磁控溅射银/铜双层膜的电性能和结合强度

采用磁控溅射工艺在微波腔体耦合器内壁沉积了银/铜双层膜,并对该膜的电性能以及膜基结合强度等进行了研究。结果表明:采用磁控溅射法沉积的银/铜双层膜和基体的结合强度可达5.0 MPa;其中,内壁沉积有2μm银/2μm铜双层膜的耦合器的电性能最佳,耦合度为5.75~6.20dB,隔离度为31.02dB,端口驻波值为24.43dB,均达到了电镀的指标,插入损耗小于1.70dB,优于电镀的;该工艺用银量少,无污染,可替代电镀在微波器件表面沉积功能镀层。     

Structure, Mechanical, and Tribological Properties of MoS2/a-C:H Composite Films

A series of hydrogenated amorphous carbon (a-C:H) films doped with molybdenum disulfide (MoS₂) were deposited by medium frequency unbalanced magnetron sputtering with mixed Ar/CH₄ gases of different volume ratios as the source gases. The effects of Ar/CH₄ ratio on morphology, microstructure, mechanical, and tribological properties of the MoS₂/a-C:H composite films were investigated. Results show that the content of MoS₂ in the as-deposited films decreases with the decreasing Ar/CH₄ ratio, and the highest Ar/CH₄ ratio favors the formation of nanostructured films. Besides, the hardness and internal stress of the composite films first decrease and then increase with decreasing Ar/CH₄ ratio. Furthermore, the film deposited at the highest Ar/CH₄ ratio exhibits excellent antiwear ability in all test environments and shows promising potential as a solid lubricating film in aviation and space industries.     

TiNi表面磁控溅射DLC薄膜的纳米压痕与摩擦性能

采用室温磁控溅射技术在TiNi合金表面制备出DLC/SiC(类金刚石/碳化硅)双层薄膜(SiC为中间层),采用拉曼光谱仪、纳米压痕仪和球-盘式摩擦磨损仪研究DLC薄膜的结构、纳米压痕和摩擦性能.结果表明:制备的DLC/SiC薄膜石墨含量高、纳米硬度(5.493 GPa)低、弹性模量(62.2447 GPa)低.在以氮化硅球(半径为2mm)为对摩件,4.9N载荷、室温、Kokubo人体模拟体液润滑下,该DLC/SiC薄膜具有低且稳定的摩擦因数,其平均值约为0.094.     

基体偏压对磁控溅射制备CrAlN薄膜摩擦学性能的影响

通过分析不同基体偏压下磁控溅射(PVD)CrAlN薄膜的结构特征、硬度规律及磨痕形貌,研究基体偏压对CrAlN薄膜的结构、硬度及摩擦磨损性能的影响。借助扫描电子显微镜(SEM)和原子力显微镜(AFM)观察CrAlN薄膜的表面形貌及三维形貌。采用纳米压痕仪对CrAlN薄膜的硬度进行测定。利用球盘式摩擦磨损试验机测定CrAlN薄膜的摩擦系数,并观察薄膜的磨痕形貌,分析薄膜的磨损机理。结果表明:当基体偏压低于150V时,薄膜表面颗粒的平均尺寸随偏压增大而逐渐减小;当基体偏压超过150V时,薄膜表面出现有明显的缺陷。随着基体偏压的增大,薄膜的硬度呈先升高后降低的趋势,并在基体偏压约为150V时达到最大值为27.5GPa;薄膜的摩擦系数呈先减小后增大的趋势,并在基体偏压约为150V时达到最小值0.25;磨痕呈不同程度的犁沟状,在基体偏压为150V时磨痕形貌平整且犁沟最小。当基体偏压为150V时,CrAlN薄膜的表面缺陷最小、硬度最大、摩擦系数低和综合性能最好,薄膜的磨损机理为磨粒磨损。     

类金刚石膜在水环境下的摩擦学行为

测试了 CoCrMo合金表面沉积类金刚石薄膜与CoCrMo在水溶液润滑下的摩擦磨损行为。结果表明：摩擦副在不同浓度牛血清白蛋白溶液润滑下的平均摩擦因数均在0.10左右,CoCrMo合金销磨损量最小值为1.69×10-5 mm3;相同条件下,生理盐水溶液润滑的磨损量为1.38×10-5 mm3,且销表面有转移膜生成;牛血清白蛋白溶液润滑时,界面蛋白吸附层屏蔽了转移膜的形成。根据结果可知,转移膜的形成经历了磨屑附着、连续转移、局部脱落的过程。     

H13钢氮化前后表面磁控溅射CrAlN薄膜的摩擦磨损性能

为了提高H13钢的表面耐磨性能,用直流磁控溅射法在氮化与未氮化的H13钢表面沉积CrAlN薄膜,并对处理前后的摩擦磨损性能进行了比较;用扫描电镜观察薄膜形貌,并测其厚度;测量了随炉硅片的薄膜显微硬度;用摩擦磨损试验机测试了在室温和600℃条件下薄膜的摩擦磨损性能。结果表明：薄膜平均厚度为4．8μm,硬度为23．7GPa;室温条件下材料的表面摩擦因数为0．60～0．65,600℃条件下摩擦因数为0．61～0．96;CrAlN／氮化H13钢和CrAlN／H13钢在室温摩擦时的耐磨性分别是H13钢的1．9倍和1．7倍,在600℃条件下耐磨性分别是H13钢的1．25倍和7倍。     

Tribological behavior of plasma-enhanced CVD a-C:H films. Part I: effect of processing parameters

A systematic study was conducted on the effect of plasma-enhanced CVD processing parameters, namely bias voltage, pressure and CH₄/Ar flow ratio, on the characteristics and tribological response of amorphous hydrogenated carbon (a-C:H) films. Film hardness, intrinsic stress, structure, composition and tribological response were characterized. Variation of processing parameters was found to produce a-C:H films with a range of characteristics with the CH₄/Ar ratio exercising a dominant effect. A low ratio produced harder films with more sp³ bonding, low hydrogen content and low wear rate; whereas a high ratio produced softer films, with more sp² bonding, higher hydrogen content and low friction. Film characteristics were found to affect the wear mechanism with softer films showing a layer-by-layer removal and harder films involving formation of fine debris. These two diverse types of films offer the opportunity to synthesize multilayered films combining desirable properties from each component.     

Tribological Behavior of Nickel-Doped Diamond-Like Carbon Thin Films Prepared on Silicon Substrates via Magnetron Sputtering Deposition

In this study, nickel-doped diamond-like carbon (Ni-DLC) thin films were deposited on silicon (Si) substrates using a magnetron cosputtering system by varying DC power density applied to a Ni target at a fixed DC power density applied to a carbon (C) target. Their tribological properties were systematically investigated using a ball-on-disc microtribometer. The tribological results showed that increasing the DC power density applied to the Ni target more than 0.49 W/cm² significantly increased the friction and wear of the Ni-DLC films due to the degraded sp³-bonded cross-linking structures of the films. However, the much lower friction and wear of the Ni-DLC-coated Si samples than those of the uncoated Si sample implied that the Ni-DLC films could effectively prevent their Si substrates from wear. It could be concluded that the Ni-DLC films could be used as high wear-resistant coatings for micromold applications because their tribological properties were significantly influenced by the DC power density applied to the Ni target.     

不同介质下CrN_X薄膜的摩擦学特性研究

采用电弧离子镀技术在45#钢衬底表面沉积了CrNX薄膜.用显微硬度计测试了薄膜的硬度,用X射线衍射仪分析了薄膜的相结构,用球-盘式摩擦磨损试验机评价了在不同介质条件下(干摩擦、水润滑、油润滑)CrNX薄膜的摩擦学性能,用表面轮廓仪测试了磨痕处的磨痕轮廓,用扫描电镜(SEM)观察了薄膜磨痕形貌.结果表明,相对于干摩擦,水润滑和油润滑条件下,CrNX薄膜的摩擦因数和磨痕深度都有明显降低的趋势.干摩擦条件下薄膜主要表现为磨粒磨损;水润滑条件下,主要表现为腐蚀磨损;油润滑条件下由于油膜在两摩擦表面的吸附,薄膜几乎无磨损.     

热处理条件对溅射法制得的InSb薄膜特性的影响

文中从理论和实验分析了热处理条件对溅射法制得的ＩｎＳｂ薄膜特性的影响。热处理温度、时间和升降温速率都对薄膜特性有影响,通过实验得出了最佳的热处理温度、恒温时间和升降温速率。最后讨论了热处理过程中所采用的３种保护膜。     

Morphological Growth of Sputtered MoS2 Films

Sputtered MoS₂ films from 300 Å to 20,000 Å thick were deposited on metal and glass surfaces. The substrate effects such as surface temperature, finish, pretreatment, and chemistry as they affect the film formation characteristics were investigated by optical, electron transmission, electron diffraction, and scanning electron microscopy. Substrate temperature and surface chemistry were found to be the prime variables as to the formation of a crystalline or amorphous film. The friction characteristics are strictly influenced by the type of film formed. Surface chemistry and surface pretreatment account for compound formation and corresponding grain growth, which directly affect the adhesion characteristics, resulting in poor adherence. The type of surface finish (topography) as related to scratches, impurities, inhomogeneities, etc., are favorable nucleation sites for the growth of isolated and complex nodules within the film, and various complex surface overgrowths on the film. These nodular growth features have progressively more undesirable effects on the film behavior as the film thickness increases.     

Tribological Performance of UHMWPE and PFPE Coated Films on Aluminium Surface

A thin layer of Ultra High Molecular Weight Polyethylene (UHMWPE) or UHMWPE + PFPE is coated onto cylindrical aluminium (Al) pin (4.6 mm diametre) surface with the aim of providing wear resistant coating on this soft and tribologically poor metal. The coefficient of friction and wear life of the coated samples are investigated on a pin-on-disk tribometre under different normal loads (394–622 g) and two sliding speeds (0.1 and 0.31 m/s) against uncoated Al disk as the counterface. Both coatings provide coefficient of friction values in the range of 0.02–0.2 as compared to 0.4–1.0 for uncoated Al. There is tremendous improvement in the wear life of the pin, with UHMWPE + PFPE film giving wear life approximately twice to thrice higher than that with only UHMWPE film. A thin polymer film is transferred to the disk surface during sliding providing very long-term wear life (continuous low coefficient of friction) despite visual removal of the film from the pin surface. The present films will have applications in gears and bearings as solid or boundary lubricants for automotive and aerospace component.     

Tribological Performance of Diamond and Diamondlike Carbon Films at Elevated Temperatures

In this study, the authors investigated the tribological performance of diamond and diamondlike carbon (DLC) films as a function of temperature. Both films were deposited on silicon carbide (SiC) by microwave plasma chemical vapor deposition and ion-beam deposition processes. Tribological tests were performed on a reciprocating wear machine in open air (20 to 30% relative humidity) and under a 10 N load using SiC pins. For the test conditions explored, the steady-state friction coefficients of test pairs without a diamond or DLC film were 0.7 to 0.9 and the average wear rates of pins were 10^?5 to 10^?7 mm³/N·m, depending on ambient temperature. DLC films reduced the steady-slate friction coefficients of the test pairs by factors of three to five and the wear rates of pins by two to three orders of magnitude. Low friction coefficients were also obtained with the diamond films, but wear rates of the counterface pins were high due to the very abrasive nature of these films. The wear of SiC disks coated with either diamond or DLC films was virtually unmeasurable while the wear of uncoated disks was substantial. Test results showed that the DLC films could afford low friction up to about 300° C. At higher temperatures, the DLC films graphitized and were removed from the surface. The diamond films could withstand much higher tempera-lures, but their tribological behavior degraded. Raman spectroscopy and scanning electron microscopy were used to elucidate the friction and wear mechanisms of both films at high temperatures.     

Achieving Low Tribological Moisture Sensitivity by a-C:Si:Al Carbon-based Coating

Owing to the requirements of the stable operation for mechanical components, the urgent challenges are to control tribological moisture sensitivity of protective coatings. In this letter, a-C:Si and a-C:Si:Al carbon-based coatings were successfully fabricated via magnetron sputtering Si, Al, and C. The microstructure, mechanical properties, and tribological moisture sensitivity of as-fabricated carbon-based coatings were comparatively investigated. Results showed that the as-fabricated a-C:Si and a-C:Si:Al coatings were dominated by typical amorphous structure. The co-introduction of Al could effectively relax internal stress and improve adhesive strength as well as maintain the moderately high hardness for the as-fabricated coating. The striking improvement in tribological moisture sensitivity of a-C:Si:Al carbon-based coating was mainly attributed to the superior mechanical properties and the formation of continuously compacted graphitized tribofilm under low relative humidity condition as well as low shear strength colloidal silica tribofilm under high relative humidity condition. The good balance between the hardness and toughness, low internal stress, and superior low tribological moisture sensitivity of a-C:Si:Al coating make it a good candidate for solid lubricating coating in engineering applications.     

Tribological Performance of Alternating-Layered Si-DLC/DLC Films Under Humid Conditions

The tribological behavior of alternating-layered diamond-like carbon (DLC) films was examined under a variety of humid conditions. Alternating deposited layers with Si-incorporated DLC (Si-DLC) and DLC films were prepared using a hybrid coating system. The residual stress of the alternating-layered films was reduced while the hardness was relatively less dependent on the number of alternating-layered sets. A ball-on-disk type tribological test was carried out under the following humid conditions: dry, 50% and 90% relative humidity. The friction coefficient for higher number of alternating-layered sets decreased with increasing humidity conditions but there was no dependency on the wear rate.     

磁控溅射MoS2/Ni复合膜的制备及其摩擦性能

采用磁控溅射法制备了MoS2/Ni复合膜,同时对影响膜层性能的工艺参数进行了初步探讨,并对复合膜进行了成分与结构分析以及摩擦试验.结果表明:在本试验工艺参数(本底真空度为7.0×10-4 Pa,沉积气压为0.5 Pa,溅射功率为160 W,溅射氩气流量为80 cm3/s,靶基距为60 mm,基片温度为70℃)下制备的MoS2/Ni复合膜能够大大降低不锈钢等基底表面的摩擦因数,并且在高速重载的条件下具有更低的摩擦因数和更小的摩擦因数波动值.     

射频磁控溅射WS2 -Ag复合薄膜的组织结构及环境摩擦磨损特性

采用射频磁控溅射方法在高速钢基体上制备WS2-Ag复合薄膜.用能谱(EDS)、X射线衍射(XRD)、扫描电镜(SEM)等对薄膜的成分、组织结构和形貌进行了表征;用划痕仪和球-盘式摩擦仪分别测试薄膜的结合力和大气及真空环境下的摩擦学性能.结果表明,Ag含量为3.23%～5.78%的WS2-Ag复合薄膜具有非晶态结构.Ag的掺入可使WS2薄膜平滑、致密,提高薄膜与基体的结合力,降低薄膜的摩擦因数和摩擦学特性环境敏感性.复合薄膜的耐磨性比纯WS2更加优异,Ag含量5.05%的复合薄膜具有最佳摩擦学性能,其在大气和真空中的磨损率分别为1.06×10-6和0.72×10-6 mm3/(N·m).