金属切削毛刺形成与控制技术研究进展

本文系统概述了国内外对于毛刺形成机理及控制技术的研究进展,重点阐述了预测毛刺形成的解析模型和有限元模型、毛刺形成过程的实验研究以及控制毛刺形成的加工工艺和非标刀具,分析了亟待解决的问题,指出了金属切削毛刺形成机理和控制技术研究的方向.     

微细切削毛刺发展研究

微细切削加工中形成的毛刺严重降低了被加工微型零部件的精度和棱边质量,影响了工件的使用性能,对微细切削的毛刺研究有利于推动微细切削技术的发展。系统概述了国内外微细切削毛刺的研究进展,重点阐述了研究者对微细切削毛刺形成机理、影响因素及预测预报技术的研究,并在分析微细切削特殊切削环境的基础上,结合尺度效应理论研究了微细切削毛刺的形成机理,指出了微细切削毛刺研究尚存的主要问题,同时确立了今后深入开展微细切削毛刺研究的发展方向。     

微铣削加工机理研究新进展

微铣削加工技术在制造航空航天等领域所用的三维复杂微结构零件方面具有明显优势,而微铣削在加工机理、对表面质量要求等诸多方面都与常规铣削有着明显不同,因此非常有必要对微铣削加工机理进行研究。主要从切削刃钝圆半径引起的尺寸效应机制、刀具径跳对微铣削加工的影响机理、加工中毛刺形成机理以及加工中表面形成机理这四个方面对微铣削加工机理进行综述,介绍每个方面相对于常规铣削的不同,并重点分析切削刃钝圆半径的尺寸效应和微刀具径跳的产生原因、危害及研究现状,以及从仿真和试验两个方面对微铣削中毛刺形成过程和表面形成过程进行总结,对影响因素进行分析,并提出抑制毛刺的一些方法。探讨微铣削加工机理研究仍需注重解决的问题,为其后续发展方向提出一些建议。     

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。     

滚切小模数蜗轮时毛刺生成机理与控制

<正> 机械工业的迅速发展势必对切削加工的精度要求越来越高。那种认为切削毛刺的影响可以忽略不计的传统认识无疑与当代机械工业的发展不相适应。要提高切削效率,确保加工精度,降低零件的加工费用,迫切需要研究切削毛刺生成机理及生成过程中所产生的各种现象,采取有效措施,控制切削毛刺生成。本文结合我厂的经验,浅析小模数蜗轮加工中切削毛刺的生成机理与控制措施。     

少无毛刺切削技术的研究进展

在系统概述国内外少无毛刺切削加工技术研究进展的基础上,根据机械加工实际需要,给出了主动控制或减小金属切削毛刺的基本原则,探索出少无毛刺的主要途径。此外,分析了几种切削加工技术的具体应用。指出了目前尚需解决的一些主要问题,确立了今后深入开展金属切削毛刺研究的方向。     

液压阀加工中抑制毛棘生成的几种途径

本文介绍了金属切削加工中毛刺的定义和分类，并主要从零件设计、工艺路线、加工方法及刀具应用等方面阐述了抑制毛刺生成的基本思路和具体措施。     

钻削加工产生毛刺的规律研究

金属钻削加工过程中会形成一些毛刺,这些毛刺往往存在于工件过渡位置或内侧边缘,一般表现为毛边或尖角等不规则的形状。出现的毛刺使产品加工的表面粗糙度精度、配合精度、尺寸精度等受到严重影响。通常应额外地执行毛刺去除工艺,这增加了加工成本,延长了生产周期,不利于自动化加工技术的进步和发展。钻削加工孔口毛刺相对较小,一般采用孔口倒角的方式可去除毛刺;孔出口处的毛刺较大,一般在阀体内部形成交叉孔毛刺,毛刺的去除难度较大。影响钻削加工产生毛刺的因素复杂,毛刺的形成以及控制问题属于当今金属切削难以有效解决的问题和难点。为了探究钻削加工产生毛刺的规律,分析钻削加工产生毛刺的试验因素及水平,采用正交试验研究钻削加工出口毛刺的影响因素,找出影响钻削加工出口毛刺的主要因素,然后得出试验钻头钻削出口毛刺最小的工艺方案组合。结果表明,影响钻削加工产生毛刺都的因素为：进给量、冷却方式、切削速度。为此,文章就钻削加工中毛刺的形成规律以及处理的对策发表了一些浅显的认识,旨在为毛刺规避和去除工艺的应用带来技术、理论支撑。     

铣削毛刺的形成及其控制

铣削加工是金属切削加工的主要方法之一,端铣是铣削加工中经常选用的加工方式。本文系统地阐述了影响端铣毛刺形成的主要因素,并从结构设计到制造加工全过程出发,探讨了减小和控制端铣毛刺的技术、工艺和方法。     

金属切削毛刺数据库系统的设计

毛刺的产生和存在是金属切削加工中普遍存在的问题 ,它直接影响了工件的加工精度及质量。基于数据库和Java ,研究了金属切削毛刺数据库系统的设计 ,实现了切削毛刺数据的管理、切削毛刺类型与尺寸大小及加工参数的查询 ,进一步丰富和完善了金属切削毛刺的预报与控制理论。     

二维切削中切削方向毛刺与亏缺的界限转换条件

建立了二维切削中切削方向毛刺与亏的生成模型,给出了切削方向毛刺与亏缺的判别准则,并对影响切削方向毛刺与亏缺转换的主要因素进行了实验研究和相应的理论分析,提示出切削方向毛刺与亏缺的界限转换条件为：剪切应变ε≤3,为亏缺;3＜ε＜4,为过渡区;ε＞4,为毛刺。并且,切削方向毛刺与亏缺的界限转换条件因切削条件变化而变化。为进一步深入研究切削毛刺的生成与抑制理论提供了科学的基础。     

切削参数对微铣毛刺尺寸影响的试验研究

以铝合金Al6061-T6为研究对象,采用单因素试验方法,利用MIKRON UCP800五轴联动加工中心进行了微铣槽试验,研究了主轴转速、切削深度和进给速度对顶部毛刺尺寸的影响,初步揭示了上述切削参数对顶部毛刺尺寸的影响规律,为主动控制微铣加工过程中的毛刺尺寸提供依据。     

Experimental investigations of sideward burr formation in rotary machining

Burrs can be formed on the feed mark ridges and the edges of the machined parts in machining operations. These burrs are undesirable in terms of the surface quality, the precise dimensioning of the machined parts and the safety of operators. This paper demonstrates the effectiveness of using a rotary tool on minimizing the sideward burr formation in machining. In particular, the experimental relationships between the size of sideward burr and the cutting parameters (including tooling mechanism) are established first in rotary machining. Methods to control the size of sideward burr are then explained. The possible application of a rotary tool for deburring operations while engaged in machining is also explored.     

Analysis of precision deburring using a laser —An experimental study and FEM simulation

The purpose of this study is to develop an effective methods for automated deburring of precision components. A high power laser is proposed as a deburring tool for complex part edges and burrs. For the laser experiments, rectangular-shaped carbon steel and stainless steel machined specimens with burr along one side were prepared. A 1500 Watts CO₂ laser was used to remove burrs on the workpieces. The prediction of the heat affected zone (HAZ) and cutting profile of laser-deburred parts using finite element method is presented and compared with the experimental results. This study shows that the finite element method (FEM) analysis can effectively predict the thermal affected zone of the material and that the technique can be applied to precision components.     

Fabrication of PCD micro cutting tool and experimental investigation on machining of copper grating

This paper presents an investigation on machining of copper grating. Ultra-hard polycrystalline diamond (PCD) micro cutting tools were designed and machined, especially focused on fabricating micro channel arrays characterized by excellent quality with high efficiency. Micro cutting experiments of copper grating were carried out using the self-developed PCD micro tools, and the effect of width of cut, feed per tooth, and spindle speed on dimensional accuracy and burr formation was investigated. Additionally, optimum combination of processing parameters was obtained. As a result, a complete copper grating with superior dimensional accuracy and minimum top burrs was machined by employing the self-developed micro cutting tools under the optimal parameters.     

A study on deburring of magnesium alloy plate by magnetic abrasive polishing

Drilling is one of the most important machining operations in manufacture process. When drilling process is applied, unexpected burrs will be formed on the surface of workpiece. Even a small burr can cause unwanted problems, resulting in low quality products. In order to get better drilled parts, it is very important to know characteristics of burr formation and to remove the burr from the drilled surface with machining process. In this study, magnetic abrasive polishing (MAP) was used to research the deburring factors of magnesium alloy. Moreover, design of experiments was performed to evaluate parameters’ effect on the MAP process. As a result, it was seen that the MAP was useful to remove the burrs on the workpiece without damage from its original surface.     

The use of ultrasonic cavitation peening to improve micro-burr-free surfaces

Advances in machining technology, particularly in the field of micro-machining, have led to the design and creation of miniature components suitable for use in the precision engineering industry. However, the need to contain ubiquitous burrs still exists and has to be addressed. Previous studies on deburring have mostly focused on the parametric investigations of orientation, temperature, type of liquid media and abrasives, frequency, deburring time and power. It is hypothesized that by inducing compressive residual stresses on a pre-machined workpiece surface, the resulting burrs caused by machining can be minimized or even eliminated. The paper presents the findings of an investigative study into the possibility of inducing compressive residual stresses on machined surfaces by the use of ultrasonic cavitation, with the aim of reducing or eliminating burr formation. The paper also briefly reviews the development of ultrasonic cavitation and covers published work on deburring by ultrasonic cavitation. Experimental results are presented on the performance of ultrasonic cavitation peening on the residual stress in Stavax stainless steels and on micro-burr formation.     

Deburring of burrs in spring collets by abrasive flow machining

Micro burrs occurring inside the small and large diameters adversely affect the properties of products. Manual deburring of micro burrs in particular damages the processed surface and reduces production efficiency. In this study, spring collets made of chrome-molybdenum are used to test the deburring of the surface of collets including crossed micro grooves by abrasive flow machining. This revised version was published online in October 2004 with a correction to the issue number.     

Modeling of burr thickness in milling of ductile materials

Accuracy and surface finish play an important role in modern industry. The presence of undesired projections of materials, known as burrs, negatively affect the part quality and assembly process. To remove burrs, a secondary operation known as deburring is required for the post-processing and edge finishing of machined parts. The thickness of the burr is of interest as it describes the time and method necessary for deburring of the machined part. Burr thickness (B _t) measurements are costly and non-value-added operations that in most cases require the use of a scanning electron microscope for accurate burr characterization. Therefore, to avoid such expenses, the implementation of alternative methods for predicting the burr thickness is strongly recommended. In this research work, an analytical model for predicting the burr thickness in end milling of ductile materials is presented. 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 that also takes into account the cutting force influence on burr formation. A very good correlation was found between the modeled and experimental B _t values. The model has shown a great sensitivity to material properties such as yield strength and specific cutting force coefficient (K _c). In addition, the sensitivity of the proposed model to the feed per tooth (f _t) and depth of cut (a _p) was considerably high. The proposed model allows the prediction of the thickness of the exit up milling side burr, without the need for experimental measurement and/or approximation of shear angle (Φ), friction angle (λ), and the tool chip contact length (L), unlike existing analytical burr size prediction models. Besides analytical modeling, statistical analysis is performed on experimental results in order to distinguish dominant process parameters on B _t. It is observed that the depth of cut and feed per tooth are the main parameters which significantly affect the B _t, while the speed has only a negligible effect on it.     

磁流变光整加工技术研究进展

介绍了近年来磁流变光整加工（MRF）技术的研究状况及最新进展,对磁流变光整加工机理研究、加工机床与相关装置的开发、加工工艺试验研究、加工算法与模型研究、磁流变液流体开发与应用等五个方面进行了详细的综述与分析。最后探讨了磁流变光整加工中的关键技术与存在的问题,并对其发展趋势进行了展望。