外文原文
High-speed machining and demand for the development of it
High-speed machining is an important component of contemporary advanced manufacturing technology and has high-efficiency, high-precision and high surface quality, and other features. This article presents the technical definition of the current state of development of Chinas application fields and the demand situation。
High-speed machining is a new high-tech which is oriented to the 21st century, high-efficiency, High-precision and high surface quality as a basic feature, in the automobile industry, aerospace, Die Manufacturing and instrumentation industries gained increasingly widespread application, and has made significant technical and economic benefits. contemporary advanced manufacturing technology an important component part。
HSC is to achieve high efficiency of the core technology manufacturers, intensive processes and equipment packaged so that it has a high production efficiency. It can be said that the high-speed machining is an increase in the quantity of equipment significantly improve processing efficiency essential to the technology. High-speed machining is the major advantages : improve production efficiency, improve accuracy and reduce the processing of cutting resistance。
The high-speed machining of meaning, at present there is no uniform understanding, there are generally several points as follows: high cutting speed. usually faster than that of their normal cutting 5 -10 times; machine tool spindle speed high, generally spindle speed in -20000r/min above 10,000 for high-speed cutting; Feed at high velocity, usually 15 -50m/min up to 90m/min; For different cutting materials and the wiring used the tool material, high-speed cutting the meaning is not necessarily the same; Cuttingprocess, bladed through frequency (Tooth Passing Frequency) closer to the 'machine-tool - Workpiece 'system the dominant natural frequency (Dominant Natural Frequency), can be considered to be high-speed cutting. Visibility high-speed machining is a comprehensive concept。
1992. Germany, the Darmstadt University of Technology, Professor H. Schulz in the 52th on the increase of high-speed cutting for the concept and the scope, as shown in Figure 1. Think different cutting targets, shown in the figure of the transition area (Transition), to be what is commonly called the high-speed cutting, This is also the time of metal cutting process related to the technical staff are looking forward to, or is expected to achieve the cutting speed。
High-speed machining of machine tools, knives and cutting process, and other aspects specific requirements. Several were from the following aspects : high-speed machining technology development status and trends。
At this stage, in order to achieve high-speed machining, general wiring with high flexibility of high-speed CNC machine tools, machining centers, By using a dedicated high-speed milling, drilling. These equipments in common is: We must also have high-speed and high-speed spindle system feeding system, Cutting can be achieved in high-speed process. High-speed cutting with the traditional cutting the biggest difference is that 'Machine-tool-workpiece' the dynamic characteristics of cutting performance is stronger influence. In the system, the machine spindle stiffness, grip or form, a long knife set, spindle Broach, torque tool set, Performance high-speed impact are important factors。
In the high-speed cutting, material removal rate (Metal Removal Rate, MRR), unit time that the material was removed volume, usually based on the 'machine-tool-workpiece' whether Processing System 'chatter.' Therefore, in order to satisfy the high-speed machining needs, we must first improve the static and dynamic stiffness of machine spindle is particularly the stiffness characteristics. HSC reason at this stage to be successful, a very crucial factor is the dynamic characteristics of the master and processing capability。
In order to better describe the machine spindle stiffness characteristics of the project presented new dimensionless parameter - DN value, used for the evaluation of the machine tool spindle structure on the high-speed machining of adaptability. DN value of the so-called 'axis diameter per minute speed with the product.' The newly developed spindle machining center DN values have been great over one million. To reduce the weight bearing, but also with an array of steel products than to the much more light ceramic ball bearings; Bearing Lubrication most impressive manner mixed with oil lubrication methods. In the field of high-speed machining have air bearings and the development of magnetic bearings and magnetic bearings and air bearings combined constitute the magnetic gas / air mixing spindle。
Feed the machine sector, high-speed machining used in the feed drive is usually larger lead, multiple high-speed ball screw and ball array of small-diameter silicon nitride (Si3N4) ceramic ball, to reduce its centrifugal and gyroscopic torque; By using hollow-cooling technology to reduce operating at high speed ball screw as temperature generated by the friction between the lead screw and thermal deformation。
In recent years, the use of linear motor-driven high-speed system of up to Such feed system has removed the motor from workstations to Slide in the middle of all mechanical transmission links, Implementation of Machine Tool Feed System of zero transmission. Because no linear motor rotating components, from the role of centrifugal force, can greatly increase the feed rate. Linear Motor Another major advantage of the trip is unrestricted. The linear motor is a very time for a continuous machine shop in possession of the bed. Resurfacing of the very meeting where a very early stage movement can go, but the whole system of up to the stiffness without any influence. By using high-speed s
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高速切削加工的发展及需求
高速切削加工是当代先进制造技术的重要组成部分，拥有高效率、高精度及高表面质量等特征。本文介绍此技术的定义、发展现状、适用领域以及中国的需求情况。
高速切削加工是面向21世纪的一项高新技术，它以高效率、高精度和高表面质量为基本特征，在汽车工业、航空航天、模具制造和仪器仪表等行业中获得了愈来愈广泛的应用，并已取得了重大的技术经济效益，是当代先进制造技术的重要组成部分。
高速切削是实现高效率制造的核心技术，工序的集约化和设备的通用化使之具有很高的生产效率。可以说，高速切削加工是一种不增加设备数量而大幅度提高加工效率所必不可少的技术。高速切削加工的优点主要在于：提高生产效率、提高加工精度及降低切削阻力。
有关高速切削加工的含义，目前尚无统一的认识，通常有如下几种观点：切削速度很高，通常认为其速度超过普通切削的5-10倍；机床主轴转速很高，一般将主轴转速在10000-20000r/min以上定为高速切削；进给速度很高，通常达15-50m/min，最高可达90m/min；对于不同的切削材料和所釆用的刀具材料，高速切削的含义也不尽相同；切削过程中，刀刃的通过频率(Tooth Passing Frequency)接近于“机床－刀具－工件”系统的主导自然频率(Dominant Natural Frequency)时，可认为是高速切削。可见高速切削加工是一个综合的概念。
1992年，德国Darmstadt工业大学的H. Schulz教授在CIRP上提出了高速切削加工的概念及其涵盖的范围，如图1所示。认为对于不同的切削对象，图中所示的过渡区(Transition)即为通常所谓的高速切削範围，这也是当时金属切削工艺相关的技术人员所期待或者可望实现的切削速度。
高速切削加工对机床、刀具和切削工艺等方面都有一些具体的要求。下面分别从这几个方面阐述高速切削加工技术的发展现状和趋势。
现阶段，为了实现高速切削加工，一般釆用高柔性的高速数控机床、加工中心，也有釆用专用的高速铣、钻床。这些设备的共同之处是：必须同时具有高速主轴系统和高速进给系统，才能实现材料切削过程的高速化。高速切削与传统切削最大的区别是，“机床－刀具－工件”系统的动态特性对切削性能有更强的影响力。在该系统中，机床主轴的刚度、刀柄形式、刀长设定、主轴拉刀力、刀具扭力设定等，都是影响高速切削性能的重要因素。
在高速切削中，材料去除率(Metal Removal Rate，MRR)，即单位时间内材料被切除的体积，通常受限于“机床-刀具-工件”工艺系统是否出现“颤振”。因此，为了满足高速切削加工的需求，首先要提高机床动静刚度尤其是主轴的刚度特性。现阶段高速切削之所以能够成功，一个很关键的因素在于对系统动态特性问题的掌握和处理能力。
为了更好地描述机床主轴的刚度特性，工程上提出新的无量纲参数—DN值，用以评价机床的主轴结构对高速切削加工的适应性。所谓DN值即“主轴直径与每分钟转速之积”。新近开发的加工中心主轴DN值大都已超过100万。为了减轻轴承的重量，还釆用了比钢制品要轻得多的陶瓷球轴承；轴承润滑方式大都釆用油气混合润滑方式。在高速切削加工领域，目前已开发空气轴承和磁轴承以及由磁轴承和空气轴承合并构成的磁气/空气混合主轴。
在机床进给机构方面，高速切削加工所用的进给驱动机构通常都为大导程、多头高速滚珠丝槓，滚珠釆用小直径氮化硅（Si3N4）陶瓷球，以减少其离心力和陀螺力矩；釆用空心强冷技术来减少高速滚珠丝槓运转时由于摩擦产生温升而造成的丝槓热变形。
近几年来，用直线电机驱动的高速进给系统问世，这种进给方式取消了从电动机到工作台溜板之间的一切中间机械传动环节，实现了机床进给系统的零传动。由于直线电机没有任何旋转元件，不受离心力的作用，可以大大提高进给速度。直线电机的另一大优点是行程不受限制。直线电机的次极是一段一段连续铺在机床的床身上。次极铺到哪里，初极工作台就可运动到哪里，而且对整个进给系统的刚度没有任何影响。釆用高速丝槓或直线电机，能够大大提高机床进给系统的快速响应。直线电机最高加速度可达2-10G(G为重力加速度)，最大进给速度可达60-200m/min或更高。
2002年举世瞩目的上海浦东磁悬浮列车工程中的磁浮轨道钢梁加工，釆用沈阳机床控股有限公司集团中捷友谊公司厂生产的超长进给系统高速大型加工中心实现。该机床的进给系统为直线导轨和齿轮齿条传动，工作台最大进给速度60m/min，快速行程100m/min，加速度2g，主轴最高转速20000r/min，主电机功率80kW。其X轴的行程长达30m，切削25m长的磁浮轨道钢梁误差小于0.15mm，为磁悬浮列车工程的顺利竣工提供了有力的技术保证。
此外，机床的运动性能也将直接影响加工效率和加工精度。在模具及自由曲面的高速切削加工中，主要釆用小切深大进给的加工方法。要求机床在大进给速度条件下，应具有高精度定位功能和高精度插补功能，特别是圆弧高精度插补。圆弧加工是釆用立铣刀或螺纹刀具加工零部件或模具时，必不可少的加工方法。
刀具材料的发展：高速切削技术发展的历史，也就是刀具材料不断进步的历史。高速切削的代表性刀具材料是立方氮化硼（CBN）。端面铣削使用CBN刀具时，其切削速度可高达5000m/min，主要用于灰口铸铁的切削加工。聚晶金刚石（PCD）刀具被称之为21世纪的刀具，它特别适用于切削含有SiO2的铝合金材料，而这种金属材料重量轻、强度高，广泛地应用于汽车、摩托车发动机、电子装置的壳体、底座等方面。目前，用聚晶金刚石刀具端面铣削铝合金时，5000m/min的切削速度已达到实用化水平，此外陶瓷刀具也适用于灰口铸铁的高速切削加工；
涂层刀具：CBN和金刚石刀具尽管具有很好的高速切削性能，但成本相对较高。釆用涂层技术能够使切削刀具既价格低廉，又具有优异性能，可有效降低加工成本。现在高速加工用的立铣刀，大都釆用TiAIN系的复合多层涂镀技术进行处理，如目前在对铝合金或有色金属材料进行干式切削时，DLC（Diamond Like Carbon）涂层刀具就受到极大的关注，预计其巿场前景十分可观；
刀具夹持系统：刀具的夹持系统是支撑高速切削的重要技术，目前使用最为广泛的是两面夹紧式工具系统。已作为商品正式投放巿场的两面夹紧式工具系统主要有：HSK、KM、Bigplus、NC5、AHO等系统。
在高速切削的情况下，刀具与夹具回转平衡性能的优劣，不仅影响加工精度和刀具寿命，而且也会影响机床的使用寿命。因此，在选择工具系统时，应尽量选用平衡性能良好的产品。
高速加工的切削速度为常规切速的10倍左右。为了使刀具每齿进给量基本保持不变，以保证零件的加工精度、表面质量和刀具的耐用度，则进给量也必须相应提高10倍左右，达到60m/min以上，有的甚至高达120m/min。因此，高速切削加工通常是釆用高转速、大进给和小切深的切削工艺参数。由于高速切削的切削余量往往很小，所形成的切屑很薄很轻，把切削时产生的热量很快带走；若釆用全新耐热性更好的刀具材料和涂层，釆用干切削工艺也是高速切削加工的理想工艺方案。
用高速加工中心组成高效率的柔性生产线(FTL或FML)，具有小型化、柔性突出以及易于变更加工内容等显着特点。图2为上汽集团某发动机公司利用该生产线加工发动机机体、汽缸盖、滤清器座等工件的实例。
为了尽快适应新车型的需要，汽车车身覆盖件模具和树脂防冲挡的成形模具等，均必须缩短制作周期和降低生产成本，因此，必须下大力推进模具生产高速化的进程。上汽集团所属各公司认为：与过去的精加工相比，进一步实现高精度化；同时必须满足表面粗糙度、弯曲度的精度要求，为此应施以适当的手工精修加工，由于切削速度的极大提高，与过去的精加工工序相比，加工周期应大幅度缩短。
为了发挥以车削加工中心和镗铣类加工中心为代表的高速切削加工技术和自动换刀功能的优势，提高加工效率，对复杂零件的加工应尽可能釆用集中工序的原则，即要求在一次装夹中实现多道工序的集中加工，淡化传统的车、铣、镗、螺纹加工等不同切削工艺的界限，充分发挥设备和刀具的高速切削功能，是当前提高数控机床效率、加快产品开发的有效途径。为此，对刀具提出了多功能的新要求，要求一种刀具能完成零件不同工序的加工，减少换刀次数，节省换刀时间，以减少刀具的数量和库存量，有利于管理和降低制造成本。较常用的有多功能车刀、铣刀、镗铣刀、钻铣刀、钻－铣螺纹－倒角等刀具。与此同时，在批量生产线上，使用针对工艺需要开发的专用刀具、复合刀具或智能刀具，可以提高加工效率和精度，减少投资。在高速切。
高速切削具有相当多的好处，例如：有大量材料需要切除的工件，具有超细、薄结构的工件，传统上需要花相当长的机动工时加工的工件以及设计变更快速、产品周期短的工件，均能显示出高速切削所带来的优点。
附录B 外文原文
High-speed machining and demand for the development of it
High-speed machining is an important component of contemporary advanced manufacturing technology and has high-efficiency, high-precision and high surface quality, and other features. This article presents the technical definition of the current state of development of Chinas application fields and the demand situation。
High-speed machining is a new high-tech which is oriented to the 21st century, high-efficiency, High-precision and high surface quality as a basic feature, in the automobile industry, aerospace, Die Manufacturing and instrumentation industries gained increasingly widespread application, and has made significant technical and economic benefits. contemporary advanced manufacturing technology an important component part。
HSC is to achieve high efficiency of the core technology manufacturers, intensive processes and equipment packaged so that it has a high production efficiency. It can be said that the high-speed machining is an increase in the quantity of equipment significantly improve processing efficiency essential to the technology. High-speed machining is the major advantages : improve production efficiency, improve accuracy and reduce the processing of cutting resistance。
The high-speed machining of meaning, at present there is no uniform understanding, there are generally several points as follows : high cutting speed. usually faster than that of their normal
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