除毛刺的对策与决窍

机械加工中经常会带来各种毛刺,防止与去除工件上的毛刺极为重要,本文对毛刺的定义、产生的规律及去除的各种方法与诀窍作了较详细的介绍。     

机械零件毛刺控制及去除工艺现状

阐述近几年来机械制造领域中毛刺控制技术的研究成果及研究进展，列出了毛刺去除工艺的应用状况、新的去毛刺方法及其研究，并指出了去毛刺技术的发展方向。     

精密加工中切削参数对毛刺尺寸的影响

毛刺的产生是金属切割加工中长期存在的问题,在实际的基础上通过对精密车削中进给方向毛刺的研究,分析了切削参数对毛刺尺寸的影响,为毛刺生成的研究以及毛刺的抑制和去除做了部分基础性工作。     

非金属零件相交小孔毛刺去除工艺研究

介绍了关于非金属零件相交小孔毛刺去除工艺的研究,针对非金属零件相交小孔毛刺去除方法进行了多方面的试验,根据试验结果,在非金属零件相交小孔毛刺去除方法上开辟了一条新的途径——热能消融法,为非金属零件相交小孔毛刺去除研究提供了可借鉴的工艺.     

精密加工中切削参数对毛刺尺寸的影响

毛刺的产生是金属切削加工中长期存在的问题,在实验的基础上通过对精密车削中进给方向毛刺的研究,分析了切削参数对毛刺尺寸的影响,为毛刺生成机理的研究以及毛刺的抑制和去除做了部分基础性工作。     

浅谈冲压件去毛刺技术

冲压件在加工中产生的毛刺,不仅影响产品外观,还会影响产品性能,增加机械运转时的噪声,成为设备故障的隐患。而去毛刺的工作量很大,费用较高,有人曾作过统计:冲压加工中去毛刺的费用占产品成本的2～15％。可见去毛刺技术有较大的实际意义。为此,本文对冲压件的去毛刺技术进行粗浅探讨,提出去除毛刺的有效方法。     

水力喷射去毛刺

<正>日本“利克斯”公司新近开发出一种RX707型去毛刺专用加工设备,利用高压水力喷射原理可以去除那些历来难以去除的毛刺,特别是孔内毛刺。     

液压阀块毛刺的预防与去除

因毛刺造成液压系统的故障对系统的安全及使用都有重大影响,如何降低毛刺的生成进而减小其对系统的危害一直是学者研究的课题之一。着重介绍液压阀块毛刺的形成机理,通过实验等方法分析了加工过程中各要素对毛刺形成的影响,并提出了行之有效的方法以减少加工时毛刺的生成,并介绍了目前比较常用的毛刺去除方法。     

离开生产线去除焊管内毛刺装置的研制

由于在线去除焊管内毛刺的方法造成焊管废品率较高，质量难以保证。本文叙述了采用离线去除内毛刺的方法。经过实验分析，效果较好，产品质量符合标准要求，得到用户的好评。     

实用化振动切削技术——振动研磨去毛刺及表面光整

研制了一种振动研磨去毛刺及平面光整工艺系统.进行了振动研磨去除微小孔钻削毛刺和表面光整试验,从试验结果可以看出,该工艺方法能彻底地去除毛刺,达到表面光整的效果.     

Effects of cutting edge radius and fiber cutting angle on the cutting-induced surface damage in machining of unidirectional CFRP composite laminates

Carbon fiber reinforced polymer composite laminates are anisotropic, inhomogeneous, and mostly prepared in laminate form before undergoing the finishing operations. The edge trimming process is considered as one of the most common finishing operations in the industrial applications. However, the laminate surface is especially prone to damage in the chip formation process, and the most common damage mode is burrs. Burrs may increase cost and production time because of additional machining; they can also damage the surface integrity. Many studies have been done to address this problem, and techniques for reducing burr size in material removal process has been the focus of the research. Nonetheless, the combined effects of the cutting edge radius and the fiber cutting angle on the burr formation have seldom been conducted, which in turn restricts to find out the mechanism of burr formation. The purpose of the present paper is to study the particular mechanism that leads to burr formation in edge trimming of CFRP laminates and investigate the effects of fiber cutting angle and cutting edge radius on burr formation. The results indicate that the burrs are prone to form in the fiber cutting angle range of 0° < χ < 90° when a large cutting edge radius of the tool is used for both milling and drilling of CFRP composites.     

Prediction of burr formation during face milling using a hybrid GMDH network model with optimized cutting conditions

In this paper, a combined hybrid group method for data handling and optimization approach is introduced to predict burr types formed during face milling. The hybrid group method for data handling (hybrid GMDH) network was constructed for realizing predictive models for the machining of aluminum alloy, and differential evolution was selected for the optimization of burr formation problem resulting in finding optimal parameter for minimizing burr formation. Burr type was included as a parameter resulting in a classification scheme in which the burr type becomes the group label and it is therefore possible in the future to classify a machining process into any of these burr types. The resulting hybrid GMDH output was in agreement with experimental results, thereby validating the proposed scheme for modeling and prediction of burr formation in milling operations.     

Characterization and modeling of burr formation in micro-end milling

Mechanical micromachining is increasingly finding applications in fabrication of components in various fields, such as, biomedical devices, optics, electronics, medicine, communications and avionics. In order to ensure adequate functionality, there are stringent requirements for form and finish in case of biomedical devices like cochlear implants and metallic optics. This necessitates that the post machined surface must be burr free. To address these issues in micromachining, this paper presents results of an experimental study to investigate the influence of main process parameters i.e. speed, feed rate, depth of cut, tool diameter and number of flutes on the formation of the various types of burrs i.e. exit burrs and top burrs produced during micro-end milling operation. The experiments performed using Taguchi method shows that three types of burr formation mechanisms prevail during micro-end milling operations; these are: lateral deformation of material, bending and tearing of the chip. Also, three types of burrs were observed include: Poisson burr, rollover burr in down milling and tear burr in up milling. Further, it is observed that the depth of cut and the tool diameter are the main parameters, which influence the burr height and thickness significantly. However, the speed and the feed rate have small to negligible effect on the burr thickness and height. Besides the experimental analysis, the paper presents an analytical model to predict the burr height for exit burr. The model is built on the geometry of burr formation and the principle of continuity of work at the transition from chip formation to burr formation. Note that prediction of burr height in micro-end milling is extremely challenging due to the complex geometry of material removal and microstructural effects encountered during cutting at that length scales. The model fares well and the prediction errors range between 0.65 and 25%.     

利用脉冲激光对木制品表面抛光技术的研究

介绍了木制品表面的毛刺现象以及去除木制品表面毛刺使木制品表面抛光的重要性。利用脉冲激光对木制品表面进行抛光的技术,最后对脉冲激光使木制品表面抛光技术的发展趋势进行展望。     

Cryogenic drilling of aluminum-based printed circuit boards: a review and analysis

Abstract

An aluminum-based printed circuit board (Al-PCB) is a composite material comprising a copper layer, an insulating layer, and an aluminum base layer. In the drilling of Al-PCBs, exit burrs are formed because of the plastic deformation of the remnant aluminum under high drilling temperatures. In this work, a new method using cryogenic media is suggested to prevent exit burrs in Al-PCB drilling. The effects of cryogenic media, such as cold air, supercritical carbon dioxide solvent (scCO₂), and liquid nitrogen (LN₂), on the drilling temperature, chip removal, tool wear and exit burr formation were observed and analyzed. The Al-PCB drilling temperature could be effectively reduced when drilling with cold air, scCO₂ or LN₂. The chip removal and tool wear could be improved when drilling with cold air or LN₂. The exit burr formation when drilling with scCO₂ or LN₂ was greater than that when drilling under cooling and cold air conditions. A cold air matching composite wood backup board (MW-0.5) could effectively control the exit burr formation within 20?μm. This is the first study on the effects of three different cryogenic media on PCB drilling and is expected to provide a good reference for the cryogenic drilling of PCBs.     

Edge burr development when using a cemented carbide micro-drill: Formation and control mechanisms

To explore the mechanism of formation and methods of control of edge burr in the grinding and forming of cemented carbide micro-drill, the morphology, material composition, and the edge structure of the generated area of the edge burrs are studied. Through indentation and scratch experiments, the critical grinding depth (h_c) of grinding machining is calculated to be 0.793–1.052 μm. The grinding experiments have verified the effects of the actual grinding depth h₀ of different single abrasive particles on the edge burr and the effectiveness of the method of controlling the burr by increasing the cutting angle of the abrasive particles. The experimental results show that edge burrs are mainly concentrated on the cutting edge close to the outer cylinder of the micro-drill. When the actual grinding depth h₀ of a single abrasive particle is less than the critical grinding depth h_c, workpiece material is mainly subjected to plastic deformation removal, the length L of the edge burr along the edge direction is 10–20 μm, the width W of the burr perpendicular to the edge direction is 1–3 μm. The formation of edge burrs is mainly related to the actual grinding depth and the abrasive grain cutting angle γ of abrasive grains. With the increase of h₀, the length L of the edge burr decreases, and the width W thereto first increases, then decreases. Increasing the cutting angle of abrasive particles can control the edge burr. By changing the grinding direction of the grinding wheel, the cutting angle of the abrasive particles can be changed from an acute angle to an obtuse angle, thereby eliminating the edge burr without affecting the performance of micro-drilling.     

金属切削毛刺专家知识系统的开发

毛刺是金属切削加工中产生的常见现象。研究开发出了金属切削毛刺专家知识系统，为管理切削实验所测的毛刺数据、查询毛刺类型与尺寸、优化选择加工参数和进行切削毛刺形成的动力学仿真等奠定了基础。进而，为实现切削毛刺的预报与控制开辟了新途径。     

Burr analysis in microgrooving

Microburr formation affects badly on product's quality, especially the finishing surface. Besides, deburring techniques on microcutting are almost impossible or high cost. Understanding burr formation phenomena and minimizing burr size in correlation with cutting conditions and material properties, in this case, are more appropriate. For the purpose of exploring the burr phenomena in micrometal cutting, two cases of burr formation in grooving micropatterns are introduced in the paper. The burr happens along the cutting direction—side burr—of prism pattern, and the other happens at the exit edge of the pattern in the cutting direction—exit burr—of pyramid pattern. Besides, the exit break off which occurs during the exit burr formation is also studied. The analytical solutions for predicting the burr and break off size in each case are also proposed and compared with experiments.     

Development of intelligent system to minimize burr formation in face milling

The exit burr generated in the face milling operation at the edge of the workpiece usually requires deburring processes to enhance the level of precision of the parts. This paper is to geometrically understand the formation of the exit burr in the face milling operation on the arbitrary shaped workpiece with multiple feature such as hole, spline, and arc so that we can suggest the cutting conditions and tool path to minimize the burr formation on the given workpiece in the early design stage. The burr formation mechanism in each type of burr is classified based on the experimental results. A database is developed to store and predict burr formation results. A Windows based program is developed with the algorithm including three steps, i.e., the feature identification, the cutting condition identification, and the analysis on exit burr formation. We can predict which portion of the workpiece would have the exit burr in advance so that we can manage to find a way to minimize the exit burr formation in an actual cutting. Here, the idea of critical burr length is introduced as a criterion in optimization.