不同钢种离子渗硫层的抗擦伤性能研究

为改善高速钢，模具钢和45钢的抗擦伤性能，采用低温离子渗硫技术在这三种材料表面生成了FeS固体润滑渗硫层，在QP-100球盘式摩擦磨损试验机上对比研究了这三种材料渗硫层在油润滑条件下的抗擦伤及摩擦学性能。利用SEM与XRD观察分析了渗硫层截面，擦伤面形貌及表面相结构，利用AES及XPS分析了擦伤表面元素沿深度的分布及边界润滑膜化合物的价态，研究表明，渗硫后三种材料的抗擦伤及摩擦学性能都有明显改善，其中渗硫高速钢的抗擦伤性最好。其后依次为渗硫模具钢，渗硫45钢，分析认为，不同钢种渗硫层抗擦伤性能的差异主要由基体硬度，组织结构及耐蚀性三方面决定。     

低温离子渗硫层的结构和减摩性能

采用低温离子渗硫技术在４５和ＧＣｒ１５钢表面形成一定厚度的渗硫层。采用金相,ＳＥＭ＋ＥＤＸ,ＸＲＤ等方法分析了渗层结构。采用ＳＲＶ往复式磨损试验机。在液体石蜡润滑条件下对渗层的摩擦学性能进行了研究。     

离子硫化层与热喷涂硫化层的摩擦学性能比较

分别采用低温离子渗硫和等离子喷涂的方法在45^#钢表面制备了硫化层。在摩擦磨损试验机上对比研究了这两种硫化层在油润滑条件下的摩擦学性能。利用XRD分析了硫化层的相结构，用SEM观察了硫化层的表面及磨面形貌并进行了能谱分析。结果表明，各硫化层的摩擦学性能明显优于原始基体表面，其中离子硫化层的减摩性和耐磨性更好，耐热喷涂硫化层的抗擦伤性更佳。造成这种差别的主要原因在于两种硫化层的成膜机理不同。     

Boriding of nickel in a fluidized bed reactor

Heat treatments of alloys in fluidized bed reactors have been carried out for more than 25 years. Recently, this technology has been used for surface engineering applications in the deposition of hard and/or corrosion resistant layers. In the present paper we used FBT to deposit boride coatings on nickel metal. The coatings were examined by means of optical microscopy, X-rays diffraction and Vickers microhardness in terms of the coating’s morphology, thickness, hardness and phase formation. The coating’s tribological properties were evaluated under dry wear. The as-produced coatings are characterized by good uniformity and it was found that only Ni₃B (space group Pnma) was formed during the treatment. Furthermore, the boride layer improved the tribological properties of nickel.     

金属等离子体浸没离子注入改善9Cr18轴承钢表面耐磨性的研究

采用新改进的阴极弧金属等离子体源 ,对 9Cr18轴承钢进行了金属等离子体浸没离子注入 (PIII)处理。首先将Ti,Mo和W离子分别注入到 9Cr18钢的表面 ,然后再对其进行N等离子体浸没离子注入 ,从而在 9Cr18钢表面形成了一层超硬耐磨的改性层。对PIII处理后的试样进行了显微硬度和磨损特性测试 ,结果表明 ,经PIII处理后的试样表面的显微硬度和耐磨性显著提高 ,而其中经Ti和Mo注入再进行N离子注入的试样效果更为明显。与仅进行N离子注入的试样相比 ,金属加N离子注入的试样表面耐磨性提高幅度更大 ,表明金属PIII在改善 9Cr18钢表面性能方面具有广阔的应用前景。XPS分析结果表明 ,PIII处理后试样表面形成了超硬的氮化物相 ,它们在改善材料表面特性中起到了重要的作用。     

Maßgeschneiderte Tribologie durch Laseroberflächenbehandlung

Tailored tribology by laser surface treatment There are quite different requirements for tribological properties of surfaces in industry. Both reduction and maximization of friction and/or wear are possible requirements. The friction and wear properties depend on the tribological system consisting of the friction partners, the medium between them and the environment around them. So for each application tailored surfaces with special tribological properties are needed. In the paper examples are presented which deal with the investigation and the implementation of laser based processes to obtain surfaces with very different tribological properties. Wavelengths, output power values, intensity distributions and beam qualities of the available lasers vary in a wide range. Also the available devices for beam formation and beam guidance enable special processes for tailoring properties for particular applications. These processes are for example the single‐layered or multi‐layered laser cladding generating homogeneous or graded claddings, the laser alloying or laser dispersing and the laser stimulated deposition of diamond layers at atmospheric pressure.     

Tribological properties of sulfurized-nitrided layer prepared by a two-step method

The tribological properties of nitrided layer and sulfurized-nitrided layer of AISI 4135 steel were investigated under oil lubrication, and the layers were prepared by the ion nitriding treatment and a two-step method as the ion nitriding plus sulfurizing duplex treatment, respectively. A ball-on-disc friction and wear tester was adopted to evaluate the tribological performance. Scanning electron microscope (SEM), scanning Auger microprobe (SAM) and X-ray photoelectron spectroscope (XPS) were used to identify the morphologies and chemical compositions of the treated layer and the worn surface. It was presented that the sulfurized-nitrided sample with a thin FeS layer possessed much better tribological behaviors than the nitrided sample, including load carrying capacity, wear resistance, friction reduction and duration time. The mechanism was supposed that the decomposed activated S atoms of FeS layer promoted a new FeS chemical reaction film formation, which induced to the thin FeS layer playing as a solid lubricant for a longer time.     

氧化程度对氧化石墨改性环氧树脂涂层摩擦学性能的影响

通过改变H2SO4／KMnO4氧化体系,制备出几种不同氧化程度的氧化石墨,分别对环氧树脂涂层进行填充耐磨改性。通过红外光谱和扫描电镜分析、电性能测试及摩擦磨损性能试验,研究硫酸用量、氧化石墨电阻与氧化程度三者之间的关系,考察氧化程度对氧化石墨结构及其填充改性环氧树脂耐磨涂层摩擦学性能的影响。结果表明：硫酸用量的增加引起氧化石墨电阻和氧化程度非线性增大,同时氧化石墨层状结构剥离成氧化石墨片的程度增加。氧化程度在95％以上的氧化石墨已失去固体润滑特性,导致填充改性环氧涂层摩擦性能下降,磨损增加,氧化程度约85％的氧化石墨填充改性涂层的综合性能最佳。     

Hardness and tribology measurements on ZrN coatings deposited by reactive sputtering technique

ZrN coatings have been grown in an rf sputtering deposition chamber, using different ratios of Ar/N₂ (5/1, 5/5, 1/5) in the reactive gas flow. After deposition, the coatings were thermally treated in a 500 °C oxygen atmosphere, in order to test the thermal stability of the layers or the oxynitride formation. The chemical composition, surface roughness and structural, mechanical and tribological properties of the as-deposited and annealed samples have been measured by energy dispersive spectroscopy (EDS), atomic force microscopy (AFM), X-ray diffractometry, nanoindentation and pin-on-disk techniques, respectively. Deposition parameters determine the growth rate, crystalline structure and surface roughness, which affect the mechanical and tribological behaviour of the samples. The best mechanical and tribological performance and highest growth rate was found for the sample grown under 5 sccm Ar+1 sccm N₂ gas flow. The as-deposited layers have a low wear, showing an increase in hardness after annealing making them suitable as protective layers.     

含硫镍基合金与YJ2硬质合金对偶的高温摩擦特征分析

本文研究了通过热压法制备得到的含硫镍基合金与YJ2硬质合金对偶的摩擦特征。结果表明：在高温摩擦过程中，材料中的硫化物共晶体是主要的润滑组元，摩擦面的温度对其润滑效果有较大的影响；材料与YJ2对偶时的摩擦系数随着温度变化有所不同，但是磨损率都随着温度升高而增大，其高温下磨损形式主要为磨粒磨损和氧化磨损；YJ2硬质合金表面生成的氧化物对材料减摩性能有很大影响。     

Anisotropic tribological properties of the coating on a magnetic recording disk

Mechanical and analytical tools were used to characterize the coatings on a magnetic recording disk. The mechanical and tribological properties of the coating were evaluated using the nano-indentation and nano-scratch tests. The transmission electron microscopy (TEM) and the Auger electron spectroscopy (AES) were used to determine the thickness and elemental compositions of the coating layers, while the atomic force microscopy (AFM) was used to study the surface topology and roughness. It was shown that the disk surface had a texture preferentially oriented along the circumferential direction with fairly uniform summit height and little waviness. The variations of surface roughness data were analyzed statistically, based on the Gaussian probability and Weibull cumulative probability theories. The coefficient of friction and the surface roughness were found to depend on scan direction relative to the coating texture. The hardness and elastic modulus were strongly influenced by the coating/substrate interaction and the surface roughness of the coating.     

渗氮与Ni—Cu—P刷镀复合处理表面的摩擦学性能

利用球一盘摩擦磨损试验机研究了办界润油条件下４５＾＃钢渗氮表面刷镀Ｎｉ－Ｃｕ－Ｐ镀层的摩擦学性能,结果表明,在硬度较高且具热硬性的渗氮层上刷镀较软的Ｎｉ－Ｃｕ－Ｐ镀层,可较４５＾＃钢直接刷镀Ｎｉ－Ｃｕ－Ｐ镀层及未刷镀的渗氮层,摩擦学性能全面显著提高,还利用扫;描电子显微镜和铁谱仪对磨损表面的成分、形貌和磨屑形态进行了分析。     

Pulse current co-deposition of Ni-WS2 nano-composite film for solid lubrication

This study was undertaken to observe the effect of nano-composite coating on steel surface for enhancing its tribological properties. In the investigation, EN31 steel surfaces were coated with nano-composite (Ni-WS₂) by pulse current co-deposition process in order to improve the tribological properties of the surface. The coatings were prepared according to different parameter settings. The effect of variations on coating thickness, microstructure, surface morphology, microhardness and tribological properties was observed. The maximum coating thickness of 117?µm with 8% by weight of WS₂ particle concentration could be attained with the following parameter settings: applied voltage: 5?V; pulse frequency: 20?Hz; WS₂ concentration: 20?g/l; duty factor: 0.6 and bath temperature: 50°C. The average friction coefficient of the deposited surface was 0.11, which is significantly less than that of the EN31 steel surface (average coefficient of friction >?0.5).     

Effect of Oxidation Conditions on the Phase Composition, Structure, and Properties of Photosensitive Lead Sulfide Layers

The oxidation of single-crystal and polycrystalline lead sulfide was studied as a function of process duration and temperature. The phase changes during oxidation were followed by thermal analysis, x-ray diffraction, and x-ray photoelectron spectroscopy. The transport properties of as-grown and oxidized PbS layers were measured. A mechanism was proposed for the bulk and surface processes resulting in the formation of photosensitive PbS-based structures.     

Mechanical and tribological properties of gradient a-C:H/Ti coatings

The unusual combination of high hardness and very low friction coefficient are the most attractive tribological parameters of DLC (diamond-like carbon) layers. However, their usability is strongly restricted by the limited thickness due to high residual stress. The main goal of the presented work was to obtain thick, wear resistant and well adherent DLC layers while keeping their perfect friction parameters. As a proposed solution a Ti-Ti _x C _y gradient layer was manufactured as the adhesion improving interlayer followed by a thick diamond-like carbon film. This kind of combination seems to be very promising for many applications, where dry friction conditions for highly loaded elements can be observed. Both layers were obtained in one process using a hybrid deposition system combining PVD and CVD techniques in one reaction chamber. The investigation was performed on nitrided samples made from X53CrMnNiN21-9 valve steel. Structural features, surface topography, tribological and mechanical properties of manufactured layers were evaluated. The results of the investigation confirmed that the presented deposition technique makes it possible to manufacture thick and well adherent carbon layers with high hardness and very good tribological parameters. Preliminary investigation results prove the possibility of application of presented technology in automotive industry.     

Nanotribology and nanomechanics in nano/biotechnology

Owing to larger surface area in micro/nanoelectromechanical systems (MEMS/NEMS), surface forces such as adhesion, friction, and meniscus and viscous drag forces become large when compared with inertial and electromagnetic forces. There is a need to develop lubricants and identify lubrication methods that are suitable for MEMS/NEMS. For BioMEMS/BioNEMS, adhesion between biological molecular layers and the substrate, and friction and wear of biological layers may be important, and methods to enhance adhesion between biomolecules and the device surface need to be developed. There is a need for development of a fundamental understanding of adhesion, friction/stiction, wear, the role of surface contamination and environment, and lubrication. MEMS/NEMS materials need to exhibit good mechanical and tribological properties on the micro/nanoscale. Most mechanical properties are known to be scale dependent. Therefore, the properties of nanoscale structures need to be measured. Component-level studies are required to provide a better understanding of the tribological phenomena occurring in MEMS/NEMS. The emergence of micro/nanotribology and atomic force microscopy-based techniques has provided researchers with a viable approach to address these problems. This paper presents an overview of micro/nanoscale adhesion, friction, and wear studies of materials and lubrication studies for MEMS/NEMS and BioMEMS/BioNEMS. It also presents a review of scale-dependent mechanical properties, and stress and deformation analysis of nanostructures.     

Ｔi６A14V等离子体浸没式离子注入

采用新型等离入体浸没式离子注入技术,对Ｔi6A14V合金进行氮离子注入,对注入层的成分,组织和性能的分析表明,注入层中氮浓度的分布具有类高斯分布特征,在注入层中有ＴiN和非态相形态,注入层的显微硬度和摩擦性能得到明显改善。     

Impact of post-curing duration on mechanical,thermal and tribological behavior of an organic friction material

This paper aimed to study the influence of post curing duration on mechanical, thermal and tribological behavior of friction materials elaborated with simplified formulation. Surface mechanical properties and thermal conductivity were analyzed and tribological behavior was studied for various thermal severities of sliding conditions. Results indicated that post curing for long duration allowed to reduce thermal conductivity and to homogenize the surface mechanical properties of the friction material. Concerning tribological behavior, it was shown that a longer post curing duration permitted to reduce the level of friction and to increase wear resistance. Worn surface morphology investigation using SEM revealed that wear and friction mechanisms involved in the contact were sensitive to post curing duration.     

Surface sulfurization studies of thin film Cu(InGa)Se2 solar cells

Sulfurization of copper indium gallium diselenide (CIGS) thin films solar cell absorber has been attempted to enhance the open circuit voltage of the device by increasing the band gap of the absorber near the interface. The homogeneous co-evaporated Cu(InGa)Se₂ thin film was used for sulfurization. The sulfurization was studied in hydrogen sulfide and mixture of hydrogen sulfide and hydrogen selenide gases with the inclusion of oxygen. The structural and compositional properties of the absorber layers were investigated by XRD, EDS and AES analysis. The device results were characterized using current-voltage (I-V) and quantum efficiency. Sulfurization in hydrogen sulfide gas forms a fully converted sulfide layer at the top of the absorber layer, which in turn forms a barrier for the current collection; the device results also support this observation. Sulfurization in mixture of hydrogen sulfide and hydrogen selenide gases forms a wide band gap Cu(InGa)(SeS)₂ layer at the surface by partial replacement of Se by S. The device does not show an increase in open circuit voltage. This may be attributed to the diffusion of Ga away from the surface with the inclusion of sulfur at the surface, which counters the beneficial effect of sulfur at the surface.     

铈掺杂白云母复合粉体的制备及其减摩抗磨机理

采用机械力固相化学反应法制备了稀土铈掺杂白云母(Muscovite,MC)的复合粉体(Ce-MC),表征了粉体的微观形貌、晶体结构、元素组成和粒径分布。利用四球摩擦磨损试验机考察比较了MC和Ce-MC作为润滑脂添加剂的摩擦学性能,对磨损表面进行了SEM、EDS和XPS分析,并探讨了Ce-MC的减摩抗磨机理。结果表明:CeMC复合粉体中铈化合物包覆在白云母粉体表面,主要物相为CeO_2;Ce-MC和MC作为添加剂均能提高锂基润滑脂的减摩抗磨性能,且Ce-MC复合粉体的摩擦学性能优于MC单体;Ce-MC优良的摩擦学性能与其磨损表面Ce-MC的物理吸附膜和主要成分为Fe_2O_3、SiO_2的化学反应膜有关。