类金刚石薄膜纳米摩擦性能的试验研究

利用摩擦力显微镜(FFM),对由等离子体增强化学气相法沉积的类金刚石(DLC)薄膜的纳米摩擦性能进行了试验研究。用原子力显微镜(AFM)观察了DLC薄膜样品的表面形貌,同时测定了其粘附力值。从外加载荷、扫描速度和湿度的角度分析了薄膜的摩擦特性。     

工艺条件对类金刚石薄膜在不同介质环境下摩擦学性能的影响研究

考察了基底负偏压对类金刚石薄膜(DLC)在无水和有水环境下摩擦性能的影响。利用电子回旋共振等离子体化学气相方法沉积制备DLC薄膜,利用激光拉曼(Raman)、原子力显微镜(AFM)和纳米硬度计表征了其结构特征,用UMT型多功能摩擦磨损实验机考察了其摩擦性能,并用光学显微镜分析了磨痕特征。结果表明:随着基底偏压的增加,表面粗糙度减小;在无水条件下,基底偏压较低的DLC薄膜摩擦因数较高,并存在一定的波动性,基底偏压较高时,摩擦因数较低。在有水条件下,基底偏压对摩擦因数影响不大。总体来说,加水后薄膜磨损较为严重。     

超薄类金刚石膜纳米摩擦性能研究

使用原子力显微镜对由微波等离子体电子回旋共振化学气相沉积技术制备的超薄类金刚石薄膜的纳米摩擦性能进行了研究。结果表明：氢化非晶碳膜(a-C：H)的摩擦力和外加载荷基本成线性关系，可以使用修正的Amonton公式进行表征；厚度在64．9nm以下薄膜的微观承载性能和膜厚存在明显的正比例关系。通过分析磨损深度和循环次数之间的关系以及对磨损区域的导电性研究，表明a-C：H膜表层的微观承载性能较其内层相差很大，表面存在着一层软膜。     

类金刚石薄膜微观摩擦性能的FFM评价——针尖尺度效应

采用等离子体增强气相沉积制备了类金刚石薄膜，利用原子力显微镜的轻敲模式观察了它们的形貌，并在考虑外加载荷和扫描速度的基础上，用摩擦力显微镜（FFM）对比考察了尖端探针和平头探针对类金刚石薄膜摩擦性能评价的影响。结果表明：类金刚石薄膜的表面粗糙度随基底负偏压的增加而减小；存在于探针和类金刚石薄膜之间的水膜对尖端探针的剪切阻力贡献较大，且尖端探针测得的摩擦力变化趋势受扫描速度影响显著；水膜对平头探针起着不同形式的润滑作用，从而导致平头探针和类金刚石薄膜之间摩擦性能的速度效应存在差异；利用摩擦力显微镜考察类金刚石薄膜的摩擦性能时，存在着明显的针尖尺寸效应。     

类金刚石薄膜水润滑摩擦学特性研究进展

综述类金刚石薄膜水润滑摩擦学特性的研究进展,评述薄膜在水环境中的摩擦磨损特性,分析薄膜种类、元素掺杂、对摩材料以及微结构对DLC薄膜水润滑摩擦学特性的影响,并阐述DLC薄膜在水中的摩擦磨损机制。指出:DLC薄膜水润滑摩擦学特性受薄膜制备参数和摩擦试验环境影响,通过与微结构的耦合可以进一步改善类金刚石薄膜的摩擦学特性。同时还展望了类金刚石薄膜水润滑摩擦学未来研究方向。     

类金刚石薄膜

DLC是英文DIAMOND-LIKE CARBON一次的缩写。DLC是一种由碳元素构成、在性质上和钻石类似,同时又具有石墨原子组成结构的物质。类金刚石薄膜(DLC)是一种非晶态薄膜,由于具有高硬度和高弹性模量,低摩擦因数,耐磨损以及良好的真空摩擦学特性,很适合于作为耐磨     

MoS_2基复合润滑薄膜的制备及其摩擦性能

采用磁控溅射法在不锈钢基体上制备了MoS2/Ni复合润滑薄膜,研究了添加DLC(类金刚石薄膜)中间层对于MoS2/Ni复合薄膜的影响,探讨了复合润滑薄膜的减摩机理;使用EDS与XRD测定了复合薄膜的主要成分和物相结构,使用多功能摩擦试验机测定了薄膜的摩擦因数.结果表明:复合薄膜的主要成分为MoS2和Ni;薄膜中主要晶面为平行于基面的(002)晶面;复合薄膜的摩擦因数在0.06～0.18之间变化,且在高速重载的环境下具有更低的摩擦因数和更高的摩擦稳定性;中间层的加入进一步降低了复合薄膜的摩擦因数,达到0.04左右.     

The Tribological Properties of Low-friction Hydrogenated Diamond-like Carbon Measured in Ultrahigh Vacuum

In this paper, we investigate the sliding friction and wear behavior of a hydrogenated diamond-like carbon (DLC) film in ultrahigh vacuum (UHV) and under partial pressures of water vapor, oxygen, nitrogen and hydrogen. The initial friction coefficient of the film in UHV was ~0.15, but decreased steadily to values as low as 0.03 after about 30 sliding passes. During longer duration tests, the friction coefficient increased again to values as high as ~0.15 and such an increase in friction coincided with hydrogen desorption from the contacting surfaces (as detected by a mass spectrometer). Heating DLC to temperatures higher than 360 K also caused desorption of hydrogen and a resulting marked increase in friction. The presence of molecular nitrogen, oxygen and hydrogen in the test chamber did not have any noticeable effect on friction, but the presence of thermally dissociated or ionized hydrogen within the close proximity of sliding surfaces had a beneficial effect by restoring the low friction behavior of the DLC films. The introduction of water vapor into test chamber had an adverse effect on friction. The results of this study confirm that hydrogen is key to low friction behavior of hydrogenated DLC films and that the presence of water molecules has an adverse effect on their friction behavior.     

类金刚石碳基薄膜在1-乙基-3-甲基咪唑四氟硼酸盐中的摩擦学性能

利用射频等离子体增强化学气相沉积技术,以甲烷为气源,在单晶硅(P(001))衬底上制备类金刚石碳基薄膜(DLC);利用高速往复摩擦磨损试验机分别测试DLC薄膜/Al2O3球摩擦副在大气环境下和1-乙基-3-甲基咪唑四氟硼酸盐离子液润滑下的摩擦磨损性能;利用光学显微镜,X射线光电子能谱和三维轮廓仪分别对磨痕、磨痕表面元素和磨损率进行考察。实验结果表明:DLC薄膜在离子液润滑时,在低载荷下减摩作用明显,但在较高载荷下摩擦因数较无离子液润滑时高,且不随载荷增加而变化,推测是离子液形成了边界润滑膜;XPS分析表明这层边界润滑膜可能是由离子液物理吸附在摩擦接触面上形成的,并且对DLC薄膜有很强的抗磨作用。     

偏压对掺钨含氢类金刚石碳膜摩擦学性能的影响

利用非平衡磁控溅射技术在单晶硅片及9Cr18基体表面制备不同偏压下的掺钨含氢类金刚石碳膜。采用Ra-man光谱分析薄膜结构,采用纳米硬度测试仪和纳米划痕仪研究薄膜的纳米硬度、弹性模量和膜基附着力,在球-盘摩擦试验机上测试薄膜在大气环境中的摩擦学性能,研究薄膜的摩擦学性能与偏压的关系。结果表明:制备的薄膜样品均具有典型的类金刚石碳膜结构;基体偏压强烈影响薄膜的力学和摩擦学性能,薄膜硬度和弹性模量在0～150 V范围内随着偏压增加而增大,薄膜的摩擦因数在偏压为100 V时最小,在此参数下的耐磨寿命也最长。     

ECR-CVD制备类金刚石碳膜的正交实验法研究

采用系统的正交实验法对ECR-CVD法沉积类金刚石碳膜(DLC)的优化工艺进行研究,并分析不同工艺参数对DLC膜性能的影响.共选择基片温度、H2流量、微波功率、直流偏压、脉冲偏压以及脉冲偏压占空比6个参数建立起6因素5水平的正交表,分别以薄膜摩擦因数、磨损率、显微硬度、拉曼谱中D峰与G峰的面积比ID/IG作为考察对象进行研究.极差分析表明,对不同的考察因素其优化工艺略有区别.在所选的参数范围内,脉冲偏压对所测量的DLC膜的性能影响最大.     

Tribological Properties of Diamond-Like Carbon Films in Low and High Moist Air

Diamond-like carbon (DLC) film was deposited on Si wafer by a plasma CVD deposition system using benzene. Tribological properties of the DLC film were evaluated using a ball-on-disk tribo-meter in low (RH 1720 %) and high humidity (RH 9095 %) conditions in air. The effect of sliding speed (4.2 mm/s to 25 mm/s) and load (1.06 N to 3.08 N) on friction and wear was investigated. The friction behavior of the DLC film was obviously different in low and high humidity. When tested under low humidity conditions, the friction coefficient decreased significantly with increasing speed, and increased with load. However, under high humidity conditions, the friction coefficient increased with the speed and decreased with increasing load. The wear of the DLC film was little influenced by the sliding speed, normal load and humidity; a level of 10^-8 mm³/Nm could be obtained in all tests. The formation of a uniform transfer layer would be the main factor which controlled the friction coefficient of the DLC films. Unlike the friction, the wear resistance of the DLC film is not so easy to discuss and may be affected mainly by the tribo-chemical reaction in all the test conditions.     

类富勒烯碳薄膜的结构演变及摩擦学性能研究

通过等离子体增强化学气相沉积技术,以不同沉积时间在硅表面上制备类富勒烯碳薄膜,探究类富勒烯碳薄膜结构演变和摩擦学性能随沉积时间变化规律。利用拉曼光谱和透射电子显微镜,考察类富勒烯碳薄膜微结构和表面形貌随沉积时间的变化。结果表明:碳薄膜内类富勒烯结构含量随沉积时间先增加后保持不变;采用沉积时间为3 h的类富勒烯碳薄膜组成摩擦配伍对,当载荷从8 N增加到14 N时,摩擦因数从0.013降至0.006,即随载荷的增加实现了由低摩擦向超滑的转变。这是因为摩擦诱使类富勒烯碳薄膜发生结构转变,并形成有利于减少摩擦的类球状或外部石墨壳层闭合的纳米颗粒。     

射频磁控溅射法制备类金刚石薄膜的研究

采用射频磁控溅射法,纯Ar溅射石墨靶,制备出了类金刚石薄膜,并对薄膜沉积速率随各工艺参数的变化规律、薄膜结构以及光学性能进行了系统的研究。结果表明,沉积速率随射频功率、CH4流量和溅射气压的增大而增大;随温度的增大呈现先增大后小的趋势。结构分析发现,所制备的DLC薄膜是由sp2键镶嵌在sp3键基体中构成的。在3μm~5μm波段对Si衬底有明显的增透效果。