金刚石绳锯技术的发展和未来

金刚石绳锯是一种环保型的石材加工工具,极具发展潜力.文章叙述了绳锯的发展历史,展望了其广阔的市场和美好的发展前景;对三种不同串珠的制造方法和综合性能特征作了介绍;认为我国绳锯在矿山开采、异形石材加工和建筑市场方面前景看好,很可能在不久的将来替代砂锯加工硬质石材大板;最后对如何加快我国绳锯产业的发展提出了自己的看法.     

金刚石绳锯的最新进展

金刚石绳锯已经在石材切割和建筑工程领域得到了广泛的应用,一些新工艺和新方法被用于制作金刚石绳锯.采用串珠自动冷压成型技术,串珠热等静压技术,使生产效率得到大幅度提高,制作成本大幅下降;钎焊技术和金刚石定向排布技术提高了金刚石绳锯的综合性能.利用这些技术制作高性能的小直径绳锯和工程建筑用绳锯进一步扩大了绳锯的使用范围.     

浅述金刚石绳锯新领域应用

文章通过介绍金刚石绳锯在盐溶矿、纯钢切割的领域应用,概述了在盐溶矿、纯钢切割应用领域金刚石绳锯制备要求,配套设备情况以及应用情况,最后对金刚石绳锯在应用领域上提出建议.     

浅谈金刚石绳锯在钢筋混凝土切割中的应用发展

金刚石绳锯是集金刚石高硬度与钢丝绳高柔性为一体的石材加工工具,其具有资源利用率高、环境影响小、施工简单等一系列优点,能实现各种异形面加工、大型土建拆迁和管道施工等工程领域的高效切割,发展潜能巨大。文章阐述了金刚石绳锯在钢筋混凝土切割领域的发展历史,并结合目前国内外相关基础理论研究以及实际切割应用,最后就金刚石绳锯在这一领域的应用前景提出自己的一定看法。     

浅谈几种金刚石绳锯板材加工方式

文章通过介绍金刚石绳锯岩石板材加工方式,详细概述了金刚石绳锯板材异形加工、花岗岩大板加工、奢石大板加工的设备、规格尺寸、加工特点、应用说明、加工不足及发展趋势,最后对金刚石绳锯在板材加工领域提出建议。     

回转支承在金刚石绳锯机上的运用

文章介绍了目前国产金刚石绳锯机的技术状况、回转支承的结构及其在金刚石绳锯机中的选型及运用。讨论金刚石绳锯机采用蜗轮箱结构和采用回转支承结构的优、缺点。     

金刚石串珠绳锯橡胶配方设计研究初探

文章在金刚石串珠绳锯对橡胶材料要求的基础上,从生胶选择、硫化体系、补强填充体系、软化体系,粘合体系等各方面对绳锯橡胶进行了细致的配方设计分析,并对硫化工艺中的常见问题提出了具体解决办法。     

锯切线速度对FeCuCo基结合剂金刚石绳锯性能影响

采用FeCuCo基结合剂为原料和优化的制作工艺,以金刚石参数设计理论为依据,根据被切割石材的基本特征,制作出了金刚石绳锯进行石材矿山切割实验,研究绳锯线速度V_s对FeCuCo基结合剂金刚石绳锯锯切性能的影响规律。研究结果表明：不同线速度时,随着锯切的进行和串珠直径的逐渐消耗,绳锯锯切效率逐渐提高,而工具理论寿命逐渐降低;随着锯切线速度的增加,绳锯串珠表面单颗金刚石平均切削厚度h_c值呈逐渐减小的趋势;随着锯切线速度降低,绳锯串珠表面完整态金刚石出刃高度平均值呈逐渐升高的趋势,且锯切线速度越小,绳锯串珠表面金刚石出刃高度越大;随着锯切线速度的提高,岩屑D50粒度呈现逐渐降低的趋势,且明显远大于单颗金刚石平均切削厚度h_c值,这是由于金刚石颗粒的切削机理属于有裂纹扩展的“体积破碎”方式产生的。     

金刚石绳锯注塑工艺中在线加热技术的试验研究

针对金刚石绳锯在使用过程出现的串珠窜动、塑料脱落、钢丝绳磨断等问题,对金刚石绳锯生产工艺中的在线加热技术进行了试验,结果表明,采用在线加热技术使金刚石绳锯中钢丝绳、塑料、串珠之间的粘结强度得到了明显提高.     

一种新的金刚石绳锯系统的开发及其在建筑施工中的应用效果

根据绳锯系统的开发及其在建筑施工中的应用,着重对该资料在设备开发、绳锯系统的改进设计、新绳锯的试验及其应用效果等方面作详细介绍.研究指出,新的绳锯系统具有设备重量轻、体积小、便于操作且绳锯消耗低、噪音小、污染少的优势.     

氮与金刚石性能关系综述

氮是金刚石晶体中最最常见的杂质,也是影响金刚石性能的重要因素之一.关于氮对金刚石合成及其性能的影响研究,很多研究者根据各自所得到实验与分析结果做出了许多有价值的描述.文章对其中有一定科学技术意义和对实际有指导作用以及帮助我们了解其最基本性能的内容做一简要综述.     

镀覆金刚石技术的研究进展

金刚石工具中存在的把持力不足、颗粒脱落、氧化石墨化等问题,严重影响了工具的使用寿命和效率.金刚石表面镀覆金属层是解决这一问题的有效方法.文章对金刚石表面镀覆条件、镀覆原理和形成的镀覆金属化模型进行了讨论,综述了金刚石表面镀覆金属层的技术及其发展,介绍了该领域的最新的研究成果,并分析了它们在实际生产中应用.     

Comparison of different oxidation techniques on single-crystal and nanocrystalline diamond surfaces

Various oxidation techniques (plasma-beam, sulfo-chromic acid, UV-ozone, heating in air) were applied to single-crystalline (111) and (100) diamond surfaces as well as nanocrystalline diamond (NCD) films and analyzed by X-ray photoelectron spectroscopy (XPS) with respect to oxygen content and type of carbon–oxygen groups formed upon oxidation. Due to their increased surface, NCD films show a significantly higher oxygen uptake as compared to their single-crystal counterparts. No marked differences were observed between the different oxidation techniques. For all oxidation techniques used, several carbon–oxygen groups are simultaneously present on the surface. The relative fraction of singly-oxidized carbon atoms (attributed to isolated ether or epoxy-like groups) generally decreases slightly with increasing oxygen content, but always remains the dominating species.     

Edge termination techniques for p-type diamond Schottky barrier diodes

The superior material properties of diamond power semiconductor devices make them a crucial technology. For high-voltage applications, optimized structures such as electric field edge termination are required for devices. In this paper, we have investigated the optimization of electric field relaxation techniques in oxygen-terminated p-type diamond Schottky barrier diodes and made comparisons with regard to electric field crowding and breakdown in oxides. Due to the low dielectric constant of diamond, Al₂O₃ is appropriate for the fabrication of field plate structures in diamond power devices.     

CVD金刚石薄膜技术发展现状及展望(下)

简要描述了CVD金刚石薄膜技术的发展历程。介绍了纳米特别是超纳米金刚石膜、CVD金刚石大单晶的技术特点及其应用。超纳米金刚石膜在MEMS(微机电系统)、电化学和生物医学上的应用和CVD金刚石大单晶是当前的研究热点。简言之,金刚石的发展向着更大或者更小的方向深入进行,即"非大即小"。     

CVD金刚石薄膜技术发展现状及展望(上)

简要描述了CVD金刚石薄膜技术的发展历程.介绍了纳米特别是超纳米金刚石膜、CVD金刚石大单晶的技术特点及其应用.超纳米金刚石膜在MEMS(微机电系统)、电化学和生物医学上的应用和CVD金刚石大单晶是当前的研究热点.简言之,金刚石的发展向着更大或者更小的方向深入进行,即“非大即小”.     

Deposition of diamond films on sapphire: studies of interfacial properties and patterning techniques

Polycrystalline diamond films were grown on single crystal sapphire substrates using hot filament chemical vapour deposition (CVD). Problems with poor adhesion, stress and film cracking became severe for deposited areas greater than about (100 μm)². Scanning electron microscopy analysis showed the films to be failing both at the interface and in the diamond layer itself. Transmission electron microscopy cross-sections of the interface showed that the interface was clean and free from non-diamond carbon impurities. Spallation problems in the diamond film could be reduced by introducing a barrier layer of epitaxial silicon grown on the sapphire prior to the diamond CVD step. Patterned silicon-on-sapphire wafers were then used as substrates for CVD of diamond in order to define features of linewidth more than 10 μm in the diamond films. Two methods were used: selective nucleation and lift off.     

镀钛金刚石制备金刚石聚晶的研究

在国产六面顶高压设备上,以镀钛金刚石为原料,镍基合金为烧结助剂,采用熔渗法成功制备了金刚石聚晶(PCD),通过扫描电镜(SEM)、X射线衍射(XRD)、拉曼光谱(Raman)等测试方法,研究了不同烧结压力和温度对镀钛金刚石聚晶组织形貌的影响,与普通金刚石聚晶进行了物相成分及残余应力的对比分析。实验结果表明:烧结条件为5.4~5.6GPa,1350℃~1450℃下的镀钛PCD具有较高的致密性和机械性能;镀钛PCD的衍射峰中有NiMnCo、碳化钛和TiMnC化合物。镀钛PCD相比普通的PCD表面残余应力略大。     

Pre-nucleation techniques for enhancing nucleation density and adhesion of low temperature deposited ultra-nanocrystalline diamond

Effect of pre-nucleation techniques on enhancing nucleation density and the adhesion of ultra-nanocrystalline diamond (UNCD) deposited on the Si substrates at low temperature were investigated. Four different pre-nucleation techniques were used for depositing UNCD films: (i) bias-enhanced nucleation (BEN); (ii) pre-carburized and then ultrasonicated with diamond powder solution (PC-U); (iii) ultrasonicated with diamond and Ti mixed powder solution (U-m); (iv) ultrasonicated with diamond powder solution (U). The nucleation density is lowest for UNCD/U-substrate films ( 10⁸ grains/cm²), which results in roughest surface and poorest film-to-substrate adhesion. The UNCD/PC-U-substrate films show largest nucleation density ( 1 × 10¹¹ grains/cm²) and most smooth surface (8.81 nm-rms), whereas the UNCD/BEN-substrate films exhibit the strongest adhesion to the Si substrates (critical loads =  67 mN). Such a phenomenon can be ascribed to the high kinetic energy of the carbon species, which easily form covalent bonding, Si–C, and bond strongly to both the Si and diamond.     

Oxygen on diamond surfaces

Studies into the effect of hydrogen and oxygen on the growth of CVD diamonds have been in progress for a number of years. Surface oxygen studies on natural diamond using Rutherford backscattering spectrometry have yielded partial monolayer coverage on low index planes. To increase the sensitivity of the measurements, elastic scattering using the ¹⁶O(α,α)¹⁶O resonance at 3.045 MeV has been performed. This resonance can enhance, by up to 30 times, the Rutherford cross-section. The samples are natural diamonds with either (111) or (100) surfaces. These have been cleaned using aqueous and acidic solvents to study the effect cleaning has on the oxygen coverage. We have found the coverage to be dependent on the vacuum level of the target chamber, with no effect being shown by the cleaning methods.