Properties of Zr-ZrC-ZrC/DLC gradient films on TiNi alloy by the PIIID technique combined with PECVD

The Zr-ZrC-ZrC/DLC gradient composite films were prepared on TiNi alloy by the techniques combined plasma immersion ion implantation and deposition (PIIID) and plasma enhanced chemical vapor deposition (PECVD). With this method, the Zr-ZrC intermixed layers can be obtained by the ion implantation and deposition before the deposition of the ZrC/DLC composite film. In our study, an optimal gradient composite film has been deposited on the NiTi alloys by optimizing the process parameters for implantation and deposition. The surface topography was observed through AFM and the influence of the deposition voltage on the surface topography of the film was investigated. XPS results indicate that on the outmost layer, the Zr ions are mixed with the DLC film and form ZrC phase, the binding energy of C 1s and the composition concentration of ZrC depend heavily on the bias voltage. With the increase of bias voltage, the content of ZrC and the ratio of sp³/sp² firstly increases, reaching a maximum value at 200 V, and then decreases. The nano-indentation and friction experiments indicate that the gradient composite film at 200 V has a higher hardness and lower friction coefficient compared with that of the bare NiTi alloy. The microscratch curve tests indicate that gradient composite films have an excellent bonding property comparing to undoped DLC film. Based on the electrochemical measurement and ion releasing tests, we have found that the gradient composite films exhibit better corrosion resistance property and higher depression ability for the Ni ion releasing from the NiTi substrate in the Hank's solution at 37°C.     

Structure and tribological properties of modified layer on 2024 aluminum alloy by plasma-based ion implantation with nitrogen/titanium/carbon

1　INTRODUCTIONGoodmachinability ,lowdensityandhighspecif icstrengthmakealuminumanditsalloysextensivelybeusedinmanyindustries ,especiallyinaviationandspaceflightindustry .Howeverlowsurfacehardnessandlowwearresistanceoftenlimittheirengineeringapplications .Nitrogenionimplantationintoalu minumanditsalloysoffersthepossibilityofapplica tionswherebothhighwearresistanceandlowdensityarerequired[15] .Moreover ,ourpreviousinvestiga tion[6 ,7] presentedthatwhenaluminumalloywasim plantedwithnitrogen…     

NiTi合金表面类金刚石膜的表面特征和腐蚀行为

采用等离子浸没离子注入和沉积（PIIID）法以C2H2为等离子源对NiTi合金进行表面改性。利用Raman光谱分析膜层结构。采用原子力显微镜和纳米压痕分析涂层前后NiTi的表面形貌和力学性能。利用电化学测试、扫描电镜和原子吸收光谱测试涂层前后基体的耐腐蚀性和Ni离子析出。结果表明：NiTi合金表面的膜层是类金刚石（DLC）；经过PIIID处理后，基体表面的粗糙度降低；纳米硬度得到提高；耐腐蚀性能获得明显改善；Ni离子析出得到有效的抑制。     

水分子诱导类金刚石薄膜表面的变化

利用等离子体增强化学气相沉积技术在单晶硅表面制备了类金刚石(DLC)薄膜,并将其分别浸泡在经磁场处理和未经磁场处理的去离子水中。利用X射线光电子能谱仪、原位纳米力学测试系统和高速摩擦磨损测试仪分析和比较在水和磁化水中浸泡后DLC薄膜表面的变化情况。结果表明:磁场作用将改变经过DLC薄膜表面微孔或缺陷渗进薄膜内的水分子个数,进而诱导DLC薄膜表面发生变化。在含水环境中,比如液体水中,水分子参与反应并诱导C=C键朝向C-C或C-H键转化,并且氢原子将进入薄膜内中和膜内自由基,进而导致其硬度,摩擦因数升高。     

Characteristics of phosphorus-doped diamond-like carbon films synthesized by plasma immersion ion implantation and deposition (PIII and D)

Plasma immersion ion implantation and deposition (PIII and D) is an effective approach to synthesize high quality thin films for different industrial applications. This dual implantation and deposition process can produce a graded layer that mitigates delamination and poor adhesion. In this work, phosphorus-doped diamond-like carbon (DLC) films were synthesized by PIII and D. Thin DLC films with various phosphorus concentrations were produced by using different experimental parameters. The chemical composition was determined by X-ray photoelectron spectroscopy (XPS) and electron energy loss spectroscopy (EELS). Micrographs obtained by cross-sectional transmission electron microscopy (X-TEM) reveal good adhesion between the films and substrates. The biocompatibility was evaluated using platelet adhesive tests. The results show that the sample doped with an optimal amount of phosphorus exhibits less platelet adhesive and activation, and the overall results are better than that observed on low-temperature isotropic pyrolytic carbon (LTIC). Phosphorus-doped DLC films thus have potential applications in blood contacting medical devices.     

射频辉光放电等离子体辅助化学气相沉积法制备类金刚石碳膜工艺与性能表征

使用射频辉光放电等离子体辅助化学气相沉积技术（简称RFGDPECVD）在玻璃载玻片表面沉积类金刚石薄膜。用原子力显微镜（AFM）、摩擦试验仪、划痕试验机测定了其表面形貌、耐磨性及附着性。采用X射线光电子能谱（XPS）、分光光度计对两种气源（C4H10、C2H2）制备的DLC薄膜微观组成和透光率进行了检测和对比。结果表明：DLC薄膜的表面光滑、平整,表面粗糙度随沉积时间的增加单调递增;耐磨性及附着性优良;与C4H10相比使用C2H2作为碳源气体可以得到较高Sp^3含量和较低Sp^1含量的DLC膜;C2H2制备DLC薄膜的透光率低于C4H10;同一种碳源气体,反应流量比例越小,则DLC薄膜的透光性越好。     

Effect of metallic interfacial layers on the properties of diamond-like carbon thin films

Diamond like carbon (DLC) thin films with metallic interfacial layers of aluminum and nickel-chromium (Al and Ni-Cr) were grown using a low cost hybrid technique involving a resistive heating thermal evaporator and radio frequency plasma enhanced chemical vapor deposition techniques. Stress, hardness, elastic modulus, bonding, phase, and electrical conductivity of these films were investigated. Introduction of interfacial Al and Ni-Cr layers in DLC led to drastic improvement of its conductivity along with a significant reduction in residual stress but with some reduction of hardness and the elastic modulus. The structural and surface properties of thin films were studied using X-ray diffraction, X-ray photoelectron spectroscopy, and scanning electron microscopy techniques.     

X-ray reflectivity studies on DLC films deposited by microwave ECR CVD: Effect of substrate bias

Diamond like carbon (DLC) films were deposited at room temperature on Si (111) substrates by microwave electron cyclotron resonance (ECR) plasma chemical vapor deposition (CVD) process using plasma of methane diluted with argon gas. During deposition, dc self bias (− 25 V to − 200 V) on substrate was varied by application of RF power to the substrate. The influence of substrate bias on density of the deposited films was studied by X-ray reflectivity (XRR). The results from these measurements are further correlated with the results from UV and visible Raman spectroscopy. DLC film is modeled as a structure having three different layers such as low density surface, bulk and interface with the substrate. This three-layer model is used to fit the measured XRR data to evaluate the surface, interface and interlayer roughness, thickness and density of these films. The surface roughness obtained from XRR is correlated with the results from Atomic Force Microscopy (AFM) measurements. The observed results are explained based on the subplantation model for DLC film growth.     

Characterization and analysis of DLC films with different thickness deposited by RF magnetron PECVD

Diamond-like carbon (DLC) films have excellent mechanical and chemical properties similar to those of crystalline diamond giving them wide applications as protective coatings. So far, a variety of methods are employed to deposit DLC films. In this study, DLC films with different thicknesses were deposited on Si and glass substrates using RF magnetron PECVD method with C4H10 as carbon source. The bonding microstructure, surface morphology and tribological properties at different growing stages of the DLC films were tested. Raman spectra were deconvoluted into D peak at about 1370 cm-1 and G peak around 1590 cm-1, indicating typical features of the DLC films. A linear relationship between the film thickness and the deposition time was found, revealing that the required film thickness may be obtained by the appropriate tune of the deposition time. The concentration of sp3 and sp2 carbon atoms in the DLC films was measured by XPS spectra. As the films grew, the sp3 carbon atoms decreased while sp2 atoms increased. Surface morphology of the DLC films clearly showed that the films were composed of spherical carbon clusters, which tended to congregate as the deposition time increased. The friction coefficient of the films was very low and an increase was also found with the increase of film thickness corresponding to the results of XPS spectra. The scratch test proved that there was good bonding between the DLC films and the substrates.     

Corrosion resistance properties of AZ31 magnesium alloy after Ti ion implantation

Magnesium alloys have a wide range of applications in industry; however, their corrosion resistance, wear resistance, and hardness are rather poor, which limit their applications. Ti ion was implanted into the AZ31 magnesium alloy surface by metal vapor vacuum arc (MEVVA) implanter. This metal arc ion source has a broad beam and high current capabilities. The implantation energy was fixed at 45 keV and the dose was at 9 × 1017 cm?2. Through ion implantation, Ti ion implantation layer with approximately 900 nm in thickness was directly formed on the surface of AZ31 magnesium alloy, by which its surface property greatly improved. The chemical states of some typical elements of the ion implantation layer were analyzed by means of X-ray photoelectron spectroscopy (XPS), while the cross sectional morphology of the ion im-plantation layer and the phase structure were observed by means of scanning electron microscopy (SEM) and X-ray diffraction (XRD). The property of corrosion resistance of the Ti ion implanted layer was studied by the CS300P electrochemistry corrosion workstation in 3.5% NaCl solution. The results showed that the property of corrosion resistance was enhanced remarkably, while the corrosion velocity was obviously slowed down.     

钽掺杂对多层Ta-DLC薄膜摩擦及腐蚀行为的影响

目的 解决316L不锈钢在苛刻海洋环境中易磨损、易腐蚀的问题。方法 采用中频磁控溅射技术在316L不锈钢上沉积了Ta/TaN/TaCN/Ta-DLC薄膜。通过扫描电子显微镜、拉曼光谱、X射线光电子能谱、X射线衍射、纳米压痕、往复摩擦磨损试验和电化学测试等手段,重点研究了DLC膜层中Ta元素掺杂含量对薄膜结构、组成成分、力学性能、摩擦学性能和耐腐蚀性能的影响规律。结果 随着Ta元素含量(原子数分数)从2.04%增到4.16%,薄膜中的sp³键含量呈现先升高后降低的趋势,当Ta原子数分数为3.60%时,薄膜中sp³键含量最高,且薄膜的硬度及弹性模量达到最大,分别为7.01 GPa和157.87 GPa。随着Ta元素含量的增加,薄膜的平均摩擦因数逐渐减小,在4.16%(原子数分数)时达到最小0.21。Ta元素含量对薄膜的结合力影响较小,且所有薄膜结合力总体在10 N左右。当Ta原子数分数为3.60%时,薄膜的腐蚀电流密度及钝化电流密度最小,分别为0.006 μA/cm²和0.63 μA/cm²,比其他薄膜的低1~2个数量级,并且薄膜电阻及电荷转移电阻最大,展现出最为优异的耐腐蚀性能。结论 Ta元素的掺杂提高了薄膜的耐摩擦性能,且适当的Ta元素掺杂能够提高Ta/TaN/TaCN/Ta-DLC薄膜的耐磨耐蚀性能。     

硬质合金刀具上的类金刚石薄膜硬度的研究

采用射频辉光等离子体法制备了类金刚石薄膜,研究了影响类金刚石薄膜硬度的各种因素,包括:极板间距、甲烷浓度、射频功率和膜层厚度等,分析了各种生长参数对类金刚石薄膜硬度的影响机理,找出了最佳的生长参数。     

Use of near atmospheric pressure and low pressure techniques to modification DLC film surface

Diamond-like carbon (DLC) films have been use in numerous industrial applications due to its mechanical properties such as low friction coefficient, high hardness, and high adherence on different substrate materials. It has been demonstrated that the DLC surface can be modified with oxygen plasma treatment. The purpose of this paper is to study two kinds of surface treatments (atmospheric and low pressures) using oxygen gas for different etching exposure times in DLC films. Plasma durability along the time was also evaluated. DLC films were deposited using plasma enhanced chemical vapor deposition technique. The properties of DLC treated for both techniques in different exposure times were investigated through Raman, AFM and contact angle measurements. D band position slightly shifts toward lower wave numbers after oxygen plasma etching treatment whilst the surface becomes rougher, although the roughness values are still lower. A conventional wetting contact angle method was used to study the surface properties of DLC films with different treatments. The wetting contact angle reduced significantly due to the increase of carbon–oxygen sites on the surface.     

Duplex diamond-like carbon film fabricated on 2Cr13 martensite stainless steel using inner surface ion implantation and deposition

A duplex plasma immersion ion implantation and deposition (PIIID) process, involving carbon ion implantation and diamond-like carbon (DLC) film deposition, is proposed to treat the inner surface of a tube. Samples of 2Cr13 martensite stainless steel were placed inside the tube to investigate the performance of the films. Carbon ion implantation was finished by biasing the tube with a high voltage, and the DLC film deposition was obtained by biasing the tube with a medium voltage. Raman spectrum, ball-on-disc, indentation and scratch tests were used to investigate the structure, tribological property and adhesion strength of the as-deposited films. The Raman spectrum shows that the sp³ bonding is formed in the as-synthesized film. Tribological and scratch test results reveal that the duplex DLC coating with the implantation time of 1 h has the largest adhesion strength and the best wear resistance.     

Structural and tribological properties of diamond-like nanocomposite thin films

The structural and tribological properties of diamond-like nanocomposite (DLN) thin films, deposited by radio frequency plasma enhanced chemical vapor deposition (rf-PECVD) on the pyrex glass or silicon substrate using the combinations of siloxane and silazane based gas precursors, are discussed. High resolution transmission electron microscopy (HRTEM) result shows the DLN film structure with different nanoparticle size. The surface morphology of the DLN films has been investigated by using atomic force microscopy (AFM). The structural properties of the DLN films are analyzed by Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). We have observed different bonds like C―C, C―H, C―Si, C―O, Si―O, Si―H, etc. in the DLN films by XPS and FTIR analysis, which reveal that it consists of a-C:H and a-Si:O networks. The disorder and graphitic structure of amorphous carbon of the deposited films are analyzed by Raman spectroscopy. The hardness and friction coefficient of the films are measured by nanoindentation and scratch test techniques. Finally, we find that mixed siloxane and silazane precursor (MSSP) based DLN films provide better film-properties like surface roughness, friction coefficient, etc. than those of single siloxane or silazane precursor (SSSP) based DLN films.     

Preparation of H-terminated and aminated diamond like carbon surfaces

H-terminated DLC layers were synthesized on SiO2 substrate by radio frequency (RF) magnetron plasma-enhanced chemical vapor deposition (PECVD) in a conventional reactor using C4H10 as carbon source. As-deposited DLC films were characterized by Raman spectroscopy, scanning electron microscopy (SEM) as well as atomic force microscopy (AFM). The chemical reactivity of the obtained DLC surface was further investigated by exposing the photochemically oxidized DLC surface to a silane reagent. The course of the reaction was followed using water contact angle and X-ray photoelectron spectroscopy.     

COMPARISON OF SURFACE PROPERTIES OF Ti-6Al-4V COATED WITH TITANIUM NITRIDE, TiN+TiC+Ti(C,N)/DLC, TiN/DLC AND TiC/DLC FILMS BY PLASMA-BASED ION IMPLANTATION

1. IlltroductionThe high yield strength and toughness, moderate modules, low density, good corrosionresistance and exceptional biocompatibility of Ti-6Al--4V alloy have made it increasinglypopular in industrial and medical application. But the alloy does not have enough wearresistance, and so is restricted in surface, particularly tribological applications to a certain e.tent[1--2]. It has been demonstrated that plasma-based ion implalltation (PBll), anew cost-effective technique for improvi…     

Ti6Al4V合金上类金刚石膜的摩擦学性能及腐蚀行为

采用离子束沉积技术在医用Ti6Al4V合金表面制备类金刚石薄膜(DLC),利用原子力显微镜、Raman光谱、X射线光电子能谱(XPS)及UMT-2摩擦磨损试验机对薄膜的形貌、结构、摩擦学性能进行表征。采用动电位极化对涂层前后基底的耐腐蚀性能进行测试。结果表明:制备薄膜为类金刚石碳结构,基底偏压对薄膜形貌、结构有较大影响;偏压为-100V时制备的薄膜表面粗糙度低(6.5nm),sp3/sp2比值高,摩擦学性能优异;经DLC膜保护的合金基底耐腐蚀性能获得明显改善。     

Effect of ion implantation layer on adhesion of DLC film by plasma-based ion implantation and deposition

High adhesive diamond-like carbon (DLC) film on SUS304 was obtained using carbon ion implantation between DLC film and substrate material by plasma-based ion implantation and deposition (PBIID). Implantation of mixed silicon and carbon ions to the substrate resulted in much higher adhesion strength than that of the epoxy resin. Effect of ion implantation on adhesion of DLC film was studied by cross sectional STEM observation and EDS element analysis. Enhancement in adhesive strength by ion implantation of mixed carbon and silicon was ascribed to the formation of the multilayer interface consisting of mixed carbon and silicon ion implanted layer and the amorphous layer of carbon and silicon.     

Structure, scratch resistance and corrosion performance of nickel doped diamond-like carbon thin films

Nickel doped diamond-like carbon (DLC:Ni) thin films were fabricated on conductive p-Si (100) substrates with DC magnetron sputtering deposition by varying DC power applied to a Ni target. The bonding structure, surface morphology, scratch resistance and corrosion resistance of the DLC:Ni films were studied using X-ray photoelectron spectroscopy (XPS), micro-Raman spectroscopy, atomic force microscopy (AFM), micro-scratch test, potentiodynamic polarization test and open circuit potential measurement. The results indicated that the corrosion resistance of the DLC:Ni films in a 0.6 M NaCl solution decreased with increased Ni content in the films though the films showed good passivation behavior in the NaCl solution.