共查询到20条相似文献,搜索用时 78 毫秒
1.
2.
使用Abaqus有限元软件通过加载荷与加载位移两种方法对含硅类金刚石膜进行了压痕测试模拟,得到了不同硅含量类金刚石膜的硬度曲线。结果表明:两种方法的模拟结果较吻合,其中加载位移的方法较稳定,速度较快,含硅类金刚石膜的硬度随着硅含量的增加而减小;模拟结果得到了相关试验的验证。 相似文献
3.
4.
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。 相似文献
5.
6.
7.
单晶硅纳米力学性能的测试 总被引:1,自引:0,他引:1
对材料纳米力学性能测试手段进行了研究,着重分析了纳米压痕技术的原理和方法.结合纳米压痕技术,采用尖端四面体Vickers型单晶金刚石压头对单晶硅(100)晶面进行了纳米压痕实验测试.实验发现,在载荷为1 000 mN时,晶体硅出现了明显的裂纹和脆性断裂;而在载荷低于80 mN的情况下,晶体硅则表现出延性特性.此外,在不同载荷条件下对晶体硅的硬度进行了实验测试,测试结果发现,不同载荷条件下晶体硅的硬度测量值存在较大的差异,认为导致这种差异的原因在于压痕区域晶体硅所受压力不同,使得晶体硅内部结构发生了改变,较为准确的单晶硅的硬度测量值为15.7 GPa. 相似文献
8.
纳米金刚石薄膜的制备与应用 总被引:4,自引:0,他引:4
采用偏压辅助增强热丝化学气相沉积法(Chemical vapor deposition,CVD),以WC-Co硬质合金为衬底,采用控制沉积参数和添加惰性气体Ar等CVD新工艺,制备性能优良的纳米金刚石薄膜.进一步采用扫描电镜(Scanning electron microscopy,SEM)、原子力显微镜(Atomic force microscopy,AFM)、拉曼光谱(Raman spectroscopy)、X射线衍射(X-ray diffraction,XRD)和高分辨率透射电镜(High-resolution transmission electron microscopy,HR-TEM)分析了薄膜的纳米效应.研究结果表明:纳米涂层仍然是以金刚石结构为主的多晶体,它晶体颗粒较小(20~80 nm),含有较多的晶界和sp2结构,涂层表面粗糙度Ra≤50 nm,表面平整光滑,有利于研磨抛光.在此基础上,提出纳米金刚石复合涂层制备新技术,开发研制出各种涂层拉拔模具,在实际生产线上进行了应用,取得了显著的效果. 相似文献
9.
采用磁控溅射方法在不锈钢表面制备了铜原子分数在0~11.8%的Al-Cu合金薄膜,研究了铜含量对薄膜微观结构、纳米压痕力学性能和强化机制的影响。结果表明:纯铝薄膜呈现面心立方结构,铜原子分数在2.2%~6.5%时Al-Cu合金薄膜均形成过饱和固溶体相,当铜原子分数超过6.5%后,薄膜中生成了AlCu化合物。随铜含量的增加,薄膜的晶粒尺寸减小,硬度和弹性模量增加,当铜原子分数增至11.8%时,晶粒尺寸为34.7 nm,硬度和弹性模量分别比纯铝薄膜提高了212.5%,2.2%;当铜原子分数在0~6.5%时薄膜的强化主要来自于细晶强化和固溶强化,当铜原子分数超过6.5%后,薄膜的强化是细晶强化、固溶强化和第二相强化共同作用的结果。 相似文献
10.
11.
12.
抓住机遇,推动我国微型机械的快速发展 总被引:15,自引:4,他引:11
阐明微型机械新型学科的内涵和广阔的应用前景。综述美、日等发达国家从事微型机械的研究与开发状况和国内微型机械的研究现状。提出了推动我国微型机械快速发展的建议。 相似文献
13.
Tribological performance of diamond-like carbon (DLC) overcoat on a magnetic hard disk was evaluated using a contact start
stop wear tester. The analysis of worn surfaces suggests that wear of the carbon overcoat took place by a delamination type
of wear mechanism at a nanoscale, resulting in the formation of wear particles of about 1.5 nm thick and 30–90 nm wide.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
14.
Components used in magnetic storage systems (hard discs, tape heads and drums) are often very small and lightweight, and operate under very low loads (of the order of a few micrograms to a few milligrams). As a result, friction and wear processes occur on a nanometre scale and conventional tribological test methods and assessment tools are usually not appropriate. Furthermore, the assessment of the mechanical properties of the coatings or surface treatments used to protect these components from wear is complicated by the low thickness of the layers generally used. This paper details the problems associated with the assessment of the mechanical properties of thin diamond-like carbon coatings used to protect hard discs, tape heads and air bearings. Whereas thick coatings (>1 μm) are relatively easy to assess, even if the substrate has a low hardness and offers little support to the coating, there are many more problems when it comes to measuring the properties of the 5–10 nm layer on a hard disc. In many cases there is no plastic deformation of the coating which merely flexes and bends into the hole produced by plastic deformation of the substrate. Deformation of the coating is then limited to localised plasticity at the indenter edges, and/or fracture along the same edges and at the edge of the contact. The limits for use of Nanoindentation to assess the plasticity of the coating are discussed for such cases. 相似文献
15.
16.
The low contact pressure characteristic of the microtribological regime relative to macro and nanosystems is suited for testing the microfrictional properties of different types of thin films. Motivated by macro as well as microsystem applications, this study investigates the microfrictional properties of different types of diamond-like carbon (DLC) films, prepared using low- and high-frequency plasma-assisted chemical vapor deposition (HF-PACVD) and the vacuum arc method. Testing was performed with a reciprocating precision microtribometer. Silicon, sapphire and steel balls were used as counterbodies. Friction-load curves suggest that, for applied forces in the μN to mN regime, two properties have a strong influence on the microfriction: first, the chemical composition plays a dominant role and second, the film roughness. With silicon and steel balls, the microfriction of hydrogen-free DLC films was greater than the hydrogen-containing films. With sapphire counterbodies, the results indicate that microfriction is inversely proportional to the film roughness. Also, for the films tested, microfriction was determined to be independent of the sliding velocity. For the force (pressure) regimes tested, mild wear was observed on silicon and some steel counterbodies, while no wear could be detected on any of the DLC films. These results illustrate the utility of implementing microtribological testing in comparative coating studies. 相似文献
17.
18.
19.
20.
飞秒脉冲激光沉积类金刚石膜实验研究 总被引:1,自引:0,他引:1
期望用类金刚石膜作为硅的红外保护/增透膜,采用波长为800nm,脉宽50fs,重复频率1KH z的T i:Sapph ire飞秒激光器及石墨靶材在单晶S i片上沉积了约0.7μm~1μm厚的类金刚石膜(d iam ond-like carbon film s,DLC),获得了光滑致密,硬度显著提高,红外透过率有一定增加的样品。通过对薄膜拉曼光谱和X射线光电子能谱等的测试,发现单脉冲能量在0.4m J~1.6m J范围内变动时,单脉冲能量0.8m J获得的类金刚石膜综合性能最佳,其对应的焦斑功率密度计算值为1.4×1014W/cm2。 相似文献