铜包铁结合剂在金刚石锯切工具中的应用研究

铁基结合剂金刚石工具是目前石材加工业常用的锯切工具,但是这类工具由于产品性能不稳定等缺点使其应用受到了限制。本文研制了一种铜包铁颗粒,采用化学置换反应在铁粉颗粒表面包覆一层铜粉末,以这种粉末作为铁基金刚石锯切工具的主要成分,同时,对金刚石表面进行盐浴镀钛处理。结果表明,这种铁基金刚石锯切工具烧结温度区间较宽,产品性能对烧结温度不敏感,性能可与铜基结合剂金刚石工具媲美,是一种值得推广的铁基金刚石工具结合剂。     

铸铁短纤维结合剂金刚石锯片、砂轮

铸铁短纤维金刚石砂轮(包括金刚石圆锯片、磨头等)是国际上80年代新技术、新产品。该金刚石制品主要用于工程陶瓷、玻璃、石材等硬脆材料的磨削加和切割加工。     

锯切花岗岩过程中金刚石框架锯的锯切力研究

锯切力是影响金刚石框架锯锯切板材质量的重要因素。本文通过对锯切机的运动学分析,研究锯条受载的变化情况与主要加工参数(进给速度v、参与锯切锯齿数n、和飞轮转速ω)对锯切力的影响机理,建立了最大锯切深度的计算模型。采用响应曲面法设计三因素三水平的金刚石框架锯锯切花岗岩试验,建立法向、水平锯切力关于主要加工参数的二阶预测模型,分析各因素对水平、法向锯切力的影响情况。通过ABAQUS有限元仿真软件对张紧后的锯条进行非线性屈曲分析,得到其临界屈曲载荷,进而得到在25个锯齿参与锯切条件下不发生临界屈曲的最优加工参数组合为进给速度v=62.94mm/h,飞轮转速ω=70r/min。     

基于小波分析的金刚石锯片锯切混凝土加工状态及表面质量分析

针对不同骨料加工性差异较大,导致混凝土锯切情况复杂多变、难以进行加工状态及表面质量有效监控的问题,利用金刚石锯片分别对软骨料、硬骨料及混凝土展开锯切试验,利用小波分析多尺度转换研究了硬软骨料单一成分锯切力信号在不同尺度上的基本特征及其与关联维数的关系,并利用单一成分关联维数特征判断混凝土加工状态及表面质量。结果表明,锯切力的a7尺度信号特征可用于判断硬软骨料的比重,d3尺度信号关联维数代表了混凝土材料的脆性断裂程度及表面加工质量。     

高速锯片锯切检测试验机的研究与开发

针对现有锯切试验方法的缺陷,分析了高转速锯片锯切试验对锯切试验机及其零部件的要求,提出了锯切试验机的总体方案设计及各零部件的具体解决方案,指出后续工作方向。     

金刚石圆锯锯切花岗岩锯切参数对耐用度的效应试验研究

采用正交回归试验方法，探讨锯切花岗岩参数对金刚石圆锯耐用度的主效应和交互效应，求出试验公式，并对生产实际提出出合理化建议。     

用金刚石丝锯进行精密切割

<正> 钢丝锯切割是当今市场上最普通的切割方法之一。它使用一根张紧的钢丝,在工件上从一端向另一端往复运动。将金刚石嵌入钢丝后,它可以切割整个硬度范围的任何材料,从软的金属和陶瓷到最硬的材料。金刚石丝锯用的钢丝必须有足够的抗张强度,以承受所需的张     

岩石材料的金刚石锯切研究进展

使用金刚石工具的锯切加工是切割天然岩石材料的最主要方式。在过去的50年中,伴随着人造金刚石的诞生和规模化生产,人类在石材的金刚石锯切技术研究和开发方面取得了显著成就。回顾了金刚石锯切石材的两个历史阶段;总结了金刚石节块技术、锯切机理以及机床方面的研究成果;讨论了金刚石锯切技术的发展趋势。     

大切深锯切石材中锯片受力的有限元分析

通过测量大切深锯切石材条件下锯片承受的垂直力、水平力以及主轴消耗的净功率,分析了锯切力在锯切弧区内合力作用点的位置,确定了锯切弧区内载荷的分布情况.在此基础上,利用有限元方法对某一典型锯切参数下锯片基体和锯切弧区内锯齿端面的应力分布情况进行了计算分析.采用屈曲分析研究了使锯片丧失稳定性的临界载荷及其影响因素.研究表明,锯切弧区内锯切载荷基本上按三角形规律分布.锯切弧区内金刚石节块表面前后端应力存在梯度,而且随着节块长度的增大而增大.锯片的临界载荷随着锯片厚度、转速和夹紧比的增大而增大,随着锯片直径的增大而减小.     

金刚石线锯超声复合锯切的运动轨迹研究

通过对金刚石线锯超声复合锯切进行运动学分析,阐述金刚石线锯在锯切过程中的一些特征,由此可为金刚石线锯工具开发和加工工艺参数的优化选择提供基本参考依据,并能为超声锯切过程的深入研究打下理论基础.     

环形电镀金刚石线锯对花岗石锯切机理的研究

论述用环形电镀金刚石线锯锯切花岗石时脆、塑性转变的临界条件,研究认为,提高锯丝的锯切速度,有利于花岗石由脆性向塑性转变。用自制的试验设备对花岗石进行锯切试验,试验结果表明,当花岗石的锯切深度小于其脆、塑性转变的临界深度时,花岗石可以实现塑性域锯切,锯切表面光滑,质量较好。     

金刚石圆锯片锯切花岗石的切削力双因素实验研究

基于金刚石圆锯片锯切五莲红花岗石的双因素实验,对切削速度和进给速度与切削力的关系进行研究.通过极差分析和趋势图得出进给速度是影响切削力Fx、Fy、Fz的主要因素,切削力随切削速度的增大而减小,随进给速度的增大而增大.通过回归分析建立了切削力数学模型,为生产中根据给定的加工参数来预测切削力提供了理论支持.     

激光切缝图形对金刚石圆锯片噪声的影响

根据金刚石圆锯片基体上激光切缝图形降低噪声的原理，设计了几种激光切缝图形的消音金刚石圆锯片；对金刚石圆锯片的噪声进行了对比测试研究，分析了不同激光切缝图形、喷水、槽宽等各种因素对噪声的影响。结果表明金刚石圆锯片基体上合理的激光切缝图形降低噪声的效果是相当明显的。     

多参数金刚石圆锯片锯切性能试验机的研制

专门研制出一种多参数的试验机,用以检测石材加工所用的金刚石圆锯片的锋利度、耐磨性等锯切性能。简介了该试验机的系统组成,具体指出了用来衡量金刚石圆锯片的锯切性能的锯切功率、锯切阻力、锯片转速、给进速度和噪声等多种参数的检测和控制工作原理,给出了基于LabVIEW的锯切参量检测程序设计面板和噪声检测程序代码。该系统测控操作简便,具有很强的适应性,满足综合评价金刚石圆锯片锯切性能的基本要求。     

Analysis of the diamond sawing process

There are three methods in use for separating diamonds, i.e. by cleaving, by laser beam and by sawing. Sawing is one of the main methods used for this purpose. This operation is carried out on special sawing machines equipped with a sawing disk blade, 0.04–0.14 mm thick and 76 mm initial diameter. The rotational velocity (n) of the disk is between 6000 and 12 000 r.p.m. Diamond powder is embedded in the periphery of the disk. The outcome surface of a diamond after the sawing operation must be flat and smooth, Whenever such a surface is actually obtained, the polishing time and the loss in size and weight of the diamonds are reduced.In the present work, the positioning of the diamond to be sawed, with respect to an embedded particle in the disk, to create a favourable cutting angle is discussed. This would make it possible to reduce the rake angle () to near-zero, and thereby the cutting forces. Furthermore, a method to control the morphology and grain size of the diamond powder to be used in the cutting was developed.In the diamond industry, two modes of sawing operations are in practice. One uses the periphery of the disk for the sawing while the other employs a circular hole in the centre of the disk. Analysis of the two modes showed that the hole mode is more promising, as the design in that case requires tensioning of the disk and makes for better lateral stability during the sawing process. In addition the tangential and the radial stresses, developed in both sawing methods, were calculated. To support the above, data was obtained from existing literature and analysed.Nomenclature n rotational velocity of the disk, r.p.m. - rake angle, degrees - back clearance angle, degrees - cutting angle, degrees - m relative frequency - f feed - b disk radius, mm - a disk hole radius, mm - r current disk radiusb>r>a, mm - density of disk material, kg m^–3 - angular velocity - Poisson ratio of disk material - g acceleration of gravity, m s^–2 - _r radial stress, kg cm^–2 - _{r max} highest radial stress, kg cm^–2 - _t tangential stress, kg cm^–2 - tangential stress at outside circumference, kg cm^–2 - tangential stress at inside circumference, kg cm^–2     

Study on the thermal wear of diamond segmented tools in circular sawing of granites

An investigation is reported of an analysis on the thermally induced sawblade wear in circular sawing of granites with diamond segmented tools. The temperatures at the diamond–workpiece interface were measured in dry sawing using a foil thermocouple in order to examine the contribution of temperatures to the wear of the segments. Scanning electron microscope and energy dispersive spectrometers were employed to analyze the mechanisms for the bonding of Ti/Cr-coated diamonds to an iron-based matrix. Over 90% of the consumed energy was found to conduct into the diamond segments as heat in the sawing. Strong metallurgical bonding was observed at the diamond–matrix interface and subsequently the retention ability of the matrix to diamonds was increased. However, the retention effect of the coating was greatly offset by the disparity of diamond crystal strength, which could be improved by multistage shape selecting and magnetic separating. Coupled with the mechanisms for thermal wear, attempts were made to reduce thermally induced wear by using Ti/Cr-coated diamonds, reducing the disparity of diamond crystal strength, designing unique structured segments and selecting optimal machining parameters.     

金刚石圆锯片模态分析

金刚石圆锯片锯切过程中,普遍存在着严重的振动问题。为研究金刚石圆锯片的动态性能,通过ANSYS有限元分析软件建立锯片三维参数化模型,并利用不同的有限元网格划分方法分别进行模态分析,得到固有频率和振型,最后通过采用锤击法对金刚石圆锯片进行模态试验。对比多组不同直径的锯片有限元分析结果和模态试验结果可见,不同的网格划分方法对有限元模态分析结果影响较大,而映射分网的有限元模态分析结果更接近试验结果。利用该模型可代替试验对金刚石圆锯片进行参数化模态分析,为进一步研究锯片的振动可靠性和稳定性问题打下了基础。     

水下金刚石绳锯耐磨损率的实验研究

为了实现海底石油管道切割作业,采用均匀设计方法对水下金刚石绳锯串珠绳的耐磨损率影响进行了试验研究.使用MINITAB软件,建立了主要工艺参数对耐磨损率的多元线性回归方程,进行了回归分析,求得了绳锯耐磨损率较为精确的经验公式.进一步探讨了水下金刚石绳锯耐磨损率的工艺规律,为满足绳锯机设计要求和优化工艺参数提供了理论依据.     

Experimental investigation on cutting mechanisms in fixed diamond wire sawing of bone

Bone sawing has been widely used in performing bone surgery. However, thermal necrosis, loss of cutting precision and surface damage may occur in cutting process. The primary objective of this research is to improve cutting performance of bone by advantages of diamond wire sawing. Mechanism of material removal, cutting force, temperature and surface quality are analyzed based on experimental results. It is indicated that wire sawing provides small depth of cut, which is effective to obtain ductile material removal mode. Due to small material removal rate per abrasive, thermal energy is low and most of the heat can be taken away by the cyclic wire and bone chips. Consequently, cutting force and temperature in cutting zone are lower than that of traditional sawing. Due to the high efficiency of chip ejection, burrs and fracture are reduced and a significant improvement in surface quality is achieved. Based on cutting experiments with various values of cutting parameters, it is observed that better performance is achievable at higher wire speeds. These results provide a valuable basis for application of wire sawing and understanding of bone cutting mechanisms.