磁过滤电弧离子镀TiN与N离子注入性能研究

目的研究磁过滤电弧离子镀TiN与N离子注入对金属基体的保护效果。方法采用磁过滤电弧离子镀和离子注入在不锈钢表面分别制备了TiN薄膜与N注入改性层,以及二者的复合膜层。对薄膜的相结构、微观形貌进行了表征,对薄膜进行了极化曲线测试,同时在半球样品表面制备涂层并进行盐雾测试。结果所制备的TiN涂层为(111)晶面择优取向,离子注N预处理后沉积的TiN薄膜,仍保持(111)面的择优取向;电化学测试结果显示,TiN和N离子注入能够使不锈钢基体自腐蚀电位分别提高0.64、0.25 V,TiN薄膜具有最低的维钝电流密度4.9×10^(-6) A/cm^(2),N离子注入+TiN复合薄膜的维钝电流密度与N离子注入样品接近;盐雾试验结果表明,TiN以及N离子注入+TiN复合薄膜样品能够保证铜半球在12h的中性盐雾试验中无明显腐蚀痕迹。结论N离子注入预处理对MFAIPTiN涂层耐蚀性能的提升效果有限,单一的MFAIP TiN涂层便可应用于复杂形状的工程材料表面镀膜,可以增强其抗腐蚀能力,延长使用寿命。

EXPERIMENTAL STUDY ON SUPERFICIAL COAT OF GEARS OF NITRIDED 32Cr2MoV COATED WITH TiN FILM BY MULTI-ARC ION PLATING

After 32CrMoV is selected to manufacture nitrided gears coated with TiN by multi-arc ion plating, all of these uncoated gears and coated gears run in the gearbox under the same initial conditions so as to compare their difference concerning properties and microstructure. Experiment results indicate that tooth surface of the coated-TiN gears does not suffer surface abnormalities in meshed zone. Instead, the gears with nitrided case exhibit an abrasion mark on the meshed zone of tooth surface, which results in more weight loss of nitrided gears. The morphology of the surface suggests TiN film with more than 2 000 HV is so dense and smooth that coated-TiN gears have higher wear resistance compared with the uncoated gears. The microstructure of coated-TiN gears is finer, hardness is higher and its distribution of coated-TiN gears is more reliable than uncoated ones, which makes nitride layer combined with TiN film tightly. Consequently, the wear-resistance of gears has been dramatically promoted.

光栅阀角度对电弧离子镀TiN薄膜结构及性能的影响

通过调整光栅阀角度开展对电弧离子镀TiN薄膜结构及力学性能的研究。实验结果表明:光栅阀角度对TiN薄膜的择优取向无明显影响,薄膜均以TiN(200)面择优取向为主;随着光栅阀角度的增加,TiN薄膜中N与Ti原子比均呈欠化学计量比,且先增加而后降低,在光栅阀角度为10°时N与Ti原子比最高;TiN薄膜表面粗糙度随着光栅阀角度增加整体呈增加趋势;在光栅阀角度为10°时,TiN薄膜呈现出最高硬度和最低磨损率,具有最佳力学和耐磨性能。在电弧离子镀真空镀膜过程中,光栅阀角度通过影响气体流量进而影响薄膜性能,但对于TiN薄膜结构无明显影响,只有选择合适的光栅阀角度才能有助于薄膜综合性能的改善。

Preparation of Highly Dispersed Antimony-doped Tin Oxide Nano-powder via Ion-exchange Hydrolysis of SnCl_4 and SbCl_3 and Azeotropic Drying

Antimony-doped tin hydroxide colloid precipitates have been synthesized by hydrolysis of SnCl4 and SbCl3 using： （1） an ion-exchange hydrolysis to remove chlorine ions, and （2） isoamyl acetate as an azeotropic solvent to obviate water. The obtained dried powder is of high dispersivity without any need for further grinding. The size and dispersivity of the final particles are investigated with the aid of TG-DTA, BET, XRD and TEM. After having calcined, the antimony-doped tin oxide nanopowder possesses a tetragonal rutile structure with high dispersivity, uniform particles and low hard agglomeration.

IMPROVEMENT OF ADHESION BETWEEN ION PLATED TiN COATING AND BASE METAL BY ADDING Y

The adhesion between the ion plated TiN coating and the base metal is improved by adding Y.The machenism of the effect of Y has been discussed as well.

Effect of Rare Earth Element Cerium on Mechanical Properties and Morphology of TiN Coating Prepared by Arc Ion Plating

TiN coatings were deposited on polished substrates of W18Cr4V high speed steel by means of vacuum arc ion plating. The effect of cerium on adhesion between TiN coating and substrate was studied. The microstructures and composition of TiN coatings were also investigated by means of scanning electron microscope (SEM), Auger electron spectroscopy (AES), and X ray diffraction (XRD) technique. It was found that cerium is an effective modifying agent and the addition of suitable amount of cerium to TiN coatings can produce relatively excellent properties such as micro hardness, wear resistance, oxidation resistance and porosity. The experimental results show that the added cerium in TiN coatings makes a contribution to form the preferred direction along with a (111) or (222) close packed face, which may be one of the reasons that improves some properties mentioned above.

Experimental Verification of the Physical Model for Droplet-Particles Cleaning in Pulsed Bias Arc Ion Plating

It has been reported that application of pulsed biases in arc ion plating could effectively eliminate droplet particles. The present paper aims at experimental verification of a physical model proposed previously by us which is based on particle charging and repulsion in the pulsed plasma sheath. An orthogonal experiment was designed for this purpose, using the electrical parameters of the pulsed bias for the deposition of TiN films on stainless steel substrates. The effect of these parameters on the amount and the size distribution of the particles were analyzed, and the results provided sufficient evidence for the physical model.

Preparation of tin-oxide nanotubes as anode for Li-ion batteries

The influence of nanostructure on the electrochemical properties of Li-ion battery was investigated. Tin-oxide nanotubes were prepared by combining sol-gel method with polycarbonate template. Scanning electron microscopy and X-ray diffractometry were applied to characterize the obtained material. The electrochemical measurements were conducted on the nanostructured tin-oxides as electrode of Li-ion batteries. The XRD data indicate that the wall of tube is composed of cassiterite crystals of several nanometers. The electrochemical measurements show that the reaction under potential 0.1-0.2 V is possibly related to the tubular structure of the material. It is suggested that the trapping of Li by dangling bonds and defects sites also contributes to the larger irreversible capacity loss in the first discharge.

Surface Modification of PVD-TiN Films Using MEVVAIon Implantation

Ti ion implantation was implanted into PVD-TiN films using a metal vapor vacuum arc (MEVVA) ion source with a low implantation dose and at a time-averaged ion beam current density of 25|O.A-cm’2. The wear characteristics of the implanted zone was measured and compared to the performance of unimplanted zone by a pin-on-disc apparatus and an optical interference microscope. The structure of the implanted zone and unimplanted zone was observed by X-ray photoelectron spectroscopy (XPS) and high voltage electron microscopy (HVEM). The wear mechanisms of the TiN film after ion implantation were discussed according to the results of XPS and HVEM.

Tin oxide-graphite composite for lithium storage material in lithium-ion batteries

A SnO-graphite composite material, which can deliver high capacities and good cycling stability compared with unsupported SnO, was described. This material prepared via chemical co-precipitation reaction in the presence of graphite consists of high dispersion of SnO with a size of about several hundred nanometers in the graphite. The phase structure was analyzed by X-ray diffraction (XRD). The morphology and the element distribution were examined by scanning electron microscopy (SEM) equipped with energy spectrum. The results show that the SnO-graphite composites produced by slowly hydrolysis have higher rechargeable capacities than pure graphite and better cycling performance than SnO.

PREPARATION OF TiN FILMS BY N_2 ASSISTED Xe^+ ION BEAM ENHANCED DEPOSITION AND THEIR MECHANICAL PROPERTIES

A new method for preparation of hard TiN films has been developed by using electron beam evaporation-deposition of Ti and bombardment with 40 keV Xe^+ ion beam in a N_2 gas environment.The synthesized TiN films were superior to PVD and CVD ones in respects of improved adhesion to substrate and low preparing temperature.They exhibited good wear resistance and high hardness up to 2200 kg/mm^2.Some industrial applications have been reported.

SYNTHESIS OF TiN FILM WITH ION BEAM ENHANCED DEPOSITION AND ITS PROPERTIES

The TiN films were synthesized with an alternate process of depositing titanium from a E-gun evaporation source and 40 keV N^+ bombarding onto the target.It is shown from the composi- tion analysis and structure investigations using RBS,AES,TEM,XPS and X-ray diffraction spectrum that the formed fihns are mainly composed of TiN phase with grain size of 30—40 nm and without preferred orientation,the nitrogen content in the film is much less than that in case without N^+ bombarding,and an intermixed region about 40 nm thick exists between the film and the substrate.The films exhibt high microhardness and low friction. ZHOU Jiankun,Ion Beam Laboratory,Shanghai Institute of Metallurgy,Academia Sinica, Shanghai 200050,China

Mesoporous Carbon-Tin Nanocomposites as Anode Materials for Li-ion Battery

A new mesoporous carbon-tin （MC-Sn） nanocomposite has been successfully prepared via a two-step method. From the transmission electron microscopy （TEM） observations, the tin nanoparticles were decorated on the as-prepared mesoporous carbons. The mesoprous structure of the carbon can effectively buffer the volume changes during the Li-Sn alloying and de-alloying cycles. The as-prepared MC/Sn nanocomposite electrodes exhibited extremely good cycling stability, with the specific capacity of Sn in the composite electrode calculated to be 959.7 mAh-g-1, which amounts to an impressive 90.9% of the theoretical value （990 mAh-g-1）. The reversible capacity after 200 cycles is 96.1% of the first cycle reversible capacity, i.e., the capacity fade rate is only 0.0195% per cycle, which is even better than that of commercial graphite-based anodes.

Study on the Properties of TiN Coatings on Previously Ion-Implanted Pure Magnesium Surface by MEVVA Ion Implantation

A metal vapor vacuum arc （MEVVA） is used in ion implantation for substrate preparation before the deposition process which would ensure the improvement of mechanical properties of the coating. Ti ion is implanted into pure magnesium surface by MEVVA implanter operated with a modified cathode. Implanting energy is kept at 45 keV and dose is set at 3 ×10^17 cm^-2. TiN coatings are deposited by magnetically filtered vacuum-arc plasma source on unimplanted and previously implanted substrates. Microstructure and phase composition are analysed using scanning electron microscopy （SEM） and X-ray diffraction （XRD）. The property of corrosion resistance of TiN coatings was studied by CS300P electrochemistry-corrosion workstation, and the main impact factor of the corrosion resistance was also analyzed.

Degradation mechanism of tin phosphide as Na-ion battery negative electrode

The degradation mechanism of an Sn_4P_3 electrode as Na-ion battery anode was investigated by using a transmission electron microscopic observation. At the first desodiation, we confirmed that Sn nanoparticles with 6 nm in size were dispersed in an amorphous-like P matrix.Compared to this, we observed aggregated Sn particles with sizes exceeding 50 nm after the drastic capacity fading. The capacity fading mechanism was for the first time confirmed to be Sn aggregation. To improve the capacity decay, we carried out the two kinds of chargeàdischarge cycling tests under the reduced volume changes of Sn particles and P matrix by limiting desodiation reactions of Nae Sn and Na3P, respectively. The Sn_4P_3 electrode exhibited an excellent cyclability with the discharge capacity of 500 mA hg^(-1) for 420 cycles under the limited desodiation, whereas the capacity decay was accelerated under the limited sodiation. The results suggest that the Sn aggregation can be improved by the reduced volume change of the P matrix, and that it is very effective for improving anode performance of Sn_4P_3 electrode.

Effect of Sample Configuration on Droplet-Particles of TiN Films Deposited by Pulse Biased Arc Ion Plating

Orthogonal experiments are used to design the pulsed bias related parameters, including bias magnitude, duty cycle and pulse frequency, during arc ion deposition of TiN films on stainless steel substrates in the case of samples placing normal to the plasma flux. The effect of these parameters on the amount and the size distribution of droplet-particles are investigated, and the results have provided sufficient evidence for the physical model, in which particles reduction is due to the case that the particles are negatively charged and repulsed from negative pulse electric field. The effect of sample configuration on amount and size distribution of the particles are analyzed. The results of the amount and size distribution of the particles are compared to those in the case of samples placing parallel to the plasma flux.

Preparation and electrochemical properties of nanosized tin dioxide electrode material by sol-gel process

Nanosized SnO 2 powders were prepared by sol gel process using inorganic salt as a precursor. The tin oxide powders obtained at different calcinating temperatures (300700 ℃) were investigated by means of X ray diffraction(XRD), infrared spectrum (IR), thermogravimetric analysis (TGA), differential thermal analysis (DTA) and transmission electron microscopy (TEM) as well. The results indicate that well crystallized nanosized SnO 2 powders with a structure of rutile and uniform size about 10 nm can be obtained when the calcinating is carried out at 550 ℃ for 3 h using the method. The electrochemical properties of nanosized SnO 2 powders as anode material for lithium ion batteries were also studied in detail. The results show that nanosized SnO 2 is a candidate of anode material for lithium ion batteries with reversible capacity more than 372 mA·h/g after ten cycles and low voltage for Li + intercalation and de intercalation.

A new Tin-based O3-Na_(0.9)[Ni_(0.45-x/2)Mn_xSn_(0.55-x/2)]O_2 as sodium-ion battery cathode

Recently,sodium-ion batteries(SIBs),regarded as promising supplements for lithium-ion batteries(LIBs),especially in the large-scale energy storage field,are attracting more and more attention.However,the limited suitable cathode materials hinder the wide commercialization of SIBs.Given this aspect,in this work,a new layered oxide with 4d metal Tin was synthesized and investigated as cathode material for SIBs.Two optimized sodium-deficient O3-Na_(0.9)Ni_(0.45)Sn_(0.55)O_2and O3-Na_(0.9)Ni_(0.4)Mn_(0.1)Sn_(0.5)O_2were selected for comprehensive investigation,both of which exhibited high operating voltage of around 3.45 V with smooth charge/discharge curves.In comparison,O3-Na_(0.9)Ni_(0.4)Mn_(0.1)Sn_(0.5)O_2shows a higher reversible capacity(65 m A h/g,0.1 C),better rate capability and cycling stability than that of O3-Na_(0.9)Ni_(0.45)Sn_(0.55)O_2(50 mA h/g,0.1 C),indicating that a small amount of Mn-substitution can improve the electrochemical performance.This work presents a new possibility of discovering potential cathode candidates by exploring the Tin-based layered oxides.

不同工艺参数对TiN薄膜形貌和力学性能的影响

随着硬质薄膜的快速发展,TiN薄膜已经在诸多领域成功应用。通过采用PVD多功能离子镀膜机在不同工艺参数条件下制备了TiN薄膜,研究不同工艺参数对TiN薄膜表面大颗粒形貌和力学性能的影响。利用扫描电子显微镜对TiN薄膜的表面形貌进行研究,利用球坑仪、划痕仪和显微硬度计对薄膜的力学性能进行分析。研究结果表明,弧电流越大,大颗粒尺寸越大,薄膜厚度及硬度也会显著增加;当沉积温度升高时,TiN表面大颗粒的尺寸与数量显著减小,结合强度出现先增加后减小的趋势;当负偏压增大时,TiN薄膜表面大颗粒出现了先减少后增多的趋势,而薄膜的厚度和硬度也会相应降低。该研究为生产中制备性能优良的TiN薄膜提供了一定的理论依据。

Effects of SiO_2 and TiO_2 on resistance stabilities of flexible indium-tin-oxide films prepared by ion assisted deposition

Inorganic buffer layers such as SiO2 or TiO2 and transparent conductive indium-tin-oxide （ITO） films were prepared on polyethylene terephthalate （PET） substrates by ion assisted deposition （IAD） at room temperature, and the effects of SiO2 and TiOzon the bending resistance performance of flexible ITO films were investigated. The results show that ITO films with SiO2 or TiO2 buffer layer have better resistance stabilities compared to ones without the buffer layer when the ITO films are inwards bent at a bending radius more than 1.2 cm and when the ITO films are outwards bent at a bending radius from 0.8 cm to 1.2 cm. 1TO films with SiO2 buffer layer have better resistance sta- bilities compared to ones with TiO2 buffer layer after the ITO fdms are bent several hundreds of cycles at the same bending radius, for the adhesion of SiO2 is stronger than that of TiO2. The compressive stress resulted from inward bending leads to the formation of more defects in the ITO films compared with the tensile stress arising from outward bending. SiO2 and TiO2 buffer layers can effectively improve the crystallinity of ITO films in （400）, （440） directions.