电加工技术在修整金属结合剂超硬磨料砂轮中的应用

介绍了电加工技术在修整金属结合剂超硬磨料砂轮中的应用。电加工修整技术针对金属结合剂和磨料的不同电特性，对结合剂进行蚀除，不仅有助于提高金属结合剂超硬磨料砂轮的修整效率和质量，而且具有较好的应用前景。     

砂带修锐树脂结合剂CBN砂轮的研究

砂带修锐树脂结合剂ＣＢＮ砂轮的研究南京航空航天大学李迎，徐鸿钧，张幼帧一、砂带修锐原理超硬磨料磨具的修整分整形和修锐两个过程．而修锐是目前超硬磨具修整工作中的难点。电解在线修锐成功地解决了金属结合剂超硬磨料磨具修锐问题（１），使树脂结合剂ＣＢＮ砂轮的...     

双电极接触放电法在金属结合剂CBN砂轮修整中的应用研究

双电极按触放电是一项修整金属结合剂超硬磨料砂轮的新技木。它利用接触放电电蚀原理以达到去除砂轮的金属结合剂而修锐或整形砂轮。本文在论述修整机理的基础上．对其工艺规律进行了系统的分析和总结．     

超硬磨料砂轮修整及点轮修整技术

与普通磨料砂轮相比,采用金刚石车削法修整超硬磨料砂轮,修整力大、工具磨损快、修整时间长、效率低、精度低及质量差,致使超硬磨料砂轮的优异性能得不到充分发挥,砂轮修整已经成为制约超硬磨料砂轮工程应用的主要瓶颈.在超硬磨料砂轮修整研究方面,科研成果众多,技术各有特点,然而工程应用有限.点轮修整是集金刚石车削修整、金刚石滚轮磨...     

ELID镜面磨削技术——砂轮快速修整技术的研究

介绍了ELID磨削中采用电火花整形装置对金属结合剂超硬磨料砂轮进行整形修整的技术。修整后的砂轮径向跳动量小于1μm,砂轮表面光滑,形状精度高,磨粒等高性好,适于精密镜面磨削用,具有修整时间短、成本低、砂轮损耗小的优点。     

金属结合剂超硬砂轮的电加工修整

金属基超硬磨料砂轮耐磨及刚性好，但整形、修锐困难。本文介绍对金属基超硬砂轮的电火花修整、接触式电火花放电修整及电解放电修整，并着重介绍电解-机械循环复合精密修整技术。机械修锐金属基砂轮．磨料后面留有隆起的金属形成磨粒尾部，在磨削时会增加磨粒的粘附强度，可防     

电火花修整超硬磨料砂轮技术发展现状

电火花加工技术的发展带动了电火花修整超硬磨料砂轮技术,改变了传统砂轮“硬接触”修整方法。近年来,许多学者致力于研究超硬磨料砂轮的电火花修整方法,为提高磨削效率和磨削精度做了大量有意义的研究。基于大量文献的论述与研究,回顾了近三十年来电火花修整超硬磨料砂轮技术发展过程的各种研究内容以及取得的成果,完整地阐述了电火花修整金属基超硬磨料砂轮技术的基本原理。以立方氮化硼(CBN)和金刚石磨料砂轮修整为主要应用,对不同电极、不同放电介质、不同放电参数以及现代工程理论辅助下的建模分析方法等方面做了介绍,分析了现有电火花修整技术发展中存在的问题,探讨了未来发展的方向及趋势。     

复合电加工修整金刚石砂轮的研究

复合电加工修整金刚石砂轮技术,其方法简单实用,不仅能够修整金属结合剂的砂轮,也能修整树脂结合剂的砂轮。详细介绍了复合修整机理及修整效果。     

硬质合金超精密镜面磨削的实验研究

采用金属结合剂超硬磨料砂轮在线电解修整 (ELID)精密镜面磨削技术 ,对几类常用的硬质合金分别进行了精密镜面磨削实验 ,获得Ra6～ 17nm的高质量表面。     

超硬磨料砂轮的激光修锐技术研究

激光修整超硬磨料砂轮的原理,利用Ｎｄ：ＹＡＧ固体脉冲激光器进行激光修锐青铜结合剂和树脂结合剂硬磨料砂轮的试验,用扫描电镜观察了激光修锐前后砂轮表面的微观表貌,对激光作用下砂轮表面不同结合剂材料的去除机理进行了分析,通过磨削陶瓷试验,研究激光修锐的金刚石砂轮的磨削性能,并与普通砂轮磨削肖修锐的金刚石砂轮进行对比。结果表明,采用试验所确定的激光参数可选择性地去除砂轮表面的结合剂材料,而不损伤超硬磨粒,     

金属基结合剂超硬砂轮的电火花修整

采用自行研制的ELID磨削专用脉冲电源对金属基结合剂超硬砂轮进行电火花整形 ,分析了不同电火花整形方式的电路原理及整形效果 ,并对砂轮的电火花整形机理及整形效率进行了研究。研究结果表明 ,采用方波脉冲式电火花修整金属基结合剂超硬砂轮可获得良好的砂轮表面质量和高的整形效率。     

Wear mechanism of metal bond diamond wheels trued by wire electrical discharge machining

The stereographic scanning electron microscopy (SEM) imaging was used to investigate the wear mechanism in wire electrical discharge machining (EDM) truing of metal bond diamond wheels for ceramic grinding. A piece of the grinding wheel was removed after truing and grinding to enable the examination of wheel surface and measurement of diamond protrusion heights using a SEM and stereographic imaging software. The stereographic SEM imaging method was calibrated by comparing with the profilometer measurement results. On the wheel surface after wire EDM truing and before grinding, some diamond grain protruding heights were measured in the 32 μm level. Comparing to the 54 μm average size of the diamond grain, this indicated that over half of the diamond was exposed. During the wire EDM process, electrical sparks occur between the metal bond and EDM wire, which leaves the diamond protruded in the gap between the wire electrode and wheel. These protruding diamond grains with weak bond to the wheel were fractured under a light grinding condition. After heavy grinding, the diamond protrusion heights were estimated in the 5–15 μm range above the wear flat. A cavity created by grinding debris erosion wear of the wheel bond could be identified around the diamond grain.     

超硬合金剪刀片的研磨工艺研究

通过深入研究和大量的试验,对金刚石砂轮研磨超硬合金刀片方法做了新的尝试,指出了用树脂结合剂金刚石砂轮代替电镀金刚石砂轮对超硬合金剪刀片刃部曲面精研磨的可行性,并从磨床本身的精度、砂轮的轮廓形状、砂轮的静平衡、磨削深度、砂轮速度等影响加工面光洁度的诸多因素进行分析,找出了一套成熟的超硬合金剪刀片的研磨工艺,生产实践证明完全能够满足使用。     

IN SITU TRUING/DRESSING OF DIAMOND WHEEL FOR PRECISION GRINDING

An application for achieving on-machine truing/dressing and monitoring of diamond wheel is dealt with in dry grinding. A dry electrical discharge （ED） assisted truing and dressing method is adopted in preparation of diamond grinding wheels. Effective and precise truing/dressing of a diamond wheel is carried out on a CNC curve grinding machine by utilizing an ED assisted diamond dresser. The dressed wheel is monitored online by a CCD vision system. It detects the topography changes of a wheel surface. The wear condition is evaluated by analyzing the edge deviation of a wheel image. The benefits of the proposed methods are confirmed by the grinding experiments. The designed truing/dressing device has high material removal rate, low dresser wear, and hence guarantees a desired wheel surface. Real-time monitoring of the wheel profile facilitates determining the optimum dressing amount, dressing interval, and the compensation error.     

圆弧金刚石砂轮的修形及修锐技术研究

针对圆弧金刚石砂轮加工非轴对称非球面的平行磨削法中砂轮的修形精度要求较高，通常使用的水平圆弧杯状砂轮修整器很难保证加工精度的问题，提出带倾角圆弧修整器的设计方法。通过对修整器接触弧长的计算，修形延后率设计和修形补偿方法的研究及实验表明：新型圆弧修整器可满足高精度非轴对称非球面加工的要求。     

ROTARY TRUING OF VITREOUS BOND DIAMOND GRINDING WHEELS USING METAL BOND DIAMOND DISKS

Experiments on rotary truing of vitreous bond diamond grinding wheels were conducted to investigate the effects of truing speed ratio, type of diamond in the metal bond truing disks (synthetic versus natural), and diamond grit size in the grinding wheel on the wear of truing disk and on the cylindrical grinding of zirconia. Similar to G-ratio, a new parameter called D-ratio is defined to quantify the wear rate of the diamond truing disks. Experimental results show that, under the same truing condition, the truing disk with blocky, low friability synthetic diamond has a higher D-ratio than the truing disk with natural diamond. Diamond wheels trued by the disk with synthetic diamond also generate lower grinding force and rougher surface finish. High truing disk surface speed, 1.8 times higher than the surface speed of the grinding wheel, was tested and did not show any improvement in D-ratio. This study indicates that μm-scale precision form truing of the vitreous bond diamond wheel is difficult due to excess wear of the metal bond diamond truing disk.     

ROTARY TRUING OF VITREOUS BOND DIAMOND GRINDING WHEELS USING METAL BOND DIAMOND DISKS

Abstract

Experiments on rotary truing of vitreous bond diamond grinding wheels were conducted to investigate the effects of truing speed ratio, type of diamond in the metal bond truing disks (synthetic versus natural), and diamond grit size in the grinding wheel on the wear of truing disk and on the cylindrical grinding of zirconia. Similar to G-ratio, a new parameter called D-ratio is defined to quantify the wear rate of the diamond truing disks. Experimental results show that, under the same truing condition, the truing disk with blocky, low friability synthetic diamond has a higher D-ratio than the truing disk with natural diamond. Diamond wheels trued by the disk with synthetic diamond also generate lower grinding force and rougher surface finish. High truing disk surface speed, 1.8 times higher than the surface speed of the grinding wheel, was tested and did not show any improvement in D-ratio. This study indicates that μm-scale precision form truing of the vitreous bond diamond wheel is difficult due to excess wear of the metal bond diamond truing disk.     

Experimental study on fabrication and evaluation of micro pyramid-structured silicon surface using a V-tip of diamond grinding wheel

A mechanical fabrication of micro pyramid-structured silicon surface is proposed using crossed grooving with a 60° V-tip of diamond grinding wheel. It can obtain high form-accuracy, good surface quality and efficient productivity in contrast to laser machining and etching, and also assure a high aspect ratio in contrast to other mechanical processes. In order to describe its micro-structured topography, a white-light interferometer was employed, and its measured point cloud was matched using an Iterative Closest Point (ICP) algorithm. In micro grinding, a novel CNC mutual-wear truing was first developed to sharpen the wheel V-tip; then, the effects of microscopic wheel topography, silicon crystal-orientation and grinding parameter were investigated on ground micro-topography, truing ratio and material removal ratio; finally, its form-accuracy, pyramid top radius, groove tip radius, surface roughness and aspect ratio were evaluated. It is shown that better microscopic grain protrusion topography on wheel V-tip produces much larger material removal ratio and much better micro-structured topography in micro grinding, but it leads to much less truing ratio in finer GC truing. In micro grinding, silicon crystal-orientation has little effect on micro-structured topography due to diamond crystal-orientations that are randomly distributed on wheel V-tip. Although the micro pyramid-structured form error is only about 3.4 μm, its V-groove bottom and pyramidal top have very large form errors (23.1-47.9 μm) due to the sharpness of wheel V-tip and the frangibility of micro pyramid top. On increasing feed speed, its pyramid top radius decreases and its groove tip radius slightly increases, ultimately leading to an increase in aspect ratio, whereas its surface quality descends. It is concluded that the micro-pyramid arrays may be precisely patterned on silicon surface using a SD600 wheel with crossed tool paths, on-machine V-tip truing and the depth of cut in 1 μm.     

非轴对称非球面平行磨削误差补偿技术研究

针对非轴对称非球面的成形加工法柔性不足及球形砂轮加工法对工具和机械的要求太高的缺点,提出采用普通圆弧金刚石砂轮加工的平行磨削法。对于新方法加工中存在的加工误差问题,提出在非轴对称非球面加工中使用带倾角圆弧修整器及对主轴半径和副轴半径误差采用离线补偿的加工技术。通过理论分析和试验表明此方法可达到提高非轴对称非球面的加工精度的效果。