【正文】 ical milling of pockets, contours, overall metal removal, chemical blanking for etching through thin sheets。另外，除了提供磨粒進行切削外，漿料還可對音極進行冷卻，并將切削區(qū)的磨粒和切屑帶走。超聲加工系統(tǒng)包括音極組件、超聲發(fā)生器、磨料供給系統(tǒng)及操作人員的控制。超聲加工超聲加工為日益增長的對脆性材料如單晶體、玻璃、多晶陶瓷材料的加工需求及不斷提高的工件復雜形狀和輪廓加工提供了解決手段。激光加工適用于任何可以很好地吸收激光輻射的材料，而傳統(tǒng)加工工藝必須針對不同硬度和耐磨性的材料選擇合適的刀具。由于這個原因，激光切削所產(chǎn)生的切口非常窄。由于工具和工件間沒有接觸，電化學加工是加工薄壁、易變形零件及表面容易破裂的脆性材料的首選。型腔的形狀正好是與工具相匹配的陰模的形狀。盡管利用電解作用作為金屬加工手段是近代的事，但其基本原理是法拉第定律。該工藝采用如下幾種形式：凹坑加工、輪廓加工和整體金屬去除的化學銑，在薄板上進行蝕刻的化學造型，在微電子領(lǐng)域中利用光敏抗蝕劑完成蝕刻的光化學加工(PCM)，采用弱化學試劑進行拋光或去毛刺的電化學拋光，以及利用單一化學活性噴射的化學噴射加工等。每次電火花所蝕除掉的材料量通常在105～106mm3范圍內(nèi)。相比于利用不同刀具進行金屬切削和磨削的常規(guī)加工，電火花加工更為吸引人之處在于它利用工件和電極間的一系列重復產(chǎn)生的（脈沖）離散電火花所產(chǎn)生的熱電作用，從工件表面通過電腐蝕去除掉多余的材料。在某些情況下，傳統(tǒng)加工可能行不通。注意中英文對照格式要按畢業(yè)論文格式整（字體大小、幅面、段落間距等應符合畢業(yè)論文格式要求）。傳統(tǒng)加工可以定義為利用機械（運動）能的加工方法，而特種加工利用其他形式的能量，主要有如下三種形式： ； ； 。電火花加工是利用存儲在電容器組中的電能（一般為50V/10A量級）在工具電極（陰極）和工件電極（陽極）之間的微小間隙間進行放電來去除材料的。該工藝是最古老的特種加工工藝，主要用于凹腔和輪廓加工，以及從具有高的比剛度的零件表面去除余料。10%左右。最近，還將電化學加工應用于電子工業(yè)的微加工中。泵壓后的電解液以高達5～50 m/s的速度通過間隙，將溶解后的材料、氣體和熱量帶走。由激光發(fā)射出的光能具有不同于其他光源的特點：光譜純度好、方向性好及具有高的聚焦功率密度。可以精確控制材料去除率使得激光加工成為微制造和微電子技術(shù)中非常重要的加工方法。激光打孔可以加工用其他方法難以加工的高深徑比的孔。在超聲加工中，實際切削由液體中的懸浮磨?；蛘咝D(zhuǎn)的電鍍金剛石工具來完成。換能器將電脈沖轉(zhuǎn)換成垂直沖程，垂直沖程再傳給變幅桿進行放大或壓抑。 the workpiece is too flexible or slender。10% of the material thickness can be maintained in chemical order to improve the production rate, the bulk of the workpiece should be shaped by other processes(such as by machining)prior to chemical variations can occur because of size changes in workpiece due to humidity and variation can be minimized by properly selecting etchants and controlling the environment in the part generation and the production area in the Machining(ECM)Electrochemical metal removal is one of the more useful nontraditional machining the application of electrolytic machining as a metalworking tool is relatively new, the basic principles are based on Faraday , electrochemical machining can be used to remove electrically conductive workpiece material through anodic mechanical or thermal energy is process is generally used to machine plex cavities and shapes in highstrength materials, particularly in the aerospace industry for the mass production of turbine blades, jetengine parts, and nozzles, as well as in the automotive(engines castings and gears)and medical recent applications of ECM include micromachining for the electronics machining(ECM), shown in , is a metalremoval process based on the principle of reverse this process, particles travel from the anodic material(workpiece)toward the cathodic material(machining tool).Metal removal is effected by a suitably shaped tool electrode, and the parts thus produced have the specified shape, dimensions, and surface forming is carried out so that the shape of the tool electrode is transferred onto, or duplicated in, the cavity produced is the female mating image of the tool high accuracy in shape duplication and high rates of metal removal, the process is operated at very high current densities of the order 10100 A/cm2,at relative low voltage usually from 8 to 30 V, while maintaining a very narrow machining gap(of the order of mm)by feeding the tool electrode with a feed rate from to 20 mm/ material, gas, and heat are removed from the narrow machining gap by the flow of electrolyte pumped through the gap at a high velocity(550 m/s), so the current of electrolyte fluid carries away the deplated material before it has a chance to reach the machining a nonmechanical metal removal process, ECM is capable of machining any electrically conductive material with high stock removal rates regardless of their mechanical particular, removal rate in ECM is independent of the hardness, toughness and other properties of the material being use of ECM is most warranted in the manufacturing of plexshaped parts from materials that lend themselves poorly to machining by other, above all mechanical is no need to use a tool made of a harder material than the workpiece, and there is practically no tool there is no contact between the tool and the work, ECM is the machining method of choice in the case of thinwalled, easily deformable ponents and also brittle materials likely to develop cracks in the surface Beam Machining(LBM)LASER is an acronym for Light Amplification by Stimulated Emission of the laser is used as a light amplifier in some applications, its principal use is as an optical oscillator or transducer for converting electrical energy into a highly collimated beam of optical light energy emitted by the laser has several characteristics which distinguish it from other light sources: spectral purity, directivity and high focused power machining is the material removal process acplished through laser and target material speaking, these processes include laser drilling, laser cutting, laser welding, and laser grooving, marking or machining()is localized, noncontact machining and is almost reactingforce process can remove material in very small amount and is said to remove material “atom by atom”.For this reason, the kerf in laser cutting is usually very narrow , the depth of laser drilling can be controlled to less than one micron per laser pulse and shallow permanent marks can be made with great this way material can be saved, which may be important for precious materials or for delicate structures in ability of accurate control of material removal makes laser machining an important process in microfabrication and laser cutting of sheet material with thickness less than 20mm can be fast, flexible and of high quality, and large holes or any plex contours can be efficiently made through Affected Zone(HAZ)in laser machining is relatively narrow and the resolidified layer is of micron this reason, the distortion in laser machining is can be applied to any material that can properly absorb the laser is difficult to machine hard materials or brittle materials such as ceramics using traditional methods, laser is a good choice for solving such cutting edges c