磁过滤真空弧等离子体钛沉积膜的XPS研究

通过磁过滤真空弧等离子体沉积技术 ,在单晶Si和H13钢衬底上生长一层Ti沉积膜。利用扫描电镜、X射线衍射仪和X射线光电子能谱仪对膜层进行了测量和分析。结果表明 ,加上磁过滤器的沉积膜表面平整光洁 ,无“液滴”出现。在靶室真空度不高的情况下 ,膜层中的Ti以TiO的形式存在 ,并且TiO晶粒沿 <110 >方向择优取向。膜层表面的TiO进一步与大气中氧发生反应形成TiO2 。

承钢高炉炉缸高铝高钛沉积物的物化性能

采用电子探针仪测定了承钢高炉炉缸高铝高钛沉积物的化学组成,利用显微镜对其进行矿相分析,并用扫描电镜观察该沉积物中主要元素的分布形态。研究结果可为进一步分析承钢高炉炉缸沉积物形成机理奠定基础。

磁过滤真空弧等离子体钛沉积膜改善H13钢腐蚀机理的研究

利用磁过滤真空弧等离子体沉积成膜系统 ,在H13钢基体上沉积一层 36 0nm的钛膜。透射电镜 (TEM)分析结果表明 ,沉积膜膜层的微观结构呈晶须状。在 pH =5.6的NaAc/HAc缓冲液中阳极极化扫描曲线测量表明 ,沉积膜样品的腐蚀电流密度峰值较H13钢降低 1— 2个数量级 ,抗腐蚀性能大幅度提高 ,离子注入进一步降低了沉积膜样品的峰值腐蚀电流密度 ,提高了沉积膜样品的抗腐蚀性。SEM对腐蚀样品的表面形貌进行了分析 ,并对沉积膜样品的抗腐蚀机理进行了研究。

超薄钛沉积石墨烯基传感器室温氨气响应性能研究

本征石墨烯气体传感器(Gr器件)对NH_3气体的室温响应非常微弱,为此本文采用电子束蒸镀方法在原器件沟道区域分别沉积3 nm、5 nm和10 nm的薄层金属Ti,形成三种Ti/Gr器件。实验发现Ti/Gr器件在黑暗条件下对NH3气体的室温响应灵敏度远高于Gr器件;而引入可见光照射使三种Ti/Gr器件的响应灵敏度进一步提高,同时恢复性也得到一定提升。其中,5 nm Ti/Gr器件获得最佳的性能提升,对通入3 min 400×10^-6 NH3的灵敏度达+17.9%,恢复时间为3 min。通过XPS分析,发现不同Ti/Gr器件沟道处所沉积的薄层Ti发生不同程度的氧化,生成包含不同价态成份的钛氧化物,导致特定Ti层厚度的Ti/Gr器件具有最佳性能。

酒钢1~#高炉缸砖衬破损原因及钛沉积物的护炉作用

With modern means of analyses,the compositions of samples from the damaged brick lining of blast furnace No.1 and its damage mechanism are researched.The results are helpful for the improvement of furnace material structure and operation technology.

一个新的沉积变质型钛矿床的成矿模式及找矿方法

内蒙古羊蹄子山沉积变质型钛矿床是一个新的钛矿床类型。通过对地质、地球物理前提条件的研究和找矿方法试验,认为高精度磁法是找沉积变质型钛矿床的基本方法,重力为有效的找矿方法。在矿区北带磨石山以金红石为主的富钛矿体上有600μGal的重力异常,无磁异常;南带的羊蹄子山钛铁矿体上重力异常为500μGal,有60nT的弱磁异常。

四川某沉积型钛矿化学选矿工艺探讨

沉积型锐钛矿在钛资源选矿技术发展中长期以来基本处于空白状态,甚至被业内研究人员认为是呆滞资源。四川某含铁高岭土型锐钛矿为典型的该类矿石,含TFe 18.88%、TiO_(2)6.19%、Al_(2)O_(3)21.39%。本文针对该矿石性质,进行了不同硫酸浸出工艺的化学选矿探索性实验。实验结果表明,硫酸化焙烧-水浸工艺和硫酸直接浸出工艺均能对矿石中钛和铝有较好的浸出效果。探索实验获得的浸出实验结果:钛浸出率分别为68.66%、52.78%,铝铁浸出率均在90%以上。实验结果为该类沉积型钛矿的利用指明了方向。

根据钛平衡计算分析含钛炉料护炉的控制思路

结合唐钢1号高炉生产实践,根据钛平衡计算获得含钛炉料护炉过程中炉缸钛沉积量,发现炉缸侧壁特征温度均值变化与炉缸钛沉积量密切相关。通过应用数理统计学方法对生产实践中炉料钛负荷、[Ti]、钛的收得率、(TiO_2)与炉缸钛沉积量的相关关系进行分析,找到影响高炉含钛炉料护炉效果的关键因素,总结出含钛炉料护炉的控制思路。

兴澄3200m^(3)高炉钛矿护炉若干因素探析

结合兴澄3200m^(3)高炉两个阶段的钛矿护炉实践,对护炉过程中钛平衡、风口布局、造渣制度和出铁口环流等因素进行了探讨。第二阶段按照[Ti]0.08%-0.10%,钛负荷3~4kg/t控制,护炉效果优于第一阶段。认为适当提高炉渣二元碱度、降低(或局部降低)铁水环流、保持合适稳定的冶炼强度,是增加炉缸钛沉积量的有利途径,并指出低[Ti]护炉是今后研究的一个重要方向。

钛矿护炉对首钢股份1号高炉生产的影响

阐述了首钢股份1号高炉钛矿护炉期间各生产指标,如风量、冶炼强度、燃料比、铁水温度、[Ti]及炉缸炉底钛沉积量等的变化状况。钛矿护炉为期10天,钛矿配加量由常规护炉的1.5t/批,提升至强化护炉的2.5t/批;风量由4777m^(3)/min减小到4744m^(3)/min,透气性明显变差;冶炼强度出现小幅度下降;燃料比未出现明显变化;铁水温度及[Si]都出现了不同程度的下降。在钛矿护炉前期,[Ti]含量呈现出明显的上升趋势,炉缸炉底钛沉积量在短时间内由2t/d上升到14t/d左右,容易引起炉况波动,应该密切关注炉况的变化。

Influence of anodization conditions on deposition of hydroxyapatite onα/βTi alloys for osseointegration:Atomic force microscopy analysis

Integrating titanium-based implants with the surrounding bone tissue remains challenging.This study aims to explore the impact of different anodization voltages(20−80 V)on the surface topography of two-phase(α/β)Ti alloys and to produce TiO_(2) films with enhanced bone formation abilities.Scanning electron microscopy coupled with energy dispersive spectroscopy(SEM−EDS)and atomic force microscopy(AFM)were applied to investigate the morphological,chemical,and surface topography of the prepared alloys and to confirm the growth of hydroxyapatite(HA)on their surfaces.Results disclosed that the surface roughness of TiO_(2) films formed on Ti−6Al−7Nb alloys was superior to that of Ti−6Al−4V alloys.Ti−6Al−7Nb alloy anodized at 80 V had the highest yields of HA after immersion in simulated body fluid with enhanced HA surface coverage.The developed HA layer had a mean thickness of(128.38±18.13)μm,suggesting its potential use as an orthopedic implantable material due to its promising bone integration and,hence,remarkable stability inside the human body.

TiB_2/Ni coatings on surface of copper alloy electrode prepared by electrospark deposition

In order to improve the lifespan of spot-welding electrodes used for welding zinc coated steel sheets, titanium diboride was deposited onto their surface after precoating nickel as an intermediate layer. The microstructures and phase compositions of TiB2 and Ni coatings were characterized by SEM and XRD. The coating hardness was measured using a microhardness tester. The results indicate that a satisfactory TiB2 coating is obtained as a result of the intermediate nickel layer acting as a good binder between the TiB2 coating and the copper alloy substrate. Owing to its capacity of deforming, the precoated nickel layer is dense and crack free, while cracks and pores are observed in the TiB2 coating. The hardness of the TiB2/Ni coating decreases with the increase of voltage and capacitance because of the diffusion of copper and nickel and the oxidation of the coating materials. Because of the good thermal and electrical conductivities and high hardness properties of TiB2, the deformation of the electrode with TiB2/Ni coating is reduced and its spot-welding life is by far prolonged than that of the uncoated one.

Microstructure evolution of laser deposited Ti60A titanium alloy during cyclic thermal exposure

Cyclic thermal exposure tests of infrared heating to 800 ℃ in 120 s followed by compressed air cooling to 150 ℃ in 60 s were performed for the laser deposited Ti60A （Ti5.54Al3.38Sn3.34Zr0.37Mo0.46Si） alloy. The effects of thermal exposure cycles on length ofβphase, area fraction ofαphase and microhardness of alloy were examined by OM, SEM and EDS. The results indicate that thermal exposure cycles have significant effects on length ofβphase, area fraction ofαphase and microhardness of the alloy. The original fine basket-weaveβand 78.5%αtransform to transient wedge-likeβ, finally leaving granularβand 97.6%coarsenedαwith the increased thermal exposure cycles. The formation mechanism of coarsenedαand broken-upβmicrostructure is discussed. The alloy after 750 thermal exposure cycles has the maximum microhardness, 33.3%higher than that of the as-deposited alloy.

Effects of nitrogen flux on microstructure and tribological properties of in-situ TiN coatings deposited on TC11 titanium alloy by electrospark deposition

In order to improve the tribological properties of titanium alloys,the in-situ TiN coatings were prepared by electrospark deposition（ESD） on the surface of TC11 titanium alloy.The effects of nitrogen flux on the microstructure and tribological properties of TiN coatings were investigated.The results show that the coating is relative thin when the nitrogen flux is small and mainly consists of Ti2N,α-Ti,Ti O and TiN phases,and the metastable phase of Ti2N is developed due to the rapid solidification of ESD.While in excessive nitrogen flux condition,many micro-cracks and holes might be generated in the coating.In moderate nitrogen flux,the coating is mainly composed of TiN phase,and is dense and uniform（50-55 μm）.The average hardness is HV0.2 1165.2,which is 3.4 times that of the TC11 substrate.The TiN coatings prepared in moderate nitrogen flux perform the best wear resistance.The wear loss of the coating is 0.4 mg,which is 2/9 that of the TC11 substrate.The main wear mechanisms of the coatings are micro-cutting wear accompanied by multi-plastic deformation wear.

Fabrication of titanium oxide films at low temperature from aqueous solution

Titanium oxide thin films were prepared on self-assembled monolayers-coated silicon substrate using layer-by-layer self-assembly method and chemical bath deposition from an aqueous solution. The effects of temperature on structural properties, thickness and morphologies of titanium oxide thin films were investigated. The results show that the absorption peak of peroxo complexes of titanium at 410 nm decreases gradually with increasing the temperature. The deposited films consisting of titanium oxide nanocrystals are believed to be fully amorphous by XRD. Titanium oxide thin films fabricated at 60 °C for 2 h are continuous, dense and homogeneous with a size in the range of 20-40 nm by SEM. The chemical compositions of deposited thin films were studied by EDS, and the mole ratio of O to Ti is 2.2：1.

Growth and crystallization behaviors of anodic oxide films on sputter-deposited titanium at very low potentials

Growth and crystallization of titanium anodized films were studied by performing the anodization of the sputter-deposited titanium samples under cyclic voltammetry （CV） mode at very low potentials. The surface features, crystalline behaviors and chemical compositions of the formed anodic oxide layers were detected by AFM, SE and XPS. It was found that the structure of the titanium anodized films is crystalline, even though the maximum oxidation potential （（Pmax） is very low （as low as 1000 mY）. Both enlarging the applied voltage and reducing the potential scanning rate are beneficial for the growth and crystallization of titanium oxide films. It was thought that the internal compressive stress, other than the local joule heating accepted for many researchers, is the main force of stimulating the crystallization of anodic titanium oxide films at very low potentials.

Synthesis of Various Metal/TiO2 Core/shell Nanorod Arrays

We present a general approach to fabricate metal/TiO2 core/shell nanorod structures by twostep electrodeposition. Firstly, TiO2 nanotubes with uniform wall thickness are prepared in anodic aluminum oxide （AAO） membranes by electrodeposition. The wall thickness of the nanotubes could be easily controlled by modulating the deposition time, and their outer diameter and length are only limited by the channel diameter and the thickness of the AAO membranes, respectively. The nanotubes＇ tops prepared by this method are open, while the bottoms are connected directly with the Au film at the back of the AAO membranes. Secondly, Pd, Cu, and Fe elements are filled into the TiO2 nanotubes to form core/shell structures. The core/shell nanorods prepared by this two-step process are high density and free-standing, and their length is dependent on the deposition time.

Preparation of TiO_2/ITO film by liquid phase deposition and its photoelectrocatalytic activity for degradation of 4-aminoantipyrine

A thin layer of TiO2 film was deposited on ITO surface via the liquid phase deposition （LPD） process. The photocurrent and electrochemical impedance spectroscopy （EIS） measurements indicated that the as-prepared LPD TiO2/ITO film had an excellent photoelectrochemical performance, which showed a sensitive and rapid response to the UV irradiation. The photogenerated electron-hole pairs could be effectively separated by applying an external bias to the TiO2 film electrode. The LPD TiO2/ITO film was employed to study the photoelectrocatalytic （PEC） degradation of 4-aminoantipyrine. Compared with other techniques, the PEC technique based on such a LPD film electrode had a synergetic effect for 4-aminoantipyrine degradation. When the applied bias potential was＋0.8 V and the supporting electrolyte concentration of Na2SO4 was 0.1 mol/L, the highest degradation efficiency within 120 min could reach 95%for 0.1 mmol/L 4-aminoantipyrine solution at pH 2.0.

Low cycle fatigue behavior of laser melting deposited TC18 titanium alloy

Low cycle fatigue （LCF） behavior of laser melting deposited （LMD） TC18 titanium alloy was studied at room temperature. Microstructure consisting of fine lamella-like primary α phase and transformed β matrix was obtained by double annealed treatment, and inhomogeneous grain boundaryαphase was detected. Fatigue fracture surfaces and longitudinal sections of LCF specimens were examined by optical microscopy and scanning electron microscopy. Results indicate that more than one crack initiation site can be detected on the LCF fracture surface. The fracture morphology of the secondary crack initiation site is different from that of the primary crack initiation site. When the crack grows along the grain boundaryαphase, continuous grain boundaryαphase leads to a straight propagating manner while discontinuous grain boundaryαphase gives rise to flexural propagating mode.

Fabrication of TiN/cBN and TiC/diamond coated particles by titanium deposition process

Cubic boron nitride particles coated by titanium nitride (TiN/cBN) as well as diamond particles coated by titanium carbide (TiC/diamond) were prepared by Ti molten salt deposition followed by heat-treatment process. cBN or diamond particles were mixed separately with Ti powders and molten salts (KCl, NaCl and K2TiF6). The mixture was heated at 900 °C under argon atmosphere. The produced particles were heat-treated under hydrogen at 1000 °C. The morphologies and chemical compositions of the produced particles were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD) and focused ion beam (FIB). The results show that the cBN and the diamond particles are coated by nano-sized Ti layers. By heat-treatment of the Ti/cBN and TiC/diamond coated particles under hydrogen atmosphere, the deposited Ti layers were interacted by the in-situ transformation reaction with the surfaces of cBN and diamond particles and converted to titanium compounds (TiN and TiC), respectively.