调质结构对Ti-TiN-Zr-ZrN多层膜力学性能影响

采用真空阴极电弧离子镀技术,在TC11钛合金和单晶Si片表面分别沉积不同调制周期、不同R_Ti/TiN:R_Zr/ZrN调制比和不同厚度的Ti-TiN-Zr-ZrN多层膜。用扫描电镜、X射线衍射仪、划痕仪、显微硬度计和应力测试仪分析测试了多层膜的截面形貌、厚度、结合力、硬度和残余应力;重点研究了调制周期、调制比和膜层厚度等调制结构的改变对多层膜残余应力和相关性能的影响。结果表明：增加调制周期,则残余应力降低,结合力和硬度均增大;降低RTi/TiN:RZr/ZrN调制比,则残余应力增大,结合力下降,硬度增加;增大多层膜厚度,则残余应力略有上升,结合力和硬度都提高,当膜层厚度达到7.54μm后,硬度稳定在30Gpa左右。     

镍改性层增强铜基底沉积金刚石膜的形核(英文)

在铜基底溅射约100nm厚的镍改性层,然后置入纳米金刚石悬浮液中超声震荡加载籽晶,随后在热丝化学气相沉积设备中制备出晶体颗粒接近热力学平衡形态的高质量金刚石膜,其中sp2碳相含量低于5.56%。分别采用激光拉曼光谱、扫描电镜与X射线衍射对金刚石膜的形核与生长进行研究。实验结果表明:在溅射有镍改性层的铜基底上,金刚石的形核密度比在无改性层的铜基底上的形核密度高10倍。镍改性层的增强机制主要来源于两个方面:镍改性层的纳米级粗糙表面增强金刚石籽晶颗粒的吸附;镍改性层的强催化效应加速铜基底上金刚石形核生长所需的石墨过渡层的形成,从而促进金刚石的快速形核。     

Influence of nanometer lanthanum fluoride on friction and wear behaviors of bonded molybdenum disulfide solid lubricating films

Influence of nanometer lanthanum fluoride (nano-LaF₃) on the friction and wear behavior of bonded molybdenum disulfide (MoS₂) solid lubricating film was investigated using an oscillating friction-wear tester under dry friction condition. The worn surface of the lubricating film and the transfer film formed on the surface of the counterpart ball were observed by SEM. The microstructure of the lubricating film filled with nano-LaF₃ and the distribution of F and La in the lubricating film were investigated with transmission electron microscopy (TEM) and field emission scanning electron microscope (FESEM) equipped with an energy dispersive X-ray spectrometer, respectively. It was found that nano-LaF₃ as a filler contributes to improve the wear-resistance property of the lubricating film. The lubricating film modified with nano-LaF₃ filler exhibits better wear-resistance property than that of the lubricating film without nano-LaF₃ filler at a relatively lower load (less than 250 N) and within a wide oscillatory frequency range between 5 and 35 Hz. However, the incorporation of nano-LaF₃ filler results in small increase of friction coefficient of the lubricating film. Transmission electron microscopy (TEM) and elementally X-ray map results of the lubricating film modified with nano-LaF₃ filler indicate that partial LaF₃ nanoparticles distribute around the MoS₂ particles, while other LaF₃ nanoparticles disperse in the binder. The SEM morphology of the frictional surface shows that the filler of nano-LaF₃ is able to enhance the compactness of the frictional surface, and results in an improvement of the wear-resistance property of the MoS₂ lubricating film.     

退火温度对ZnTe薄膜结构和性能的影响

采用脉冲激光沉积法(PLD)在玻璃衬底上通过室温溅射和原位退火制备了ZnTe薄膜。通过X射线衍射(XRD)、原子力显微镜(AFM)、紫外-可见分光光度计和荧光分光光度计等研究了退火温度对薄膜结构和性能的影响。结果表明:薄膜具有明显的<110>择优生长特征。随着退火温度的升高,薄膜结晶质量逐渐提高,晶粒长大,透过率增加;但过高的退火温度降低了晶体的结晶质量和透过率。当退火温度为280℃时,ZnTe薄膜具有最好的结晶质量,平均透过率达到90%左右。     

Preparation of flee-standing diamond films for high frequency SAW devices

Free-standing diamond films were prepared by hot filament chemical vapor deposition （HFCVD） method under different conditions. Inter-digital transducers （IDTs） were formed on the nucleation sides of free-standing diamond films by photolithography technique. Then piezoelectric ZnO films were deposited by radio-frequency（RF） reactive magnetron sputtering to obtain the ZnO/diamond film structures. Surface morphologies of the nucleation sides and the IDTs were characterized by means of scanning electron microscopy （SEM）, atomic force microscope （AFM） and optical microscopy. The results indicate that the surfaces of nucleation sides are very smooth and the IDTs are of high quality without discontinuity and short circuit phenomenon. Raman spectra show the sharp diamond feature peak at about 1 334 cmI and the small amount of non-diamond carbon in the nucleation side. X-ray diffraction （XRD） patterns of the structure of ZnO/diamond films show a strong diffraction peak of ZnO （002）, which indicates that as-sputtered ZnO films are highly c-axis oriented.     

Effect of annealing temperature on structure and electrochemical properties of LiCoO2 cathode thin films

LiCoO2 thin films, which can be used as a cathode material in microbatteries, were deposited using radio frequency (r.f.) magnetron sputtering system from a LiCoO2 target and in an O2+Ar atmosphere.The films were characterized by various methods such as XRD, SEM and AFM.The LiCoO2 films were annealed in air at 300, 500, 700 and 800 ℃ respectively.The effect of the annealing temperature on the structure, the surface morphology and the electrochemical properties of the films were investigated.The LiCoO2 thin film deposited at room temperature is amorphous and has smaller grain size.With increasing of annealing temperature, the crystallinity of the films is promoted.When the annealing temperature increases to 700 ℃, the films have a perfect crystalline LiCoO2 phase.The LiCoO2 thin film without annealing has no discharge plateau and small discharge capacity (about 27 μAh·cm-2μm).The discharge capacity increases with the increasing of annealing temperature and reaches 47 μAh·cm-2μm for the film annealed with 700 ℃, which also shows the typical discharge plateau of 3.9 V.The cycle performance of LiCoO2 thin films of as grown and annealed at different temperatures were studied.In the case of the film without thermal treatment, the capacity fading is much faster than that of the film annealed at different temperature, showing about 40% capacity loss only after 25 cycles.However, in the case of the film annealed at 700 ℃, the capacity reaches to steady state gradually and maintained constantly with cycling.After 25 times cycling, the discharge capacity of the film annealed at 700 ℃ decreases to about 36.9 μAh·cm-2·μm, only 0.8% capacity loss per cycle.     

大型卧式主轴改进设计一例

在设计机床主轴结构时,要根据机床的用途不同,工作条件不同,作具体分析,解决关键问题.对于卧式布置的大型主轴,结构设计上要在保证主轴达到精度要求的条件下,着重解决因自重而引起的安装、调整、维修不便的问题,若重视不够,将使机床不能正常工作.     

Effect of the molecular structure of some quinones on their corrosion inhibiting action

The molecular characteristics obtained by quantum chemical self‐consistent field (SCF) calculations of a series of quinones are correlated with the experimentally determined inhibitor efficiency for mild steel corrosion in neutral aqueous medium. It was established that the decrease of the ionization potential and the increase of the dipole moment of the quinone molecules favor the higher protective effect. The electron density and the geometric molecular structure have also been computed and are discussed in view of the corrosion inhibition.     

硬质合金基体腐蚀工艺对金刚石薄膜的影响

采用不同的预处理方式浸蚀YG6硬质合金基体表面,随后在热丝化学气相沉积装置上沉积了金刚石薄膜.用扫描电子显微镜、x射线衍射仪以及洛氏硬度计对样品进行了分析检测.结果表明:一步或两步浸蚀法都能抑制沉积过程中基体表面钴的不利影响.采用两步法,即Murakami剂30 min腐蚀碳化钨相,再用H2SO4:H2O2=3:7(体积比)混合酸腐蚀30 s去除钴相,基体表面粗糙,金刚石薄膜形核密度高,结晶质量较好,金刚石涂层与硬质合金基体结合良好.     

Bismuth ferrite bilayered thin films of different constituent layer thicknesses

Bilayered thin films consisting of (Bi_0.90La_0.10)(Fe_0.85Zn_0.15)O₃ and (Bi_0.90La_0.10)(Fe_0.90Zn_0.10)O₃ layers have been fabricated by radio frequency sputtering. Both multiferroic layers are well retained in these bilayers. Their leakage current, multiferroic properties, and fatigue behavior are largely dependent on the thicknesses of (Bi_0.90La_0.10)(Fe_0.85Zn_0.15)O₃. With an increase of the thickness in the (Bi_0.90La_0.10)(Fe_0.85Zn_0.15)O₃ layer, the leakage current density of bilayers is degraded due to different grain growth modes and an increase in oxygen vacancies, the dielectric constant (?_r) becomes larger due to the introduction of (Bi_0.90La_0.10)(Fe_0.85Zn_0.15)O₃ with a high ?_r value, and their magnetic properties are deteriorated with increasing the thickness ratios of (Bi_0.90La_0.10)(Fe_0.85Zn_0.15)O₃ with a weaker magnetization. All bilayers exhibit a good ferroelectric behavior regardless of varying thicknesses of the (Bi_0.90La_0.10)(Fe_0.85Zn_0.15)O₃ layer, while their coercive field decreases with increasing the thickness of the (Bi_0.90La_0.10)(Fe_0.85Zn_0.15)O₃ layer. An anomalous enhancement in switchable polarization is demonstrated by these bilayers, owing to the involvement of space charges accumulated at the interfaces between two constituent layers.     

SiC衬底金刚石薄膜的制备与性能表征

用热丝CVD法,以丙酮和氢气为碳源,在SiC衬底上沉积金刚石薄膜,提出了分步变参数沉积法制备超细晶粒金刚石复合薄膜的新工艺.结果表明,合理控制工艺条件的新工艺,对金刚石薄膜质量、形貌和粗糙度、薄膜与衬底间的附着力以及薄膜的摩擦系数有显著影响,金刚石薄膜的平均晶粒尺寸从3 μm减小到0.3 μm,拉曼特征峰显示超细晶粒金刚石薄膜特征,涂层附着力好,超细晶粒金刚石薄膜的表面粗糙度和摩擦系数值显著下降,对获取实用化的SiC在基体上沉积高附着强度、低粗糙度金刚石薄膜的新技术具有重要的意义.     

真空退火对Ti6Al4V合金离子注氧层表面形貌和结构的影响

采用等离子体基氧离子注入技术对Ti6Al4V合金进行表面处理.注入电压选取- 50 kV,注入剂量为4.5×1017 ions/cm2.氧离子注入后对注入样品进行不同温度的真空退火处理.真空退火后,样品表面形貌发生显著变化.随着退火温度增加,先后出现点状、条状缺陷和浅白色块状区.500℃真空退火后样品表面粗糙度变化不大,600℃真空退火后样品表面粗糙度急剧增加.真空退火导致注氧层中氧流失,并且不能在注氧层中析出结晶相.     

含镍和含钴介孔分子筛的稳定性和孔结构

以十六烷基三甲基溴化铵为模板剂,以硅酸钠、氯化镍、氯化钴等无机盐为原料,水热法合成出含Ni介孔分子筛和含Co介孔分子筛。采用XRD、FT-IR、TPR、TEM和比表面积孔径测定等方法对样品进行表征。结果表明:合成了长程有序性好的含Ni和含Co介孔分子筛;含Ni介孔分子筛的比表面积为753.3 m2/g,平均孔径为3.23 nm,750℃焙烧3 h,100℃水热处理5 d介孔结构仍然存在;含Co介孔分子筛的比表面积为744.1m2/g,平均孔径为4.44 nm,650℃焙烧后转变为虫蛀状介孔结构,750℃焙烧3 h后介孔有序性变得很差,100℃水热处理5 d后转变为虫蛀状结构。     

PZT高频陶瓷表面金属化薄膜及其结构

采用磁控溅射与真空蒸发工艺相对比的方法,分析了不同金属化薄膜及其结构对薄膜与PZT陶瓷的结合力和器件高频电学性能的影响.实验表明Cu-Ni+Ag薄膜可以改善陶瓷与金属的结合和减少反浸润发生,显著提高结合力,从而改善器件的电学性能.分析表明结合力是影响高频压电陶瓷电学性能的一个重要因素,实验得到了优化的金属化薄膜成分和结构,同时提出了相应的溅射工艺.     

Nd-Fe-B薄膜的磁控溅射法制备与组织结构

对直流磁控溅射法制备Nd-Fe-B薄膜工艺进行了研究.在不同的溅射功率、溅射气压、溅射时间等条件下制备薄膜,并对薄膜进行了AFM、XRD分析.结果表明,Nd-Fe-B薄膜的沉积速率、表面形貌及相结构与溅射功率、溅射气压、溅射时间密切相关.薄膜的沉积速率随磁控溅射功率的增加而增加,薄膜表面晶粒尺寸和表面粗糙度随溅射功率增加而增大.沉积速率随溅射气压的升高先增大后减小.低功率溅射时,薄膜中出现α-Fe、Nd2Fe14B相相对较少,随溅射功率增加,α-Fe相消失,Nd2Fe14B相增多.综合考虑各种因素,最佳溅射功率为100～130 W.     

化学涂层对玻璃表面与微颗粒耦合规律的影响(英文)

通过玻璃表面的试剂涂层与空气中微颗粒的耦合性实验发现,试剂涂层能明显改变表面与微颗粒的耦合能力,微颗粒平均粒径与采样的时间间隔、放置夹角和试剂浓度没有明显规律性联系,复合试剂耦合微颗粒的粒径比单一试剂的粒径小(2~3μm),其中吐温60粘附微颗粒的粒径最大(4~5μm),0.5%SDBS与0.5%氟碳复合试剂涂层表面粘附微颗粒数量的能力最强。每种试剂对微颗粒的粘附强度存在一个最佳范围。研究发现,复合试剂能获得单一试剂不具备的特殊物理化学性质,能有效改变固体表面与微颗粒的耦合性质。     

纳米Fe-ZnSe颗粒膜的结构与磁性

采用射频溅射法制备了纳米铁磁金属-半导体基体Fe0.35(ZnSe)0.65颗粒膜,并研究了其结构和磁特性.根据颗粒膜低场磁化率x(T)温度关系和不同温度下的磁滞回线,证实了在一定的温度范围内,颗粒膜中的纳米铁颗粒表现出磁性弛豫效应.当截止温度TB=50 K时.颗粒膜的磁性由超顺磁性转变为铁磁性.在截止温度以上,其饱和磁化强度Ms(T)温度关系符合Bloch的自旋波T3/2定律,探讨分析了自旋波常数增大的原因.     

钛中间层对改性层结构及性能的影响

用XPS和GXRD研究了铝合金等离子体基离子注入氮后再注入钛最后复合注入氮和钛改性层的成分深度分布及相结构 ,用XTEM观察了改性层截面的组织结构 ,用AFM观察了改性层的表面形貌 ,在此基础上测量了改性层的纳米硬度 ,进行了球盘摩擦磨损试验。结果表明 ,钛中间层使复合改性层的厚度有效增加 ,主要由α Ti,TiN及TiO2 组成 ,且TiN及TiO2 弥散分布在α Ti基材中 ,使表面形貌有所改善 ,使表面硬度及耐磨性明显提高。     

不同掺铁方式对TiO2薄膜光催化活性的影响

采用溶胶凝胶工艺在普通玻璃表面制备出表面掺铁与体相掺铁的TiO2 薄膜。运用SEM ,XRD和AES等技术研究了复合薄膜的表面特征。以光催化降解甲基橙溶液为模型反应 ,表征薄膜的光催化活性。结果表明 :体相掺铁时 ,薄膜的最佳n(Fe) /n(Ti)为 0 .12 %;表面掺铁时 ,薄膜的最佳n(Fe) /n(Ti)为 1.5 %。表面掺铁薄膜的最佳光催化表观速率常数比体相掺铁的最佳值要高 1.5倍。并从载流子分离效率等方面进行了机理探讨。     

Approaching the limits of dielectric breakdown for SiO2 films deposited by plasma-enhanced atomic layer deposition

This study explores the ultimate limit in dielectric breakdown of SiO₂ thin films deposited by gas-phase, plasma-enhanced atomic layer deposition. Thickness-dependent breakdown behaviors similar to conventional, thermally grown SiO₂ thin films were observed for the first time on ALD films, where the dominant breakdown mechanisms were impact ionization, trap creation and anode hole injection, respectively. By suppressing these mechanisms, we show a reversible degradation in SiO₂ after the onset of Fowler–Nordheim tunneling before permanent dielectric damage occurs. The reversible window was only observable in films thinner than 10 nm. The SiO₂ thin films ultimately reached irreversible breakdown at a field strength of 2.7 V nm^?1, where Si–O bonds were destroyed due to impact ionization and accelerated electrons.