al)after thermal cycling.With increasing of thermal cycles, the nanohardness values of both fibers and the matrix decrease and the plastic deformation capacity of the matrix increases.Both of the changes in the nanohardness and the plastic deformation capacity are dependent of the distance to the fiber-matrix interface.Changes in nanohardness can provide important information about residual strains because the local elastic or plastic residual strains have effects on the local hardness.

Abstract:在1．8ks，1073K－1173K條件下對Al2O3/(Ag72Cu28)97Ti3/Ti-6Al-4V進行了釬焊試驗。通過掃描電鏡、波譜、能譜、X射線衍射界面結(jié)構(gòu)進行了分析。小于1123K的界面結(jié)構(gòu)為Al2O3/Cu2Ti4O/Cu4Ti3/Ag-Cu共晶＋富Ag相＋Ti固溶體；1173K的界面結(jié)構(gòu)為Al2O3/Cu3TiO5 CuAl2O4/Cu4Ti3/富Ag相。采用拉剪試驗測試了接頭剪切強度。在1．8ks,1123K時剪切強度最高達到189MPa,大于或小于1123K接頭強度呈下降趨勢。

Abstract:研究了金屬間化合物CoSb3作為鋰離子電池陽極材料在1MLiPF6/EC+DMC(1∶1)電解液中的電化學性能.具有skutterudite結(jié)構(gòu)的CoSb3和不具有此種結(jié)構(gòu)的CoSb3最大可逆容量分別為573mAh*g-1和444mAh*g-1,10個循環(huán)內(nèi)可逆容量分別保持在400mAh*g-1和220mAh*g-1以上,采用非原位XRD方法研究二者嵌鋰機理,發(fā)現(xiàn)skutterudite結(jié)構(gòu)雖然不起儲鋰作用,但它破壞后形成的微觀結(jié)構(gòu)卻有利于循環(huán)過程.加入10%(質(zhì)量分數(shù),下同)微碳球MCMB后CoSb3電化學性能大大提高,最大可逆容量達715mAh*g-1,循環(huán)20次后可逆容量保持在500mAh*g-1以上.

Abstract:利用傳熱模型和物理模型計算了等離子旋轉(zhuǎn)電極法（簡稱PREP）和錘砧法（簡稱HAP）制備的TiAl合金的冷卻速度。計算結(jié)果顯示：以高純氬為冷卻介質(zhì)，PREP法制備的TiAl合金的冷卻速度為10^2K/s-10^4K/s；錘砧法的冷速為10^5K/s-10^6K/s。

Abstract:制備了Ca缺位型稀土金屬氧化物La0.65CaxMnO3，并對磁性及電輸運特性進行了研究。發(fā)現(xiàn)隨Ca缺位的增加，材料的晶胞體積增大，但居里溫度卻減小，鐵磁相互作用減弱。材料的金屬－半導體轉(zhuǎn)換峰值溫度Ttran隨Ca缺位程度的增加相應減小而電池峰值卻增大，作者用極化子電阻模擬合了金屬-半導體轉(zhuǎn)換峰溫度Ttran以上的電阻溫度依賴關(guān)系，發(fā)現(xiàn)Ca缺位材料的電阻的增大可能與局域波函數(shù)的衰減長度減小有關(guān)。還同時利用迪尼模型在100K－300K溫區(qū)內(nèi)，分析計算了材料電阻隨溫度的變化關(guān)系，發(fā)現(xiàn)磁交換能和電－聲相互作用能對極化陷阱能的貢獻有有Ca缺位時比無缺位時均有所增大。極化陷阱的增高減低了載流子的活動能力。同時還對Ca含量、Mn^ 3/Mn^ 4含量、氧缺位量存在的關(guān)系進行了討論。

Abstract:用納米壓入法測定了LY12鋁合金微弧氧化陶瓷膜的硬度H和彈性模量E分布，并探討了陶瓷氧化膜的生長機理。氧化膜的硬度和彈性模量分別為18GPa-32GPa,280GPa-390GPa?？拷ぃw界面的氧化膜硬度和彈性模量仍然相當高。H和E沿膜深度的分布都存在一個極大值，并同膜內(nèi)α-Al2O3含量變化是一致的。其形成原因在于微弧區(qū)熔融物在膜不同部位冷卻速率差異較大。

Abstract:The effects of additive Ni and Co on the microstructures and characteristics of CuCr25 alloys prepared by vacuum induction melting have been studied. The results show that both Ni and Co eliminate Cr segregation, and significantly improve the microstructures of CuCr25 alloys. The additive Ni and Co also increase the dielectric strength of the alloys, but slightly decrease electrical conductivity. As a result, the properties of vacuum induction melted CuCr25 alloys reach the specifications of conventional CuCr50 alloy.

Abstract:The CuCr25 alloys with high density and low oxygen content were prepared by means of vacuum induction melting. The effects of alloying elements (Ni-Al,W-Ni,W-Co) and microstructure on the physical properties and dielectric strength were investigated.The experimental results show that the chromium grains are refined when appropriate solidifying method and alloying elements are selected.On the other hand, the tungsten and cobalt serve the function of strengthening chromium phase.As a result, the dielectric strength increases notably.

Abstract:The alloy Cu-Ag with high strength and conductivity is studied in this paper. The tensile strength of 11 GPa and the conductivity of 80% international annealing copper standard (IACS) for the alloy have been obtained. The influences of deformation, heat treatment and alloying constituent on comprehensive properties of the alloy are discussed, and the strengthening mechanism is also analyzed.

Abstract:采用球磨濕混和旋轉(zhuǎn)合成相結(jié)合的新工藝制備了鋰離子電池正極材料LiNi0.5Co0.5O2，并對材料進行了粒度、化學成分以及電化學性能測試。球磨濕混工藝能將原料混合均勻，并能有效地使粒度細化。旋轉(zhuǎn)合成工藝能使混合料在均勻的溫度場中進行反應，并使反應產(chǎn)物粒度均勻和成分均勻。制備的LiNi0.5Co0.5O2為單一的α-NaFeO2層狀結(jié)構(gòu)，粉末粒度分布范圍窄，平均粒徑約為8μm-10μm。電化學性能測試結(jié)果表明，在0．2mA/cm^2充放電流密度和3．0V－4．2V電壓范圍內(nèi)，首次充電容量為173mAh/g，放電容量為148mAh/g。循環(huán)次數(shù)達30次時， 放電容量還有129mAh/g，循環(huán)穩(wěn)定性良好。球磨濕混和旋轉(zhuǎn)合成相結(jié)合的固相合成新工藝能制備出電化學性能良好的LiNi0.5Co0.5O2正極材料。

Abstract:利用透射電鏡觀察了Al-4Cr-4Zr-2Ti（原子百分比）合金的顯微組織，并測定了相應的顯微硬度。結(jié)果表明：快凝合金在400℃，4h時效達到峰值硬度，Hv達2420MPa，此時的析出相為Al13Cr2和與基體共格的亞穩(wěn)相Ll2-Al3Zr。合金經(jīng)400℃，96h時效后的顯微硬度與急冷態(tài)硬度和峰值硬度相比僅分別下降10％和14％。而500℃，4h時效后，由于Ll2-Al3Zr轉(zhuǎn)變?yōu)镈O23－Al3Zr并且析出相粗化，導致合金硬度急劇下降。

Abstract:研究了貯氫合金MlNi3.65Co0.75Mn0.4Al0.2的顆粒濃度及粒度分布均勻性對其電化學性能的影響。結(jié)果表明：在200mA/g（以貯氫合金的質(zhì)量計算，下同）的充放電電流下，合金的粒度越小，首次放電容量越大，且活化速度越快，但其飽和容量（活化后穩(wěn)定的放電容量）隨粒度的增大而增加，且在某個最佳粒度時達到最大值，然后又逐漸降低；該合金的高倍率放電容量與其粒度之間也有相同的規(guī)律，只是在不同的放電電流下最佳粒度值不同，當放電電流小于600mA/g時，30μm-76μm合金粉的放電容量最大，當放電電流等于或大于600mA/g時，40μm-50μm合金粉的放電容量最大；放電電流越大，顆粒度對合金粉電化學性能的影響越顯著；在放電電流為300mA/g時，除30μm以下的合金粉性能衰減較快外，其余各個粒度的合金粉的性能衰減速度幾乎相等；均勻的粒度分布有利于合金粉電化學性能的提高。

Abstract:采用SHS還原法以CaWO4,Mg粉為原料制備鎢粉。研究了CaWO4-Mg合成過程中的物理化學變化，壓坯壓力、稀釋劑和浸出對燃燒過程和產(chǎn)物的影響。隨著壓坯壓力的增加，燃燒產(chǎn)物的空隙率和鎢粉顆粒的粒度呈遞減趨勢。添加稀釋劑（鎢粉），鎢粉顆粒的粒度有所增大。通過進一步堿浸可提高鎢粉的純度。最終產(chǎn)物的成分光譜分析和粒度分析結(jié)果表明：可得到平均粒徑為0．87μm，比表面積1．09m^2/g，純度≥99．0％的鎢粉。

Abstract:采用電子束物理氣相沉積（EB－PVD）方法在DZ22合金基體上沉積制得了在NiCoCrA1Y粘結(jié)層和YSZ（Yt-tria Stabilized Zirconia)陶瓷頂層組成的雙層結(jié)構(gòu)的熱障涂層。研究了NiCoCrA1Y粘結(jié)層表面的噴丸強化處理對熱障涂層的抗氧化性能的影響，利用MTS測試了經(jīng)等溫氧化不同時間后的熱障涂層內(nèi)部的結(jié)合強度，并采用SEM和XRD觀察和分析了涂層的界面結(jié)合以及相組成。結(jié)果表明，等溫氧化后熱障涂層內(nèi)部的結(jié)合強度急劇降低，在位伸和剪切應力作用下，涂層沿著TGO（Thermally Grown Oxide）層內(nèi)部斷裂失效，強度為0．3MPa的表面噴丸處理能顯著提高熱障涂層的抗氧化性能和涂層內(nèi)部TGO層的結(jié)合強度。

Abstract:采用鈦材研制了可返轉(zhuǎn)的嬰幼兒胸骨、肋骨牽開器。此器件由齒條板、固定臂、活動臂、撥輪、搖柄把、帶弧度可返轉(zhuǎn)的檔板組成。經(jīng)100家醫(yī)院在心臟直視手術(shù)室間隔缺損、房間隔缺損、法樂氏四聯(lián)癥、部分心內(nèi)膜墊缺損、動脈導管未閉結(jié)扎等先天性心臟病手術(shù)中臨床應用獲得滿意效果。