电弧增强磁控溅射制备的纳米复合Si-C-N超硬薄膜的结构与性能

耐磨、韧性好的超硬薄膜工程应用价值大。采用电弧增强磁控溅射(AEMS)技术在GCr15轴承钢表面制备了纳米复合Si-C-N超硬薄膜,研究了薄膜的形貌、相组成、硬度、韧性和摩擦磨损性能。结果表明:薄膜中纳米SiC与Si3N4晶体弥散分布于C-C,C=C以及N-C组成的非晶相基体中,形成了纳米晶/非晶复合组织结构,显著提高了薄膜的硬度和韧性,增强了薄膜的抗摩擦磨损性能;薄膜的硬度为(36.5±3.9)GPa,断裂韧性为(4.15±0.28)MPa.m1/2,稳定摩擦系数为0.27左右。     

超高硬度纳米复合薄膜Ti-Si-N结构的研究进展

综述了Ti-Si-N超硬纳米复合薄膜结构形式的研究进展.介绍了研究者对Si原子在Ti-Si-N中形成的晶界是否为晶态的认识与研究,阐述了Si原子在Ti-Si-N中所形成的界面结构形式的研究现状以及Ti-Si-N薄膜沉积过程中的形成机制,并展望了Ti-Si-N超硬纳米复合薄膜今后的研究方向.     

纳米复合超硬薄膜的结构、性能表征

该文分别用直流、脉冲直流和微波等离子体辅助化学气相沉积(PCVD)技术得到了Ti—si—N、Ti—B—N及Ti—Al—si—N纳米复合超硬薄膜,结合微观分析和宏观性能表征,给出了它们的纳米结构特征及其与力学性能的关系,基于工业运用背景,探索了纳米复合薄膜的热稳定性。     

微纳尺度TiN多层薄膜/涂层力学性能研究进展

TiN纳米多层薄膜/涂层由于其高的硬度、耐磨性和断裂韧性等优点在精密刀具和模具方面备受青睐。近些年TiN纳米多层薄膜在力学性能方面的研究主要集中于超硬性能、摩擦磨损性以及断裂韧性三个方面。本文分别从膜层间作用关系、微观结构以及裂纹扩展机制等角度讨论多层构造对薄膜的超硬性能、耐磨性性以及断裂韧性的影响机理。提出超硬机理指导薄膜制备,残余应力影响裂纹的双重效应,建立多层微观结构与宏观力学性能映射关系三个研究方向,以期为研究TiN纳米多层薄膜力学性能提供新思路。另外,简单介绍了多层结构能够提升薄膜的高温抗氧化性和耐腐蚀性,并展望了TiN纳米多层膜的发展方向。     

超硬多层薄膜的研究现状及展望

超硬多层薄膜的性能随调制周期的变化而发生变化,在某一范围出现超模、超硬等异常效应.由于其潜在的实际应用价值及理论意义,超硬多层薄膜成为近年来人们研究的热点.综述了近年来国内外学者对超硬多层薄膜的研究结果,介绍了其超硬多层薄膜类型、主要性能特点以及制备工艺,并对未来的发展趋势进行了展望.     

石墨烯纳米复合多层薄膜的制备及应用

层层自组装技术制备的石墨烯纳米复合多层薄膜不仅拥有石墨烯优异的摩擦学、电学、热力学性能,且可基于协同效应产生新的特定功能如光催化活性、超润滑特性、抗菌活性等。根据多层复合薄膜的组装实质,从共价键和非共价键组装角度对石墨烯纳米复合多层薄膜的制备方法进行了综述,介绍了石墨烯复合薄膜在生物医学、电子器件、传感器等领域的应用,并对石墨烯复合薄膜的发展进行了总结和展望。     

叠层式TiO2/SnO2复合纳米薄膜制备及其光电性能研究

采用溶胶-凝胶法在不同基体表面制备了叠层式TiO2/SnO2复合纳米薄膜.用扫描电子显微镜(SEM)、X射线衍射(XRD)对复合薄膜表面形貌和晶体结构进行表征.采用紫外-可见吸收光谱法和电化学方法来研究复合薄膜光学与光电化学性能特征.结果表明,所制备的叠层式TiO2/SnO2复合纳米薄膜表面连续、均匀、致密;XRD分析表明纳米TiO2为锐钛矿型结构,SnO2为金红石型结构;紫外-可见吸收光谱测试表明叠层式TiO2/SnO2复合纳米薄膜较纯TiO2薄膜的吸收范围拓宽;稳定电位随时间变化曲线(OCP-t)结果表明,叠层式TiO2/SnO2复合纳米薄膜光照下其光电化学性能高于纯TiO2薄膜;同时,光照后叠层式TiO2/SnO2复合纳米薄膜能有效储存TiO2先生电荷,延续对不锈钢基体的光生阴极保护性能.经比较,叠加3层SnO2的TiO2/3SnO2复合纳米薄膜改善光电性能最佳.     

FeCuNbSiB／丁基橡胶复合薄膜压磁性能的研究

利用模压成型法制备了Fe73.5Cu1Nb3Si13.5B9非晶粉体/丁基橡胶和Fe73.5Cu1Nb3Si13.5 B9纳米晶粉体/丁基橡胶复合薄膜,采用4284A阻抗分析仪在20～50℃测试温度范围内研究了复合薄膜的压磁性能.结果表明,复合薄膜在＜0.09MPa微应力、低于200kHz测试频率下压磁性能最好;升高测试温度使复合薄膜的压磁性能增加,非晶粉体/丁基橡胶复合薄膜在40℃时压磁性能最好,纳米晶粉体/丁基橡胶复合薄膜在50℃时压磁性能最好;在相同条件下,非晶粉体/丁基橡胶复合薄膜的压磁性能优于纳米晶粉体/丁基橡胶复合薄膜.     

PCVD法制备硅系纳米复合薄膜材料

纳米复合薄膜材料由于具有传统复合材料和现代纳米材料两者的优点,成为重要的前沿研究领域之一.其中半导体纳米复合材料,尤其是硅系纳米复合薄膜,由于具有独特的光电性能,加之与集成电路相兼容的制备技术,有着广泛的应用前景.近年来关于纳米复合薄膜的研究不断深入,但仍有许多问题没有完全解决.本文围绕硅系纳米复合薄膜的材料特点,说明了等离子体化学气相沉积(PCVD)技术的工作原理和装置结构,以及该技术在硅系纳米复合薄膜制备中的独特优点.并以氮化硅薄膜为重点,介绍纳米复合薄膜材料的PCVD制备技术.文章最后对硅系纳米复合薄膜的在光电技术等各个领域的应用前景做了一些展望.     

纳米复合薄膜及其在果蔬保鲜中的应用

纳米复合包装薄膜一般为聚合物基纳米复合材料,可分为纳米材料/合成聚合物复合材料与纳米材料/天然聚合物复合材料。阐述了这2种复合材料的制备方法和性能特点,综述了纳米TiO2复合薄膜、纳米SiO2复合薄膜、纳米CaCO3复合薄膜、纳米银复合薄膜在果蔬保鲜中的应用研究,并展望了纳米复合薄膜在果蔬保鲜应用方面的研究方向。     

Influence of bias voltages on the structure and wear properties of TiSiN coating synthesized by cathodic arc plasma evaporation

Nanocomposite TiSiN films have been deposited on M2 tool steel substrates using TiSi alloy as target by a dual cathodic arc plasma deposition (CAPD) system. The influences of bias voltages on the microstructure, mechanical and tribological properties of the films were investigated. Scanning electron microscopy, transmission electron microscopy, X-ray diffraction techniques were employed to analyse the microstructure, grain size and residual stress. Nano-indentation and tribometer testers were used to measure the mechanical and tribological properties of nanocomposite TiSiN thin films. The results showed that the hardness of the films ranged from 25 to 37 GPa, which were higher than that of TiN (21 GPa). The coefficient of friction of the TiSiN thin films was more stable but was higher than that of TiN when wear against both Cr steel and WC-Co ball, respectively. When encountered with both Cr steel and WC-Co ball of the counter ball, the tribological mechanisms of TiSiN thin films are adhesive and abrasion wears, respectively. It has been found that the microstructure, mechanical and wear properties of the films were correlated to bias voltage, grain size, and amorphous Si₃N₄ nanocomposite formed in film structure, resulting in a superhard TiSiN coating.     

Synthesis and properties of CrNx/amorphous-WC nanocomposites prepared using hybrid arc ion plating and direct current magnetron sputtering

Hybrid deposition method was used to prepare CrN_x/amorphous-WC (CrN_x/a-WC) films. The effect of the arc ion plating and direct current magnetron sputtering on the changes in microstructure and properties such as hardness and thermal stability were studied. The amorphous WC phase of the CrN_x/a-WC films was confirmed by X-ray photoelectron spectroscopy and high resolution transmission electron microscopy. A bi-phase nanocomposite kinetic model and the Koehler's theory were used to explain the growth mechanism of CrN_x/a-WC films. A superhard superlattice Cr₂N/a-WC film with hardness up to ~ 48 GPa was abtained. The CrN/a-WC films displayed better resistance to oxidation than pure CrN and CrN-based films. As such, CrN_x/a-WC nanocomposite films are very promising for high-speed drying machines and other high-temperature applications.     

Evaluation of the internal friction and elastic modulus of the superhard films

In this paper, the vibrating-reed technique was used to measure the elastic modulus and internal fiction of the superhard thin films on the stainless steel substrate. The general formulas for evaluation of the internal fiction and the Young’s modulus of the film were derived for the sample with a rectangular section. The Young’s modulus of the nanocomposite superhard TiN/Si₃N₄ films on stainless steel is about 420–460 GPa at room temperature and decreases with increasing temperature. The internal fiction of the two-side deposited films is small and increases with temperature, while the internal friction of one-side deposited film is large and decreases with temperature due to the larger internal stress in the film.     

过渡族金属轻元素化合物薄膜强韧化的研究进展

由于过渡族金属具有极高的电子密度和抗压缩能力,而轻元素的共价键网络能强力抵抗形变,综合它们所长形成的化合物多为硬质(维氏硬度>20 GPa)甚至超硬材料(维氏硬度>40 GPa)。基于此,过渡族金属轻元素化合物薄膜为切削刀具、钻具、耐磨涂层和发动机部件等关键技术领域提供了重要的材料基础。然而,高硬度通常伴随着高脆性(低韧性),使裂纹萌生后快速扩展,导致材料在服役中突然断裂,从而降低材料的可靠性和使用寿命。因此,解决硬度与韧性的矛盾并实现材料综合性能的提高(强韧化)虽然极具挑战,但是意义重大。综述了过渡族金属轻元素化合物薄膜强韧化的常用手段和机理,介绍了在强韧化的基础上薄膜展现出的其他优异性能。通过全面总结分析,提出了薄膜强韧化亟待解决的科学问题和重要的研究方向。     

Superhard Nanocomposite Coatings

The recent development in the field of nanocomposite coatings with good mechanical properties is critically reviewed in this paper.The design principle and materials selection for the nanocomposite coatings are introduced.Different methods for the preparation of superhard nanocomposite coatings are described with emphasis on the magnetron sputtering.Based on recent theoretical and experimental results regarding the appearance of superhardness in nanocomposite coating,lattice parameter changes,crystallite size,microstructure and morphology are reviewed in detail.Also emphasized are the mechanical properties(especially on hardness)and the ways by which the properties are derived.     

低温PVD法制备多组分超硬薄膜相组成研究

回顾了多组分硬质薄膜的发展，指出了多组分薄膜低温淀积时相组成研究与预测存在的问题。对多组分硬质薄膜，包括类质同晶体系与多组分共熔体，低共熔体系、转熔体系、亚稳定固熔体与非晶固熔体，化合物，梯度薄膜，多相薄膜材料，多层薄膜和超晶格薄膜等可能的相组成与相关性质进行了讨论。对淀积速率与薄膜厚度，相组成与薄膜均质性，超晶格薄膜硬度与超晶格周期等的计算模型进行了评述。     

Measurement of hardness of superhard films by microindentation

A critical analysis is presented of the measurement by microindentation of the hardness of superhard films with hardness, H, exceeding 50 GPa. This analysis shows that a very high hardness of the Ti–Si–N nanocomposite film reaching a value of 105 GPa, which was recently reported, is hardly a correct value and so till now, very probably, no material harder than diamond has been prepared.     

超硬膜的研究进展

本文简要总结了近年来超硬膜研究领域中的一些最新进展,包括超硬膜硬度的理论研究和轻元素组成的超硬膜、纳米复合膜、纳米多层膜以及它们力学性能增强效应的理论解释．对超硬膜以后的发展趋势提出了自己的一些见解．     

Cubic boron nitride based metastable coatings and nanocomposites

Various PVD and plasma-assisted CVD methods presently used for the deposition of cubic boron nitride (c-BN) thin films demand adequate conditions relating to ion bombardment of growing films, growth temperature, film stoichiometry, etc. The deposition conditions, often appearing rather apparatus-dependent, can be well categorized according to the fundamental parameters of bombarding ions as well as condensing neutral particles, including their energy and flux ratio, and a few of others like ion mass and incident angle. According to these parameters, various surface kinetic processes and their consequences are discussed particularly in connection with the resulting film phases and stress. Typical c-BN films are known for their extremely high compressive stress and poor adhesion as a result of intensive ion bombardment during deposition. Individual measures attempting to relieve this detrimental stress are briefly summarized. The present paper focuses on magnetron-sputtered, c-BN-based metastable films and nanocomposite films with considerably reduced internal stress in comparison to the usual “pure” c-BN films. Two examples will be shown, namely c-BN/a-C nanocomposite and c-BN:O metastable films, including their deposition details, structure and composition characterization, and mechanical properties. Also illustrated is a growth scheme tailored for the deposition of thick, adhered, cubic-phase dominated, superhard c-BN:O films above 2 µm on silicon substrates.     

Synthesis and properties of corn zein/montmorillonite nanocomposite films

The objectives of this study were to apply fabrication techniques for the zein montmorillonite (MMT) nanocomposite films and characterize the obtained nanocomposite films. Zein MMT nanocomposite films were successfully produced from solvent casting and blown extrusion methods. The two methods could mix the zein MMT resulting in partially exfoliated nanocomposite structures according to X-ray diffraction and transmission electron microscopy. The thermal resistant of the zein nanocomposite films fabricated from both methods improved as the MMT content increased. However, the mechanical and barrier properties showed non-linear relationships with the MMT loadings. The impact of MMT on properties of zein films strongly depended on the preparation techniques. This can be the good starting point to further study in depth insight of the controllable MMT rearrangement in zein films which will remarkably improve zein film properties for packaging applications.