靶电流对TiAIN/TiN复合膜组织及硬度的影响

采用多弧离子镀技术在 40Cr 基体上制备 TiAlN/TiN 复合膜层,通过金相显微镜、扫描电镜和显微硬度仪研究靶电流对膜层表面形貌、沉积率及硬度的影响.结果表明:靶材电流对膜层组织和硬度有显著影响,电流越高膜层表面越不平整,显微硬度随靶材电流的升高先上升后降低.靶电流越高,膜层中 Ti、Al 原子的含量就越高.     

靶电流对TiAlN/TiN复合膜组织及硬度的影响

采用多弧离子镀技术在40Cr基体上制备TiAlN/TiN复合膜层,通过金相显微镜、扫描电镜和显微硬度仪研究靶电流对膜层表面形貌、沉积率及硬度的影响。结果表明:靶材电流对膜层组织和硬度有显著影响,电流越高膜层表面越不平整,显微硬度随靶材电流的升高先上升后降低。靶电流越高,膜层中Ti、Al原子的含量就越高。     

电弧离子镀沉积TiAlN膜层的微观特性

采用高纯铝、钛双靶源在TC11基材上沉积制备了TiAlN膜层,并分析研究了膜层微观特性.结果表明:沉积的TiAlN膜层厚2～3 μm,膜层结构致密;可明显地观察到膜基界面处Ti、Al和N三种元素呈梯度分布,存在元素扩散,使膜层与基体间形成冶金结合;膜层沉积过程中钛靶电流对相结构有明显的影响,而基体偏压对相结构无明显影响.     

15CrMnMoVA钢磁控溅射镀铝防护层耐腐蚀性能

采用磁控溅射技术,在15CrMnMoVA钢上镀覆一层纯铝防腐蚀薄膜。利用盐雾机、电化学测量仪、扫描电镜和能谱仪对比基体和铝涂层样品的耐腐蚀性能,同时分析偏压、靶电流、沉积时间等因素对涂层耐腐蚀性能的影响。结果表明,铝膜厚度为8.2μm的样品,铝膜层晶粒均匀,大小为1～2μm、膜/基界面平整、结合良好,其中基体与膜层界面处致密的过渡层对提高样品的耐腐蚀性作用显著;在中性盐雾气氛中,516h出现红锈;Al膜沉积时间为1h的样品,其自腐蚀电流比基体低2个数量级,达到icorr=-6.53×10-8 A,能有效提高基体的耐腐蚀性,膜层在中性盐雾腐蚀气氛下失效方式为逐层失效;薄膜沉积过程中,提高负偏压、靶电流和镀膜时间,均能提高膜层的质量。     

基于X射线反射研究溅射工艺对CrAlN/TiAlN周期膜界面结构的影响

为研究X射线反射技术在纳米多层膜界面微结构表征中的应用,采用反应磁控溅射技术在单晶硅基片上制备CrAlN/TiAlN纳米周期膜,利用X射线反射技术系统研究溅射工艺参数对CrAlN/TiAlN纳米周期膜界面微结构的影响规律。结果表明:增加铝靶功率可提高膜层的溅射速率和降低膜层的界面粗糙度,然而较高的铝靶功率会使膜层界面出现严重的弥散;较大和较小的负偏压都不利于形成完整的周期膜调制结构和光滑的界面;提高Ti/Cr靶电流可有效改善周期膜的调制界面结构,但太大的靶电流会导致膜层间扩散加重,形成弥散界面。N2流量与Ar流量对膜层界面粗糙度具有相反的影响作用。试验得到的优化工艺参数为:铝靶功率80W,溅射负偏压-200 V,Ti/Cr靶电流0.2A,N2流量30cm~3/min,Ar流量10cm~3/min。     

电弧离子镀CrN薄膜的制备及性能研究

以气压、弧电流和偏压为影响因素设计正交试验,采用电弧离子镀技术在6Cr13Mo马氏体不锈钢表面沉积Cr N薄膜。利用扫描电镜、显微硬度计、划痕仪对Cr N薄膜的厚度、硬度、结合力进行检测,研究薄膜性能并优化其制备工艺。结果表明:靶电流对薄膜厚度及结合力影响最大,随着电流升高,膜层厚度急剧增大,而结合力逐渐降低;对薄膜硬度影响最大的为负偏压,随着偏压升高,膜层硬度先升高后降低。综合考虑Cr N薄膜的表面质量、硬度、结合力,得到最佳制备工艺为气压1.4 Pa、靶电流100 A、偏压-100 V。     

不同Ti靶电流对Ti掺杂类石墨碳膜的结构和性能的影响(英文)

利用磁控溅射的方法成功制备Ti掺杂类石墨碳(Ti-GLC)膜。采用拉曼光谱、X射线光电子谱(XPS)、扫描电子显微镜(SEM)、原子力显微镜(AFM)、纳米压痕仪和球盘式摩擦机分别表征不同Ti靶电流下制备的Ti-GLC膜的成分、结构和性能。随着Ti靶电流的增加,薄膜中sp2键的比率和Ti含量增加,同时薄膜的硬度和内应力也增大,但较高的Ti靶电流将会促使薄膜产生鳞片状结构从而使其变疏松。较少的Ti掺入量可以降低GLC膜的干摩擦因数,纯GLC膜在水润滑条件下的摩擦因数最低。在较低Ti靶电流下制备的Ti-GLC膜在干摩擦及水润滑条件下均具有较高的抗磨性能。     

QTi2.5/Cu同基合金离子镀

采用同基合金电弧离子镀方法,在紫铜基体上制备了Cu-Ti合金薄膜,研究了弧电流和靶.基距离对膜层质量、沉积速率的影响.结果表明,镀层沉积速率随着弧电流的增加而增大,随靶-基距离的增大而下降;镀层近表面为层片状组织,镀层表面有颗粒存在,显示电弧源后期喷射的是Cu-Ti合金液滴;近界面处,组织细密,晶粒较小.镀层由沉积层和过渡层构成,Ti含量由表至里逐渐降低,过渡层的存在有利于提高膜-基结合力.镀层显微硬度呈梯度分布,表面显微硬度约为铜基材的3倍.     

中频对靶磁控溅射合成TiN/Ti多层膜

利用新型中频对靶磁控溅射技术合成了一系列TiN／Ti多层膜．考察了不同Ti间隔层对多层膜硬度和结合力的影响,分析了膜表面大颗粒和坑的形成机理;利用正交实验法和方差分析探讨了靶电流、气体压力和基体偏压对薄膜表面缺陷密度的影响,对工艺参数进行了优化．结果表明,靶电流对缺陷密度的影响最大,气体压力次之,基体偏压对缺陷密度影响最小;当靶电流I=20A、气体压力ρ（Ar＋N2）=0．31Pa、基体偏压Vbias=-16m--300V和Ti间隔层厚度x-=0．12μm时,制备出硬度HV0．2N=2250、膜基间结合力（临界载荷）Lc=48N和表面缺陷密度ρs=58mm^-2的高质量TiN／Ti多层膜．     

靶电流对非平衡磁控溅射制备无氢碳膜结构与性能的影响

利用非平衡磁控溅射(UBMS)技术在硅基片上制备了无氢碳膜,并采用Raman光谱、X射线衍射、傅立叶变换光谱等手段对不同靶电流下沉积的薄膜的微观结构、沉积速率、粗糙度、表面接触角及红外透过率进行了研究.试验结果表明:随着靶电流的增大,薄膜的沉积速率增大,薄膜中sp3键含量增加,薄膜表面接触角增大,红外透过率增大;而薄膜的粗糙度随靶电流增加而减小.靶电流是影响非平衡磁控溅射制备无氢碳膜结构与性能的1个主要因素.     

X-ray diffraction study of Ba0.985Na0.015Ti0.985Nb0.015O3, Ba0.6Na0.4Ti0.6Nb0.4O3 and Ba0.3Na0.7Ti0.3Nb0.7O3 compositions

The Ba_0.985Na_0.015Ti_0.985Nb_0.015O₃, Ba_0.6Na_0.4Ti_0.6Nb_0.4O₃ and Ba_0.3Na_0.7Ti_0.3Nb_0.7O₃ compositions of the (1 − x) BaTiO₃–xNaNbO₃ (BTNNx) system have been studied by X-ray diffraction and by measurements of dielectric properties. The specimens with composition BTNN (x = 0.015, 0.40 and 0.70) have been refined by the JANA program from X-ray powder diffraction data. Ceramic samples with composition (1 − x) BaTiO₃ + xNaNbO₃ (where x = 0.015, 0.40 and 0.70) were prepared by calcinations from appropriate mixture of BaCO₃, TiO₂, Na₂CO₃ and Nb₂O₅. The calcined powder was sintered at temperature range 1200–1400 °C. As the composition x increased from 0.015 (and 0.70), the ferroelectric ceramics (x = 0.015, FE) with tetragonal phase changed to the ferroelectric relaxors (RFE, x = 0.40). RFE ceramics showed a peculiar diffuse phase transition and dielectric relaxation at the low temperature (down to 180 K) due to a frustration between RFE and FE state. These ceramics present the classical ferroelectric character when 0 ≤ x < 0.075 and 0.55 < x ≤ 1 and relaxor character when 0.075 ≤ x ≤ 0.55.     

Magnetic, electrical and plastic properties of Fe76Nb2Si13B9, Fe75Ag1Nb2Si13B9 and Fe75Cu1Nb2Si13B9 amorphous alloys

Influence of 1 h annealing in vacuum on magnetic, electrical and plastic properties of Fe₇₆Nb₂Si₁₃B₉, Fe₇₅Ag₁Nb₂Si₁₃B₉ and Fe₇₅Cu₁Nb₂Si₁₃B₉ melt spun ribbons were carefully investigated. It was shown that in all cases soft magnetic properties can be significantly enhanced by applying 1-h annealing at characteristic temperatures T_op. This optimization annealing causes that permeability increases more than 15-times and magnetic losses (tangent of loss angle) achieves a minimum in relation to the as quenched state. Using structural examinations (X-ray and HRTEM) it was shown that for the Fe₇₅Cu₁Nb₂Si₁₃B₉ alloy the optimized microstructure corresponds to a nanocrystalline αFe(Si) phase whereas in other alloys to a relaxed amorphous phase free of iron nanograins. As a consequence of this fact the Fe₇₆Nb₂Si₁₃B₉ and Fe₇₅Ag₁Nb₂Si₁₃B₉ alloys show higher plasticity in comparison to the nanocrystalline Fe₇₅Cu₁Nb₂Si₁₃B₉ alloy. Temperatures of the first stage of crystallization, and related diffusion parameters were determined using measurements of resistivity versus temperature with different heating rates.     

Fe2+-Ni2+-NH3-NH4+-C2O42-H2O体系的沉淀配合平衡热力学

针对草酸盐配位共沉淀热分解还原法制备超细铁镍合金粉过程中Fe2+-Ni2+-NH3-NH4+-C2O42--H2O体系的溶液平衡建立热力学分析模型,并根据模型进行相关计算,揭示反应体系中各物质随pH值、氨及草酸浓度的变化关系。结果表明:溶液中的Fe主要以[Fe(C2O4)n]2 2n络合物形式存在,而铁氨络合物含量很低。当氨含量较低时,溶液中的Ni主要以[Ni(C2O4)n]2 2n存在;氨含量较高时,在酸性条件下,溶液中的Ni主要以[Ni(C2O4)n]2 2n存在,在碱性条件下,则主要以[Ni(NH3)n]2+存在。低pH值下,Ni的沉淀率较Fe的高,而高pH值下,Ni的沉淀率则较Fe的低。     

Al2O3-Sm2O3-CeO2电解质的性能（英文）

采用溶胶-凝胶法和低温燃烧技术制备Ce1-xSmxO2（x=0,0.1,0.2,0.3）和掺杂Sm和（2%-8%）Al2O3的二氧化铈;研究其合成、结构、致密化、导电性和热膨胀等性能,并利用XRD研究其结构和相组成。结果表明,于1300°C烧结球团,获得致密的陶瓷,于1250°C在Ce0.8Sm0.2O0.2中加入2%和4%的Al2O3以促进烧结。利用扫描电子显微镜观察烧结后球团的表面形貌,使用双探针交流阻抗谱研究总离子电导率。     

Synthesis and electrochemical properties of LiNi0.4Mn1.5Cr0.1O4 and Li4Ti5O12

Spinel compound LiNi_0.4Mn_1.5Cr_0.1O₄ (LNMCO) and Li₄Ti₅O₁₂ (LTO) were synthesized by the sol-gel method and the solid-state method, respectively. The particle sizes of the products LiNi_0.4Mn_1.5Cr_0.1O₄ and Li₄Ti₅O₁₂ were 0.5 to 2 um and 0.5 to 0.8 um, respectively. All samples exhibited excellent electrochemical properties. A LiNi_0.4Mn_1.5Cr_0.1O₄/Li₄Ti₅O₁₂ (LNMCO/LTO) cell was fabricated and was demonstrated to exhibit good electrochemical properties at the high current rate of 1 C. When the specific capacity was determined based on the mass of the LNMCO cathode, the LNMCO/LTO cell delivered 125 mAh g⁻¹ at 1 C and 77 mAh g⁻¹ at 5 C. The capacity retentions after 30 cycles were 94.4 % and 83.1 %, respectively.     

Sinterability and dielectric properties of Ba0.55Sr0.4Ca0.05TiO3-CaTiSiO5-Mg2TiO4 composite ceramics

The composite ceramics of Ba_0.55Sr_0.4Ca_0.05TiO₃-CaTiSiO₅-Mg₂TiO₄ (BSCT-CTS-MT) were prepared by the conventional solid-state route. The sintering performance, phase structures, morphologies, and dielectric properties of the composite ceramics were investigated. The BSCT-CTS-MT ceramics were sintered at 1100 °C and possessed dense microstructure. The dielectric constant was tailored from 1196 to 141 as the amount of Mg₂TiO₄ increased from 0 to 50 wt%. The dielectric constant and dielectric loss of 40 wt% Ba_0.55Sr_0.4Ca_0.05TiO₃-10 wt% CaTiSiO₅-50 wt% Mg₂TiO₄ was 141 and 0.0020, respectively, and the tunability was 8.64% under a DC electric field of 8.0 kV/cm. The Curie peaks were broadened and depressed after the addition of CaTiSiO₅. The optimistic dielectric properties made it a promising candidate for the application of tunable capacitors and phase shifters.     

Thermodynamics and phase diagrams in the binary systems Na2O-SiO2, Na2O-GeO2, Na2O-B2O3, Li2O-B2O3, CaO-B2O3, SrO-B2O3, and BaO-B2O3

We applied our model to the enthalpy of mixing data of the binary systems Na₂O-SiO₂, Na₂O-GeO₂, Na₂O-B₂O₃, Li₂O-B₂O₃, CaO-B₂O₃, SrO-B₂O₃, and BaO-B₂O₃. The most stable composition in the liquid, that is where the enthalpy of mixing is most negative, is with a metal-oxygen ratio of 4 to 3, for monovalent metals (Na and Li) and 3 to 4 for divalent metals (Ba and Ca) in liquid silicates or borates. The same applies to the CaO-SiO₂, CaO-Al₂O₃, PbO-B₂O₃, PbO-SiO₂, ZnO-B₂O₃, and ZnO-SiO₂ systems. The oxygen to metal ratio, its constant value in various types of systems, reflects and describes the structure of the liquid. Using the analyzed enthalpies of mixing data and the available phase diagrams, we calculated the enthalpies of formation of the various binary compounds. The results are in excellent agreement with data in the literature that were obtained from direct solid-solid calorimetry.     

Phase transition and piezoelectric properties of K0.48Na0.52NbO3-LiTa0.5Nb0.5O3-NaNbO3 lead-free ceramics

Plate-like NaNbO₃ (NN) particles were used as the raw material to fabricate (1 − x)[0.93 K_0.48Na_0.52Nb O₃-0.07Li(Ta_0.5Nb_0.5)O₃]-xNaNbO₃ lead-free piezoelectric ceramics using a conventional ceramic process. The effects of NN on the crystal structure and piezoelectric properties of the ceramics were investigated. The results of X-ray diffraction suggest that the perovskite phase coexists with the K₃Li₂Nb₅O₁₅ phase, and the tilting of the oxygen octahedron is probably responsible for the evolution of the tungsten-bronze-typed K₃Li₂Nb₅O₁₅ phase. The Curie temperature (T_C) is shifted to lower temperature with increasing NN content. (1 − x)[0.93 K_0.48Na_0.52NbO₃-0.07Li(Ta_0.5Nb_0.5)O₃]-xNaNbO₃ ceramics show obvious dielectric relaxor characteristics for x > 0.03, and the relaxor behavior of ceramics is strengthened by increasing NN content. Both the electromechanical coupling factor (k_p) and the piezoelectric constant (d₃₃) decrease with increasing amounts of NN. 0.01-0.03 mol of plate-like NaNbO₃ in 0.93 K_0.48Na_0.52NbO₃-0.07Li(Ta_0.5Nb_0.5)O₃ gives the optimum content for preparing textured ceramics by the RTGG method.