Al3Ni2的一个超结构相

Ａｌ３Ｎｉ２的一个超结构相郝朝斌王蓉（北京科技大学材料物理系，１０００８３）Ａｌ３Ｎｉ２（τ３）相是一种空位有序相，实验上已观察到由十次准晶向Ａｌ３Ｎｉ２的五重畴结构的转变［１］，然而，Ａｌ３Ｎｉ２结构并不满足准晶近似相的大单胞特征［２］。已有工作［...     

纳米粉添加剂对Al2O3陶瓷烧结性能及微结构的影响

用纳米ＺｒＯ３作为烧结助剂加入Ａｌ２Ｏ３陶瓷中,研究其对Ａｌ２Ｏ３陶瓷烧结性能及显微结构的影响。结果表明,纳米ＺｒＯ２的加入可以提高Ａｌ２Ｏ３陶瓷的烧结活性,降低烧结温度,当纳米ＺｒＯ２的加入量达到９ｖｏｌ％时,Ａｌ２Ｏ３陶瓷在１６００℃以下就可烧结致密,此外,纳米ＺｒＯ２的加入,对Ａｌ２Ｏ３陶瓷的显微结构也产生影响。在纳米ＺｒＯ２加入量较少时,ＺｒＯ２粒子以“晶内型”和晶界型两种形式存在;而当ＺｒＯ２加入量达到９ｖｏｌ％时,其主要位于四个Ａｌ２Ｏ３晶粒相交的晶界上,阻碍了Ａｌ２Ｏ３晶粒的异常长大,从而获得细晶结构的Ａｌ２Ｏ３陶瓷材料。     

Ni_3Al（B）－Cr基合金再结晶过程的电镜研究

Ｎｉ３Ａｌ（Ｂ）－Ｃｒ基合金再结晶过程的电镜研究林一坚１，２吴杏芳１柯俊１Ｒ．Ｗ．Ｃａｈｎ（１北京科技大学材料物理系，北京１０００８３）（２上海钢铁研究所应用基础部，上海２００９４０）（英国剑桥大学）Ｎｉ３Ａｌ（Ｂ）－Ｃｒ基合金是含共格γ相的γ′和γ...     

铝合金激光熔覆Ni-WC涂层的组织及耐磨性

采用５ｋＷＣＯ２激光器，对ＺＡ１１１合金表面的Ｎｉ－ＷＣ等离子涂层进行了熔覆处理。利用ＳＥＭ和Ｘ射线衍射分析了激光层中的组织分布，并对激光处理后的试样进行了耐磨性实验。实验结果表明，激光熔层中的组织以镍铝基的金属间化合物Ａｌ３Ｎｉ，Ａｌ３Ｎｉ２，ＡｌＮｉ和Ｎｉ３Ａｌ为主；ＷＣ颗粒基本在熔区中熔化，在冷却过程中以弥散碳化物形式析出。这些组织的存在使得激光熔层具有很高的硬度，其润滑磨损耐磨性为未经激光处理喷涂层的１．７５倍和Ａｌ－Ｓｉ合金基体的２．８３倍。     

新型陶瓷刀具材料JX－2－I界面结构的实验研究

利用ＴＥＭ和电子衍射图谱分析，研究了新型陶瓷刀具材料ＪＸ－２－Ｉ的界面微观结构。ＴＥＭ分析表明，ＪＸ－２－Ｉ刀具材料的界面结合状态较好，Ａｌ＿２Ｏ＿３／ＳｉＣｗ界面上形成了具有较高强度的“钢筋混凝土”结构，在Ａｌ＿２Ｏ＿３／ＳｉＣｗ和Ａｌ＿２Ｏ＿３／ＳｉＣｐ界面上没有剧烈的化学反应发生；通过ＴＥＭ和电子衍射图分析，发现在Ａｌ＿２Ｏ＿３的晶粒边界上有尖晶石（ＭｇＡｌ＿２Ｏ＿４）生成，这有利于控制Ａｌ＿２Ｏ＿３晶粒的长大，提高复合材料的强度。     

Al2O3／SiC纳米复合材料微结构及强韧化机理

Ａｌ２Ｏ３／ＳｉＣ纳米复合材料微结构及强韧化机理＊李理侯耀永（青岛化工学院高技术陶瓷研究室，青岛２６６０４２）（清华大学新型陶瓷与精细工艺国家重点实验室）微米级陶瓷固体为基，纳米级陶瓷粒子为弥散相的纳米颗粒复合材料具有优异的力学性能，在断裂强度和断裂...     

Al_2O_3颗粒对Al-Zn合金激光快凝组织的影响

通过比较Ａｌ－Ｚｎ合金和Ａｌ_２Ｏ_（３ｐ）／Ａｌ－Ｚｎ复合材料的激光重熔组织。分析Ａｌ_２Ｏ_３颗粒对Ａｌ－Ｚｎ合金激光快凝组织的影响规律。实验结果表明,Ａｌ_２Ｏ_３颗粒可以显著细化激光熔区的晶粒。基于凝固界面与颗粒交互作用的理论分析,给出了晶粒细化的临界条件。     

新型复相陶瓷刀具材料JX—2—I的界面结构及其对材料性能的影响

本文利用ＴＥＭ研究了新型复相陶瓷刀具材料ＪＸ－２－Ｉ的界面结构，结果表明，在ＪＸ－２－Ｉ中Ａｌ２Ｏ３／ＳｉＣｗ（氧化铝／碳化硅晶须）界面和Ａｌ２Ｏ３／ＳｉＣｐ（碳化硅颗粒）界面结合良好，形成了具有较高强度的微观结构，发现在ＳｉＣｗ，ＳｉＣｐ和Ａｌ２Ｏ３晶粒上均有位错产生，在ＳｉＣｐ和Ａｌ２Ｏ３上有孪晶产生，分析表明，位错和孪晶的产生均吸收大量的断裂能，提高材料的断裂韧性，改善ＪＸ－２－Ｉ材料的整体     

γ-TiAl金属间化合物合金激光熔敷高温自润滑耐磨复合材料涂层

以 Ｎｉ８ＯＣｒ２０、Ｃｒ_３Ｃ_２、Ａｒ、ＣａＦ_２／ＢａＦ_２四元混合粉末为原材料,利用激光熔敷技术在ｒ－ＴｉＡｌ金属间化合物合金Ｔｉ－４８Ａｌ－２Ｃｒ－２Ｎｂ表面上制得了以ｒ一ＮｉＣｒ为基体、以初生Ｍ_７Ｃ_３及Ｍ_（２３）Ｃ_６为耐磨相、以弥散分布颗粒Ａｇ、ＣａＦ_２或ＣａＡｇＦ_４为自润滑相的高温自润滑耐磨复合材料涂层,涂层显微硬度大大提高且与基体呈冶金结合。     

新型复相陶瓷刀具材料JX－2－Ⅰ的界面结构及其对材料性能的影响

本文利用ＴＥＭ研究了新型复相陶瓷刀具材料Ｊｘ－２－Ⅰ的界面结构，结果表明，在Ｊｘ－２－Ⅰ中Ａｌ＿２Ｏ＿３／ＳｉＣｗ（氧化铝／碳化硅晶须）界面和Ａｌ＿２Ｏ＿３／ＳｉＣｐ（碳化硅颗粒）界面结合良好，形成了具有较高强度的微观结构；发现在ＳｉＣｗ、ＳｉＣｐ和Ａｌ＿２Ｏ＿３晶粒上均有位错产生，在ＳｉＣｐ和Ａｌ＿２Ｏ＿３上有孪晶产生；分析表明，位错和孪晶的产生均吸收大量的断裂能，提高材料的断裂韧性，改善ＪＸ－２－Ⅰ材料的整体性能。     

H13钢表面激光选区熔覆Ni-Al金属间化合物涂层的组织与性能

通过控制Ni 基自熔性合金粉末中Al 的含量,在H13 热作模具钢表面分别原位制备了Ni3Al和NiAl 金属间化合物复合熔覆涂层。借助光学显微镜和X 射线衍射仪对不同熔覆涂层的化学组成和物相结构进行了分析。结果表明,四种不同Al 含量的熔覆层均显现出平整致密、无明显缺陷的宏观特征。随着Al 含量的增加,熔覆层显微形貌呈现出底部枝晶区域增加及枝晶逐渐粗化,甚至出现胞状晶的现象。熔覆层在未加入Al 时,其主要物相为Ni3Fe 及（Ni, Cr）固溶体。随着Al 含量的增加,主要物相则由最初的Ni3Al 金属间化合物、（Ni, Cr）固溶体到Ni3Al、NiAl 金属间化合物和（Fe,Cr）固溶体,再到最终Al 含量达到13.9%时的NiAl 金属间化合物和（Fe,Cr）固溶体。同时,Al 含量的提高使得涂层中杂质相减少。熔覆层摩擦系数均低于基体,最高显微硬度为基体的3.5 倍,耐磨性较基体提高了5.8 倍。     

利用EBSD技术对690合金不同类型晶界处碳化物形貌的研究

利用扫描电子显微镜（SEM）、电子背散射衍射（EBSD）技术和取向成像显微（OIM）软件研究了Ni基690合金中不同类型晶界处碳化物的形貌。不同类型晶界处析出碳化物的形貌有很大区别,在孪晶的非共格界面（Σ3i）附近,棒状碳化物向两侧晶粒内部生长,而类似的棒状碳化物只向Σ9晶界一侧的晶粒内部生长。Σ3i与Σ9晶界附近的棒状碳化物的生长方向与基体晶粒的{111}面平行。晶界上析出的碳化物尺寸随着Σ值的升高而明显增大。在相同的腐蚀条件下,晶间腐蚀的痕迹随着Σ值的升高变得严重。     

Schottky Barrier Height Modulation of Nickel–Dysprosium-Alloy Germanosilicide Contacts for Strained P-FinFETs

This letter reports on the fabrication and hole Schottky barrier $(Phi_{ rm B}^{rm p})$ modulation of a novel nickel (Ni)–dysprosium (Dy)-alloy germanosilicide (NiDySiGe) on silicon–germanium (SiGe). Aluminum (Al) implant is utilized to lower the $Phi_{rm B}^{rm p}$ of NiDySiGe from $sim$0.5 to $sim$ 0.12 eV, with a correspondingly increasing Al dose in the range of $ hbox{0}$–$hbox{2}timeshbox{10}^{15} hbox{atoms}/ hbox{cm}^{2}$. When integrated as the contact silicide in p-FinFETs (with SiGe source/drain), NiDySiGe with an Al implant dose of $hbox{2}timeshbox{10}^{14} hbox{atoms}/ hbox{cm}^{2}$ leads to 32% enhancement in $I_{rm DSAT}$ over p-FinFETs with conventional NiSiGe contacts. Ni–Dy-alloy silicide is a promising single silicide solution for series-resistance reduction in CMOS FinFETs.      

K418合金激光熔覆Ni-Cr-Ti-Al涂层的组织研究

采用机械球磨法获得混合均匀的Ni-Cr-Ti-Al熔覆材料;并利用CO2激光器在K418镍基高温合金表面制备了不同化学成分的Ni-Cr-Ti-Al涂层;采用光学显微镜(OM)、扫描电子显微镜(SEM)及X射线衍射仪(XRD)等手段探讨了不同成分涂层与基体合金的结合情况。分析比较了Ni,Ti和Al含量对熔覆涂层的组织特征的影响。结果表明,在熔覆过程中,Ti,Al合金元素与Ni相互作用将形成Ni2TiAl,Ni3(Al,Ti),Ni3Ti和NiAl金属间化合物相;Ni-Cr-Ti-Al熔覆涂层以Ni3(Al,Ti)相形成的枝晶组织为主,Ni2TiAl,Ni3Ti及NiAl相分布在Ni3(Al,Ti)枝晶间;其中,Ni66.11Cr7.35Ti14.39Al12.15熔覆涂层形成了TiAl合金与K418合金之间成分和性能的良好过渡,为实现TiAl合金/K418合金异种合金间的扩散连接提供了良好的组织基础。     

Effect of the Phase Shift in a Periodic Anode on the Emission Spectra of Top-Emitting Organic Light-Emitting Diodes

Top-emitting organic light-emitting diodes with an Al–Ag cathode and $hbox{Al}+(hbox{Ni}hbox{–}hbox{Au})_{n}$ anode were proposed and fabricated. The multiple layered anode results in a phase shift at the metal interfaces. It was also found that theoretically calculated peak wavelengths of the intensity spectra agree well with those experimentally measured from the fabricated devices. These results also indicate that the phase shift effect in periodic anode is important for microcavity devices.      

Sonochemical Activation of Al/Ni Hydrogenation Catalyst

This paper proposes a sonochemical approach to the nanostructuring of Al/Ni catalyst with high content of accessible Ni centers and a high reusability. The surface and bulk composition as well as pore size distribution of this catalyst are controlled synergistically by adjusting the ultrasound intensity in aqueous solution. Sonochemical activation of Al/Ni alloy leads to formation of mesoporous Al/Ni metallic based frameworks with surface area up to 125 m² g^?1, and regular distribution of nickel active center in the porous matrix. One of the opportunities of porous Al/Ni catalyst is that due to a time‐resolved controllable formation of protective oxide layer it can be stored and handled under air in comparison to traditional Raney catalysts which need inert conditions. The Al/Ni catalyst is characterized by scanning electron microscopy (SEM), electron diffraction spectroscopy (EDS), X‐ray photoelectron spectroscopy (XPS), confocal scanning fluorescence microscopy (CSFM), solid‐state NMR experiments, and powder X‐ray diffraction analysis (PXRD). The catalytic activity was investigated for the hydrogenation of acetophenone.     

7B04铝合金板沿厚度方向显微组织、织构及力学性能的研究

本文通过扫描电镜(SEM)及常规力学性能试验对7B04铝合金板沿厚度方向的显微组织、织构及力学性能进行了详细的研究,结果显示:样品芯部及表层晶粒都沿轧制方向拉长,芯部基本未发生再结晶,小角度晶界的含量随着离芯部距离的增加而减少,再结晶程度逐渐加强;未回溶相S(Al2CuMg)、Al7Cu2Fe、Al18Cr2Mg3在芯...     

A thermodynamic and kinetic description of PCBM phase segregation and aggregation in P3HT:PCBM blends

The kinetics and thermodynamics of PCBM phase segregation and aggregation in P3HT:PCBM blends has been studied. We develop a thermodynamic model for PCBM phase segregation in P3HT:PCBM blends which explains the formation of nanoscale crystallites which subsequently diffuse and coalesce into larger PCBM aggregates. We show that the formation of nanoscale crystallites during the film making process prevents spinodal decomposition of the P3HT:PCBM blends even at PCBM weight fractions above the spinodal decomposition boundary for the system. Finally, we demonstrate that the observed aggregate morphology can be understood in terms of a kinetic model based on the diffusional flux lines of PCBM crystallite which, in turn, govern the evolution of the macroscopic growth front.     

Comparative Study of the Low-Frequency-Noise Behaviors in a-IGZO Thin-Film Transistors With $hbox{Al}_{2}hbox{O}_{3}$ and $hbox{Al}_{2}hbox{O}_{3}/hbox{SiN}_{x}$ Gate Dielectrics

A comparative study is made of the low-frequency noise (LFN) in amorphous indium–gallium–zinc oxide (a-IGZO) thin-film transistors (TFTs) with $hbox{Al}_{2}hbox{O}_{3}$ and $hbox{Al}_{2}hbox{O}_{3}/hbox{SiN}_{x}$ gate dielectrics. The LFN is proportional to $hbox{1}/f^{gamma}$, with $gamma sim hbox{1}$ for both devices, but the normalized noise for the $hbox{Al}_{2}hbox{O}_{3}/hbox{SiN}_{x}$ device is two to three orders of magnitude lower than that for the $hbox{Al}_{2} hbox{O}_{3}$ device. The mobility fluctuation is the dominant LFN mechanism in both devices, but the noise from the source/drain contacts becomes comparable to the intrinsic channel noise as the gate overdrive voltage increases in $hbox{Al}_{2}hbox{O}_{3}/hbox{SiN}_{x}$ devices. The $hbox{SiN}_{x}$ interfacial layer is considered to be very effective in reducing LFN by suppressing the remote phonon scattering from the $hbox{Al}_{2}hbox{O}_{3}$ dielectric. Hooge's parameter is extracted to $sim !!hbox{6.0} times hbox{10}^{-3}$ in $hbox{Al}_{2}hbox{O}_{3}/hbox{SiN}_{x}$ devices.      

激光合成Ni85Al15掺杂钨精矿粉合金组织及性能研究

为了提高复合材料的硬度、强度及耐磨性能,采用高能束激光诱发自蔓延原位自生反应合成金属陶瓷颗粒增强复合材料的方法,在过共晶Ni85Al15粉末中添加质量分数为0.01,0.015和0.02的钨精矿粉并压制成坯激光烧结后,得到了烧结合金的X射线衍射和扫描电子显微硬度、磨损测试结果。未添加钨精矿粉时,烧结合金的合成产物主要有NiAl,Ni3Al和Al2O3等相;添加钨精矿粉后,烧结合金产物增加了Ni4W和WO3相;当钨精矿粉的质量分数为0.01时,烧结合金相对密度最高为5.84g/cm3,其孔隙率最低为0.13%,合金硬度最高为325.2HK,磨损率最低为0.27mg/mm2。结果表明,钨精矿粉的加入,能够增加材料的硬度及其耐磨性能,当其质量分数达到0.01时,材料的硬度和材料的耐磨性能最优。