TiN/TiC multilayer films deposited by pulse biased arc ion plating

TiN/TiC multilayer films were deposited on high-speed-steel (HSS) substrates using pulse biased arc ion plating. For comparison, TiN and TiC films were also deposited. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and Auger electron spectroscopy (AES) were applied to investigate the modulation period thickness, microstructure and content depth distribution of the films, respectively. And microhardness and film/substrate adhesion were also analyzed using knoop tester and scratching method. The results showed that the multilayer films with different modulation period of 40-240 nm exhibit a modulation structure and the interface width is about 20∼30 nm. Microhardness of the multilayer films were not obviously improved compared to that of TiN and TiC film, and the reason was analyzed. In comparison to TiN film, film/substrate adhesion values of the multilayer films were deteriorated with the increasing of modulation period due to the brittle characteristics of TiC film.     

铀表面等离子体浸没离子注入沉积制备氮化层+Ti/TiN多层膜的结构与性能

为了改善金属铀的摩擦磨损和抗腐蚀性能,采用等离子体浸没离子注入沉积(PIII&D)技术在铀表面氮化,再沉积Ti/TiN多层膜.利用扫描电镜和X射线衍射分析了薄膜的形貌和组织结构;对薄膜的摩擦磨损和抗湿热腐蚀性能进行了测试.结果表明:薄膜表面致密,界面晶粒柱状生长方式被阻断,晶粒细化;薄膜为Ti和TiN的双相结构,衍射谱中出现了UO_2和U_2N_3的衍射峰;薄膜大大提高了铀基体的摩擦磨损和抗湿热腐蚀性能,调制周期对薄膜性能的影响较大.     

Raman spectroscopy and mechanical properties of multilayer tetrahedral amorphous carbon films

In order to take the tetrahedral amorphous carbon (ta-C) films as the high acoustic impedence layer in a Bragg reflector isolating acoustic wave from the substrate in solidly mounted resonator, the multilayer films consisting of sp2-rich layers and sp3-rich layers were deposited from a filtered cathodic vacuum arc by adjusting the substrate bias. The microstructure of the films was evaluated using a visible Raman spectroscopy. The stress was calculated according to the changed curvature of the coated and bare substrate. The hardness, modulus and scratching were measured using a nanoindenter. It has been shown that the multilayer structure maintaining high tetrahedral content, high hardness and high elastic modulus is still characterized with lower intrinsic stress and better adhesion.     

Cu丝上沉积Ti/TiN多层膜的研究

铜丝可用于尿毒症患者腹膜透析置管术中的替代导丝。为了减少或消除铜离子对生物组织的损害,增加铜丝表面的生物相容性,同时又保持铜丝较好的塑性变形能力,本文采用电弧离子镀工艺在铜丝上沉积Ti/TiN多层膜。研究结果显示,镀膜铜丝表面光亮呈金黄色。沉积膜有明显的周期性层状特征,TiN相和金属Ti相周期性交替分布。其中,TiN相具有(111)晶面择优取向。沉积膜与铜丝结合良好,弯曲时镀膜铜丝没有出现微裂纹和膜脱落现象。室温消毒液浸泡和高温蒸汽消毒处理后,镀膜铜丝表面没有变化。腹膜透析置管术中使用镀膜铜丝,患者腹膜炎发生率明显降低,镀制Ti/TiN多层膜的铜丝适合应用于腹膜透析手术。     

Theoretical explanation of Ag/Cu and Cu/Ni nanoscale multilayers softening

Relationship between metallic multilayers hardness and monolayer thickness has been investigated and explained for electroplated Ag/Cu and Cu/Ni multilayers using a modified Thomas-Fermi-Dirac electron theory. Experiments reveal that the peak hardness of Ag/Cu multilayers occurs at the monolayer thickness of about 25 nm, while the peak hardness of Cu/Ni multilayers occurs at about 50 nm. Critical monolayer thickness corresponding to the peak hardness is approximated by the grain size limit of stable dislocations in Ag crystals for the Ag/Cu multilayers and in Cu crystals for Cu/Ni multilayers. Grains size limits are calculated based on a modified Thomas-Fermi-Dirac electron theory. Developed relationship between the critical monolayer thickness and the grains size limit helps understand nanoscale metallic multilayers softening.     

基于SVR的脉冲激光沉积TiN/AlN多层薄膜的工艺优化

根据脉冲激光沉积(PLD)法在单晶Si试样表面沉积制备多层TiN/AlN硬质膜实验数据,应用基于粒子群算法(PSO)寻优的支持向量回归(SVR)方法,建立不同工艺参数下沉积的TiN/AlN多层膜的AlN膜厚及TiN薄膜硬度的SVR预测模型。在相同的训练与测试样本集下,将SVR所得的AlN膜厚预测值与免疫径向基函数(IRBF)神经网络的计算结果进行比较。结果表明,SVR模型训练和预测结果的平均绝对百分误差要比IRBFNN模型的小,其预测精度更高,预测效果更好。应用SVR的TiN薄膜硬度模型对PLD法沉积TiN薄膜的工艺参数进行了优化,分析了多因素对PLD法沉积TiN薄膜硬度的交互作用和影响。该方法可为人们利用PLD法沉积TiN/AlN多层功能薄膜提供科学的理论指导,具有重要的理论意义和实用价值。     

磁控溅射Fe-N薄膜及Fe-N/TiN多层膜的结构和磁性

用磁控溅射法制备了Fe N薄膜和Fe N/TiN多层膜。结果表明 ,在常温下 ,使用较小的氮、氩比溅射 ,生成的Fe N薄膜主要是含氮α Fe固溶体 ,并且N原子进入α Fe晶格是饱和磁化强度提高的一个原因。Fe N/TiN多层膜的层间耦合作用以及减小每一Fe N层厚度而引起的晶粒尺寸的减小可以有效地降低薄膜的矫顽力 ,从而获得更好的软磁性能     

不同微结构Ti/TiN多层涂层的抗冲蚀性能研究

采用离子源辅助的真空多弧镀膜机在TC11基体上制备了不同层间结构的多层结构TiN/Ti涂层。研究了各涂层的微结构对涂层力学性能和抗冲蚀行为影响。研究发现与基体相比制备涂层后的试样冲蚀磨损率明显降低,最大降幅可达90%。不同微结构的TiN/Ti多层结构涂层的破坏形式与Ti金属层与TiN层分布有非常密切的联系,TiN较厚时整体硬度较高,涂层抵抗冲击破坏的能力强,裂纹不容易产生.经过冲刷试验后普遍呈现梯田型的冲刷痕迹,从冲刷坑中心部位向边缘部位延伸,涂层逐层脱落而造成冲蚀流失,没有出现整体脱落的情况。     

Low friction CrN/TiN multilayer coatings prepared by a hybrid high power impulse magnetron sputtering/DC magnetron sputtering deposition technique

High power impulse magnetron sputtering (HIPIMS) has gained increasing scientific and industrial attention as it allows high plasma densities without the drawback of droplet formation. Recently, we showed that by a combination of HIPIMS with dc magnetron sputtering the properties of the coatings are comparable to those prepared solely with HIPIMS, but with the advantage of increased deposition rate.Here, we show that for CrN_HIPIMS/TiN_DCMS multilayered coatings the friction coefficient µ decreases from 0.7 to 0.35 (with an almost constant hardness H around 25 GPa, and modulus of indentation around 375 GPa) when decreasing the bilayer period λ from 7.8 to 6.4 nm, while keeping the CrN_HIPIMS layer thickness constant at 3.2 nm. A further reduction of the friction coefficient at room temperature dry-sliding testing to ∼ 0.25 or 0.05 is obtained when an additional HIPIMS cathode equipped with a Cr or Ti target material, respectively, is added to the process. Contact angle measurements of distilled water drops on as deposited film surfaces were carried out to investigate their wettability. The measurements show, that with increasing contact angle from 70° to 90°, for the individual coatings prepared, also their friction coefficient increases from ∼ 0.05 to ∼ 0.8. The depositions of all coatings were achieved with two- and threefold substrate rotation, which meet the industrial requirements of uniform deposition on complex shaped specimens.     

Comparison of microstructure and phase transformation for nanolayered CrN/AlN and TiN/AlN coatings at elevated temperatures in air environment

CrN/AlN and TiN/AlN multilayer coatings with modulation period of 4 nm and thickness ratio equal to 1.0 were manufactured by RF magnetron sputtering. Both films were annealed at temperatures of 800 °C in air for 1 h and then for an additional 9 h. Both coatings in as-deposited and after heat treatment were evaluated with a transmission electron microscope (TEM) equipped with EDS. After heat treatment at 800 °C for 1 h, a thick oxide layer around 260 nm was formed on the surface of the TiN/AlN coating. The oxide layer which formed on the coating was composed of three different regimes, including Al-enriched oxide with excess oxygen on the top surface, a crystalline Al-depleted TiO₂ layer 30-80 nm thick above the nitride coating and in between, mixed nano-crystalline Al₂O₃ and TiO₂ films. In comparison, only one oxide layer smaller than 50 nm in thickness was found in the annealed CrN/AlN coating. This amorphous or nanocrystalline oxide layer identified by EDS was a metal-deficient oxide, in which Al₂O₃ and Cr₂O₃ were mixed together forming a solid solution. As a result, the CrN/AlN coating exhibited superior stability compared to the TiN/AlN coating at elevated temperatures.     

TiN/Ti多层膜调制比对摩擦磨损行为影响的研究

考察了TiN/Ti多层膜调制比对其摩擦磨损行为的影响. 采用磁过滤阴极弧沉积的方法制备了具有不同调制比的TiN/Ti多层膜, 用扫描电镜和透射电镜对其层状结构及子层结构进行了观察和分析. 用纳米压痕和SRV摩擦磨损试验的方法, 对多层膜进行了纳米硬度和弹性模量测试以及摩擦磨损实验. 结果表明, 所制备的TiN/Ti多层膜层状结构清晰, 与基底结合良好, 调制比对多层膜的硬度和磨损特性影响较大, 而对摩擦系数的影响却不明显. 结合实验结果, 讨论了硬度与弹性模量的比值(H/E值)对TiN/Ti多层膜耐磨性的影响.     

A study of photoconductive properties of vacuum-sublimated copper-phthalocyanine/zinc sulphide multilayer films

Copper-phthalocyanine (CuPc)/zinc sulphide (ZnS) multilayer films were prepared by vacuum-sublimation. X-ray diffraction, optical absorption spectra and photoconductive properties were measured for the multilayer films. The results showed that the photoconductive properties of the CuPc/ZnS multilayer films were better than that of the CuPc film. The effects of the pair number on the photoconductive properties of the multilayer films were studied. It was found that three-pair CuPc/ZnS multilayer film had the best photoconductive properties with the light sensitivity S=100 lx s and residual potential V_R=17 V.     

Structural design of Cr/GLC films for high tribological performance in artificial seawater: Cr/GLC ratio and multilayer structure

In this paper,graphite-like carbon(GLC)films with Cr buffer layer were fabricated by DC magnetron sputtering technique with the thickness ratio of Cr to GLC films varying from 1:2 to 1:20.The effect of Cr/GLC modulation ratio on microstructure,mechanical and tribological properties in artificial seawater was mainly investigated by scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS),nano-indenter and a reciprocating sliding tribo-meter.The propagation of defects plays an important role in the evolution of delamination,which is critical to wear failure of GLC films in artificial seawater.Designing the proper multilayer structure could inhibit the defects propagation and thus protect the basis material.The multilayer Cr/GLC film with optimized ratio of 1:3 demonstrates a low average friction coefficient of 0.08±0.006 and wear rate of(2.3±0.3)×10~(-8)mm~3/(N m)in artificial seawater,respectively.     

AlN/WAlN/W太阳能选择性吸收多层薄膜研究

采用全封闭磁场的非平衡态磁控溅射系统,以纯金属为靶材,制备了AlN/WAlN(多层)/W薄膜。X射线掠射(GID)、扫描电镜(SEM)以及分光光度计等测试手段分析薄膜的相结构、表面形貌以及吸收光谱等特性。结果表明,薄膜沉积设备性能稳定,W、Al靶材溅射率高。获得AlN/WAlN(多层)/W薄膜中各层薄膜表面质地都较均匀,且为多晶态或纳米晶薄膜。该结构膜系对波长在200～2000nm范围内的光波有较高的吸收效果,平均吸收率可达96%以上,吸收性能优异。     

等离子喷涂工艺对钽/钨复合涂层组织结构的影响

采用等离子喷涂方法制备了Ta/W复合涂层,研究了喷涂距离和喷涂功率对Ta/W涂层密度、沉积效率、化学成分和组织结构的影响.结果表明,Ta/W涂层组织致密,钽、钨涂层之间没有明显的界面,涂层密度分别达到14.27 g/mm3和16.86 g/mm3;喷涂功率对钨粉的沉积效率影响较大,喷涂功率低于40 kW以下时钨粉的沉积效率极低;涂层中的氧含量较低,氧化主要发生在熔融粒子飞行过程中,采用惰性气体保护可以减少涂层中的氧含量.     

脉冲偏压幅值对TiN／TiAlN多层薄膜微观结构和性能的影响

采用电弧离子镀的方法,通过改变脉冲偏压幅值在M2高速钢表面制备了TiN／TiAlN多层薄膜,研究了脉冲电压幅值TiN／TiAlN多层薄膜微观结构和性能的变化。随着脉冲偏压幅值的增加,薄膜表面的大颗粒数目明显减少。EDX结果表明,脉冲偏压幅值的增加还引起Al／Ti原子比的降低。TiN／TiAlN多层薄膜主要以（111）晶...     

Effect of isotropic interlayers on the mechanical and thermal properties of carbon/carbon composites

Multilayer which consists of isotropic (ISO) interlayer and rough laminar (RL) and single RL structure carbon/carbon (C/C) composites have been prepared by isothermal chemical vapor infiltration at 5 and 1 kPa. Mechanical and thermal properties of both composites have also been studied. Experimental results indicate that ISO interlayer between fiber and matrix plays an important role on fracture behavior and strength of the composites. Comparing with single RL structure composites, the strength decrease of composites with ISO interlayers is about 28-40%. ISO interlayer is the main source of fracture due to its low density and micropores between crystallites. The low thermal conductivity of ISO interlayers also results in the thermal property degradation of obtained C/C composites. By reducing infiltration pressure, the ISO interlayers are substituted by compact RL matrix which improves the general properties of C/C composites.     

Microstructure and tribological properties of in situ synthesized TiN/Ti3Al intermetallic matrix composite coatings on titanium by laser cladding and laser nitriding

TiN reinforced Ti₃Al intermetallic matrix composite (TiN/Ti₃Al IMC) coatings were in situ synthesized on a pure Ti substrate with Ti + Al mixed powders in nitrogen atmosphere by laser cladding and laser nitriding. It was found that the growth morphologies of the TiN reinforced phase in the TiN/Ti₃Al IMC coatings were granular-like, flake-like, and undeveloped dendrites at lower N₂ flow rate; and granular-like, undeveloped and developed dendrites at higher N₂ flow rate. In addition, the volume fraction of the TiN phase increased with increasing nitrogen flow rate. The hardness of the TiN/Ti₃Al IMC coatings was higher than that of the Ti₃Al coating, which increased with increasing volume fraction of the TiN phase. Friction and wear tests revealed that the wear resistance of TiN/Ti₃Al IMC coatings was superior to those of pure Ti and Ti₃Al coating. It is well worth noting that the TiN/Ti₃Al IMC coatings showed excellent wear resistance under lower normal loads.     

多弧离子镀与磁控溅射共沉积TiN/TiCN多层膜的高温抗氧化性能

TiN/TiCN多层膜的高温抗氧化性研究对于扩大其应用领域具有重要作用,但目前鲜见相关报道。采用多弧离子镀与磁控溅射技术以不同调制周期在304不锈钢表面共沉积TiN/TiCN多层膜。采用XRD、XPS、倒置显微镜及高温氧化试验研究了多层膜的高温抗氧化行为。结果表明:TiN/TiCN多层膜表面光滑平整、均匀致密,薄膜主要为具有Ti-(C,N)键的fcc-TiN结构;随着调制周期的减小,TiN/TiCN多层膜生长取向发生转变,且具有(111)晶面生长织构;随着氧化温度的升高,多层膜的显微硬度逐渐降低,氧化增重速率不断增大,且在700℃之后变化速率较快,薄膜的开始氧化温度约为750℃;随着调制周期的减小,多层膜TiN与TiCN界面层数量增多,促使晶粒细化,提高了其致密性,还隔断了缺陷贯穿薄膜的连续性,显著降低了薄膜的孔隙率,致使O原子扩散困难,增强了薄膜的高温抗氧化性能。