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。     

超硬磨料碟形砂轮新型修整器设计及其稳定性实验研究

介绍了一种新型的碟形超硬磨料砂轮修整器。该修整器采用SiC和金刚石磨料杯形砂轮作为修整工具可以对刚性较差的大直径碟形超硬磨料砂轮完成修形和修锐工作,并利用变频器实现修整时的无级调速以达到最佳修整效果。通过以修整力为研究对象对修整器的系统工作稳定性进行了实验研究,得出该新形修整器的工作稳定性好,可以满足超硬磨料碟形砂轮的精密修整工艺要求。     

金刚石型面约束的自由磨粒挤磨修整超硬磨料砂轮方法

针对超硬磨料砂轮存在修整困难的问题，基于金刚石和普通材料在强度上存在巨大差异的特点，提出了一种在金刚石型面约束下将磨粒挤压和修磨相结合的修整方法，其基本原理是：表面有精密形状的金刚石工具通过高速旋转生成具有约束能力的高强度型面，型面通过约束自由磨粒对被修砂轮产生挤压划擦作用破坏砂轮结合剂完成砂轮高效修形,同时通过修整工具高强度金刚石磨料的微研削作用对被修砂轮型面进行进一步精密修磨。对约束型面的形成及自由磨粒在型面约束下挤压和研削作用机制进行了分析，并介绍了挤磨修整系统的构成和特性，对修整力、修磨速度和自由磨粒等参数影响规律进行了初步试验探索，结果表明，自由磨粒型面约束下的挤压能够实现超硬磨料砂轮的快速成形精密修整。     

垂直式超硬砂轮圆弧修整器设计与砂轮修整

针对圆弧形超硬砂轮修整难度大、修整精度低的问题，对树脂结合剂圆弧形金刚石砂轮进行了精密修整研究。设计制造了一种垂直式超硬砂轮圆弧修整器，通过修整试验研究了不同粒度的圆弧形砂轮在修整前后表面粗糙度、弧形精度、圆度、表面形貌的变化情况。砂轮修整前后对氮化硅陶瓷轴承套圈沟道进行了磨削，并测量了磨削后的轴承套圈沟形精度。研究结果表明：相比修整前，修整后砂轮表面粗糙度平均值由1.731 8 μm减小至0.772 4 μm，减小了55.4%；弧形精度平均值由33.604 7 μm减小至8.527 6 μm，减小了74.6%，修整后4个砂轮的弧形精度更加稳定，且随着砂轮粒度的减小，弧形精度略有减小趋势；砂轮圆度平均值由43.721 μm减小至18.002 μm，减小了58.8%，修整使大量新的磨粒露出。所设计的垂直式超硬砂轮圆弧形修整器可对圆弧砂轮进行精密修整，可改善圆弧形砂轮的弧形精度及圆度，修整后砂轮磨削的轴承套圈沟形精度得到了大幅提高。     

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。     

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     

基于ARM的激光修整超硬磨料砂轮控制系统

针对激光修整超硬磨料砂轮的需要,设计了一种以ARM为控制核心、嵌入式Linux为操作系统的控制系统.系统通过CCD激光位移传感器实时采集超硬磨料砂轮表面的形貌信号;上位机采用LabVIEW软件对采样值进行存储分析,得出用于砂轮修整的基准信号值并回传给下位机;下位机调用应用程序完成基准信号值与采样值的比较,根据比较结果驱动声光调Q YAG激光器脉冲出光,从而实现激光对超硬磨料砂轮的选择性修整.试验结果表明,系统具有良好的实用性.     

超硬磨料砂轮激光修整试验系统的研究

设计了一套以声光调QYAG激光的连续输出光作为测量光源 ,采用光学三角测量在线检测的三维激光烧蚀精密加工系统 ,并以该系统进行超硬磨料砂轮修整试验 ,从而找到了超硬磨料砂轮激光精密修整的新方法     

超硬磨料砂轮激光修整试验系统的研究

设计了一套以声光调ＱＹＡＧ激光的连续输出光作为测量光源,采用光学三角测量在线检测的三维激光烧蚀精密加工系统,并以该系统进行超硬磨料轮修整试,从而找到了超硬磨料砂轮激光精密修整的新方法。     

金刚石砂轮的简易修整法

我厂大批量生产永磁铁氧体元件,产品需要进行磨削加工。由于该材料属于难磨材料既硬又脆。为了提高生产效率我们采用金刚石砂轮进行磨削加工。虽然金刚石砂轮比较耐用,但是金刚石砂轮也和普通砂轮一样,磨削表面会产生磨钝和凹凸不平现象。使生产效率下降,产品加工面粗糙度增大,磨削精度降低。如遇这种情况普通砂轮可以用焊有大颗粒金刚石的修整器,进行修整后继续使用。而金刚石砂轮因无法用上述方法个整,只好换上一只新的砂轮。旧砂轮丢弃一旁十分可惜。我们通过现场检查分析,认为金刚石砂轮上压铸的磨削层有3mm厚,粘结的金刚石颗粒固然非常坚硬,但是结合剂却能容易地被磨削掉,失去结合剂的金刚石颗粒会自动地脱落,暴露出     

基于修整力的树脂结合剂金刚石砂轮机械修整

研究了树脂结合剂金刚石砂轮修整过程中修整力与修整效果的关系,基于修整力的变化表征了砂轮的表面形貌及磨削性能。首先,对碳化硼、碳化硅、白刚玉3种砂轮修整工具进行实验,并采集了修整过程中修整力的变化;然后,利用白光干涉仪观测修整后砂轮的表面形貌;最后,对修整后砂轮进行磨削验证实验,得到不同修整工具修整后砂轮的磨削性能。基于上述实验,分析并验证了修整力的变化与砂轮表面形貌和砂轮磨削性能的关系。结果表明,法向力Fn能够表征砂轮的磨粒切削刃密度以及磨粒突出高度;修整比率β反映了砂轮的锋锐程度,当β稳定时,砂轮达到充分修整。因此修整力反映了砂轮表面形貌和磨削性能,根据修整力的变化可以把握砂轮的修整进程。     

On-machine precision preparation and dressing of ball-headed diamond wheel for the grinding of fused silica

In the grinding of high quality fused silica parts with complex surface or structure using ball-headed metal bonded diamond wheel with small diameter,the existing dressing methods are not suitable to dress the ball-headed diamond wheel precisely due to that they are either on-line in process dressing which may causes collision problem or without consideration for the effects of the tool setting error and electrode wear.An on-machine precision preparation and dressing method is proposed for ball-headed diamond wheel based on electrical discharge machining.By using this method the cylindrical diamond wheel with small diameter is manufactured to hemispherical-headed form.The obtained ball-headed diamond wheel is dressed after several grinding passes to recover geometrical accuracy and sharpness which is lost due to the wheel wear.A tool setting method based on high precision optical system is presented to reduce the wheel center setting error and dimension error.The effect of electrode tool wear is investigated by electrical dressing experiments,and the electrode tool wear compensation model is established based on the experimental results which show that the value of wear ratio coefficient K’ tends to be constant with the increasing of the feed length of electrode and the mean value of K’ is 0.156.Grinding experiments of fused silica are carried out on a test bench to evaluate the performance of the preparation and dressing method.The experimental results show that the surface roughness of the finished workpiece is 0.03 μm.The effect of the grinding parameter and dressing frequency on the surface roughness is investigated based on the measurement results of the surface roughness.This research provides an on-machine preparation and dressing method for ball-headed metal bonded diamond wheel used in the grinding of fused silica,which provides a solution to the tool setting method and the effect of electrode tool wear.     

砂轮修磨装置结构设计

为满足生产需要,设计了普通砂轮机的砂轮修磨器,阐述了砂轮修磨器的设计结构原理。利用车床车削原理,在砂轮机上安装一修磨装置,通过丝杆的纵向和横向传动来完成金刚笔的进给,从而完成砂轮的修整。     

GC杯型砂轮粒度与金刚石砂轮修整效率间的关系建模

在GC杯型砂轮修整金刚石砂轮修整机理以及实验的基础上,建立了GC粒度与碟形金刚石砂轮修整效率间的关系模型,通过模型的分析表明:不同粒度和浓度的金刚石砂轮应采用相应粒度的GC杯型砂轮来修整,浓度越低、粒度越小时应采用的GC颗粒越大,反之则越小。为检验模型的可靠性作了两个验证性实验,实验结果表明:该模型具有较强的实用性;100#粒度、100%浓度,200#粒度、100%浓度的树脂结合剂碟型金刚石砂轮分别采用60#和100#粒度的GC杯型砂轮修整时效率最高。最后,在模型及实验基础上分析了GC粒度与常用金刚石砂轮修整效率间的关系,并对模型的应用进行了推广。     

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.     

椭圆振动修整超声磨削ＺrＯ２温度试验研究

采用椭圆超声振动辅助金刚石笔修整方法修整金属结合剂金刚石砂轮,考察声学系统参数及磨削参数对超声振动辅助磨削纳米氧化锆陶瓷过程中磨削温度的影响.试验结果表明,椭圆超声振动辅助修整的金刚石砂轮超声振动磨削中,磨削温度相对较低.相比其他修整参数,修整深度对磨削温度的影响较小.磨削参数中,磨削深度对磨削温度影响因子较大,砂轮速度影响较弱.此外,磨粒在切削过程中做超声振动,改变了切削条件及散热条件,弱化了砂轮表面地貌对磨削温度的影响,因此,不同修整方式的金刚石砂轮的磨削温度差别不大,两种修整方式下磨削温度下降的梯度大致相当.     

A novel technique for dressing metal-bonded diamond grinding wheel with abrasive waterjet and touch truing

The dressing of metal-bonded diamond grinding wheels is difficult despite their availabilities on hard and brittle materials. In this paper, a novel compound technology that combines abrasive waterjet (AWJ) and touch truing is proposed for dressing metal-bonded diamond grinding wheel precisely and efficiently. The dressing experiments of a coarse-grained and a fine-grained bronze-bonded diamond grinding wheel were carried out on a surface grinder with a developed AWJ system. The feasibility of this method was verified by analyzing the wheel runout, the truing forces, and the wheel surface topography. The variations of 3D surface roughness of wheel surface topography during the compound dressing process were quantitatively analyzed. The mechanism of AWJ and touch compound dressing is also discussed. Further, a reaction-bonded silicon carbide block was ground to validate the dressing quality. The experiment results indicate that the grinding wheels that were well dressed by the proposed technique leads to a smaller grinding force and a smaller surface roughness than that of undressed wheels.     

The mechanism and application of bronze-bond diamond grinding wheel pulsed laser dressing based on phase explosion

This paper presents a theoretical analysis of the surface bond removal mechanism for bronze-bond diamond grinding wheels using a pulsed laser. For the first time, the existence of a phase explosion phenomenon during the process of grinding wheel laser dressing is proposed, and the negative effects of a phase explosion on laser dressing are analyzed. Additionally, a theoretical study on phase explosion is conducted. The mechanism of bronze-bond diamond grinding wheel laser dressing is improved, and theoretical guidance for bronze-bond diamond grinding wheel laser dressing is provided. In the experiment, the processing parameters of the laser during phase explosion are studied, and a grinding test under the corresponding conditions is conducted. A high-speed camera is used to observe phase explosion in the laser dressing process. An ultra-depth 3-D microscope system is used to observe the topography of the bronze-bond diamond grinding wheel after dressing and grinding as well as the bronze wheel surface quality. It is concluded that to avoid phase explosion from occurring in the laser dressing of the bronze-bond grinding wheel, chip space around the bond must exist for the abrasive particle protrusions. The processing parameters of laser dressing under certain condition are optimized, and the desired dressing effect is achieved.     

碟型金刚石砂轮修整系统稳定性分析及修整装置的改进

对杯型砂轮修整碟型金刚石砂轮的修整系统进行了稳定性分析,分析结果表明:杯形砂轮磨损刚度、碟型金刚石砂轮磨损刚度以及两砂轮间的接触刚度对修整系统稳定性的影响明显,其中两砂轮间接触刚度的影响因具有双倍效应,故最为显著;在系统稳定的前提下提高两砂轮间的接触刚度可提高修整质量和修整效率。在此理论基础上对原有专用修整装置进行了改进,从而大大提高了修整效率和修整质量。