機(jī)械工程英語第二版part2unit11翻譯（參考模板）

1、傳播優(yōu)秀Word版文檔 ，希望對您有幫助，可雙擊去除！機(jī)械工程英語（第11單元） Rapid Prototyping and Manufacturing Technologies快速原型制造和快速制造技術(shù)Introduction介紹 Manufacturing community is facing two important challenging tasks：（1）Substantial reduction of production development times; and (2) Improvement on flexibility for manufacturing multi-

2、variety and small batch-size products. Computer-aided design and manufacturing (CAD and Cam) have significantly improved the traditional production design and manufacturing. However, there are a number of obstacles in true integration of computer-design with computer-aided manufacturing for rapid de

3、velopment of new products.制造社會面臨兩個重要的艱巨任務(wù)：1大幅度減少產(chǎn)品開發(fā)時間，以及改善對彈性制造多品種，小批量大小的產(chǎn)品。電腦輔助及制造大大改善了傳統(tǒng)的生產(chǎn)設(shè)計和制造。但是，有一個數(shù)字障礙計算機(jī)輔助設(shè)計與真正的一體化電腦輔助制造新產(chǎn)品的快速發(fā)展。 To substantially shorten the time for developing patterns, and prototypes, some manufacturing enterprises have started to use rapid prototypes(RP)methods for co

4、mplex patterns making and component prototyping. Over the past few years, A variety of new rapid manufacturing theologies, generally called Rapid Prototyping and 傳播優(yōu)秀Word版文檔 ，希望對您有幫助，可雙擊去除！Manufacturing ,have emerged; the technologies developed include stereo lithography(SL),selective laser sinterin

5、g (SLS), fused deposition modeling(FSM),laminated object manufacturing(LOM),and three dimensional printing (3D Printing)。These technologies are capable of directly generating physical objects from CAD databases. They have a common important feature: the prototype part is produced adding materials ra

6、ther than removing materials, that is, a part is first modeled by a geometric modeler such as a solid modeler, and then is mathematically sectioned(sliced)into a series of parallel cross-section pieces. For each piece, the curing or binding paths are generated. These curing or binding paths are dire

7、ctly used to instruct the machine for producing the part by solidifying or binding a line of material. After a layer is built, a new layer is built on the previous one in the same way. Thus, the model is built layer by layer from the bottom to top.為了大大縮短母摸、模具和樣件的制作時間，一些制作廠開始利用快速原型制造技術(shù)來制作復(fù)雜的母模和零部件的原型

8、。在過去幾年中，各種新的快速制造技術(shù)，通常被稱為快速成型與制造，有涌現(xiàn)，這些技術(shù)包括立體開發(fā)，選擇性激光燒結(jié)，熔融沉積成型，分層實體制造，三維打印。這些技術(shù)能夠直接從CAD數(shù)據(jù)庫生成實體對象。他們都有一些共同的重要特征：原型件都是通過增材制造，而不是材料去除工藝制作的，也就是說，零件首先通過幾何建模軟件，比如一個實體建模模塊來建模，然后用數(shù)學(xué)的方法進(jìn)行切層處理，使其成為一連串平行的橫截面片。傳播優(yōu)秀Word版文檔 ，希望對您有幫助，可雙擊去除！每件，固化或具有約束力的路徑生成。這些固化或具有約束力路徑是直接用于指導(dǎo)生產(chǎn)的部分機(jī)器固化或具有約束力的材料一致。建成后，一層是，一個新的層是建立在以同

9、樣的方式前一個。因此，該模型建立一層一層從底部到頂部。RR Processes RP反相進(jìn)程 As mentioned earlier, there are several technologies available for model production based on the principle of “growing” or “additive” manufacturing. The major differences among these technologies are in two aspects (1) Materials used, and (2) Part build

10、ing techniques. The following sections will explain in detail these rapid prototyping technologies with respect to the above two aspects.如前所述，有幾種技術(shù)可以為模型生產(chǎn)的基礎(chǔ)上，增加或添加劑生產(chǎn)原則。這些技術(shù)之間的主要分歧是在兩個方面;材料使用，而部分建筑技術(shù)。以下部分將解釋快速原型技術(shù)，這些細(xì)節(jié)就上述兩項方面。1.Stereo lithography光固化Stereo lithography apparatus (SLA) was invented by

11、 Charles Hull of 3D Systems Inc. It is the first commercially available rapid prototype and is considered as the most widely used prototyping machine. The material used is liquid pho-to-curable resin, acryl ate (monomers) are polymerized into large 傳播優(yōu)秀Word版文檔 ，希望對您有幫助，可雙擊去除！molecules. Based on this

12、 principle, the part is built in a vat of liquid resin as shown in Figl.1.光固化成型機(jī)由3D系統(tǒng)公司的Charles Hull 發(fā)明。它是世界第一臺使用最廣的商業(yè)快速成型機(jī)。使用的材料為丙烯酸光敏樹脂。在光子的引發(fā)下，小分子（單體）聚合成大分子。原型零件就是根據(jù)這一原理從樹脂槽中制作出來的。The SLA machine creates the prototype by tracing layer cross-section on the surfaces of the liquid photopolymer pool

13、with a laser beam. Unlike the contouring or zigzag cutter movement used in CNC machining, the beam traces in parallel lines. The laser beam is deflected horizontally in X and Y axes by galvanometer-driven mirrors so that it moves across the surface of the resin to produce a solid resin covers the so

14、lidified layer. A wiper helps appeared the viscous polymer over for building the next layer. The laser draws a new layer on the top of the previous one. In this way, the model is built layer by layer from bottom to top.蘇丹解放軍機(jī)上創(chuàng)建的跟蹤層橫截面的原型表面用激光束液體感光樹脂池。同數(shù)控機(jī)床加工時刀具的輪廓走刀和循環(huán)走刀方式不一樣，激光束是以平行方式掃描的。（4） 該激光束偏

15、轉(zhuǎn)在X和Y軸的橫向振驅(qū)動鏡子，以便它在整個行動的樹脂表面產(chǎn)生了堅實的格局。建成后1層，電梯下降一個用戶指定的距離和新的液態(tài)樹脂固化涂料覆蓋層。刮板用來將粘稠的樹脂均勻涂覆在零件表面以便于下一層的制作。激光在前一層的頂部進(jìn)行新一層的掃描。這樣，原型就自下而上地逐層制作而成。傳播優(yōu)秀Word版文檔 ，希望對您有幫助，可雙擊去除！There are several features worthy of mentioning of SLA有許多值得一提的SLA的幾個特點。1.Material. 材料。There are five commercially available photopolymers

16、. All of them are a kind of acryl ate.這五個商用光聚合物。他們都是一種丙烯酸類。(1) Support. （2）支持。 Because a model is created in liquid, the overhanging regions of the part (unsupported below) may sag or float away during the building process. The prototype thus needs some predesigned support until it is cured or solid

17、ified. These additional features are built on the model parts and have to be trimmed after the model building is completed.因為模型是在液體中創(chuàng)建了一部分（不受支持低于）懸垂地區(qū)可能驟降或漂浮在建設(shè)過程中走。因此，需要一些原型預(yù)先設(shè)計的支持，直到它被治愈或凝固。這些附加功能是建立在模型部分，要修剪后建設(shè)完成。(3)Model accuracy and performance. （3） 模型的精度和性能。 The accuracy achieved is about 0.5%

18、 .The layer thickness is between 0.004”and 0.003”.Presently,the SLA machines made by 3D Systems Inc. are the most accurate machines among the RP&M systems.精度達(dá)到約0.1的整體尺寸和體積較大的惡化，但不超過0.5。層厚度為0.03和0.004之間。目前，蘇丹解放軍機(jī)由3D系統(tǒng)公司。反相屬于機(jī)電系統(tǒng)中最精確的機(jī)器。傳播優(yōu)秀Word版文檔 ，希望對您有幫助，可雙擊去除！1. Selective laser sintering(SLS) 2。選擇

19、性激光燒結(jié)SLS uses a carbon dioxide laser to sinter successive layers of powder instead of liquid. In SLS processes, a thin layer of powder is applied by a rotating roller mechanism onto the work place. The powder material is preheated to a temperature slightly below its melting point. The laser beam tra

20、ces the cross-section on the powder surface to heat up the powder to the sintering temperature so that the powder scanned by the laser is bonded. The powder that is not scanner by the laser will remain in place to serve as the support to the next layer of powder, which aids in reducing distortion. W

21、hen a layer of the cross-section is completed, the roller levels another layer of powder over the sintered one for the next pass.Fif.11.2 shows the working principle of SLS.選擇性激光燒結(jié)采用二氧化碳激光燒結(jié)粉末，而不是連續(xù)的液體層。選擇性激光燒結(jié)過程中，一薄層粉是由地方上的工作輥旋轉(zhuǎn)機(jī)制的應(yīng)用。粉末材料預(yù)熱的溫度稍低于其熔點。激光束的痕跡跨粉末表面上的部分來加熱粉末燒結(jié)溫度，使粉末激光掃描是保稅。即不是由拉斯特掃描將繼續(xù)留

22、在當(dāng)?shù)刈鳛槲磥淼姆蹖?，減少失真艾滋病支助粉末。當(dāng)一個截面層完成后，滾筒的水平在未來通過彼此的粉末 燒結(jié)層。 Fig.11.2顯示了選擇性激光燒結(jié)的工作原理。傳播優(yōu)秀Word版文檔 ，希望對您有幫助，可雙擊去除！2. Fused deposition modeling (FDM) 3。熔融沉積建模In an FDM process as shown in Fig.11.3, a spool of thermoplastic filament feeds into a heated FDM extrusion head. The movement of the FDM head is contro

23、lled by computer. Inside the flying extrusion head, the filament is melted into liquid (1C above the melting temperature) by a resistant heater. The head traces an exact out line of each cross-section layer of the part. As the head moves horizontally in X and Y axes, the thermoplastic material is ex

24、truded out of a nozzle by a precision pump. The material solidifies in 1/10 second as it is directed onto the workplace. After one layer is finished, the extrusion head moves up a programmed distance in direction for building the next layer. Each layer is bonded to the previous layer through thermal

25、 heating.在熔融沉積在Fig.11.3建模過程中，閥芯的熱塑性長絲飼料入加熱熔融沉積造型擠出頭。對熔融沉積造型頭部運動是由電腦控制。 在高速運動的擠壓頭里，絲材被電阻加熱融化成液態(tài)（高于熔點1。C左右）。擠壓頭精確按零件截面輪廓形狀移動（從而逐層將原型零件制作出來）。 水平移動的頭在X和Y軸，熱塑性材料擠壓出一府精密泵噴嘴。固化材料在1 / 10秒，因為它是把工作場所的指示。完成后，1層，擠壓頭移動了下一層建設(shè)的一個程序在Z方向的距離。每一層粘合到上一層，通過熱供暖。3. Laminated object manufacturing (LOM) 4。分層實體制造（LOM）的傳播優(yōu)秀Wo

26、rd版文檔 ，希望對您有幫助，可雙擊去除！The LOM process produce parts from bonded paper plastic, metal or composite sheet stock. LOM machines bond a layer of sheet material to a stack of previously formed laminations, and then a laser beam follows the contour of the part cross-section generated by CAD to cut it to the

27、 required shape. The layers can be glued or welded together and the excess material of every sheet is either removed by vacuum suction or remains as next layers support.Fig.11.4 shows the working principle of LOM.洛美進(jìn)程從保稅紙塑，金屬復(fù)合板股票或親達(dá)斯部分。洛美機(jī)器結(jié)合一板層材料一疊以前形成的薄片，然后用激光束遵循的部分輪廓截面由CAD生成的刪減至所需要的形狀。該層可以膠合或焊接在

28、一起，每片材過剩是可以通過真空抽吸刪除或仍然是下一層的支持。 fig.11.4顯示奧爾姆的工作原理。4. Three-dimensional printing was developed at Massachusetts Institute of Technology. In the 3Dprinting process, a 3D model is sliced into 2D cross-section layers in a computer. A layer of powder is spread on the top of the piston, the powder barding

29、 a cylinder, and then an ink-jest printing head projects duplets of blinder material onto the powder at the place where the solidification is required according to the information from the computer model. After one layer is completed, the傳播優(yōu)秀Word版文檔 ，希望對您有幫助，可雙擊去除！ piston drops a predefined distance

30、 and a new layer of powder is spread out and selectively glued. When the whole part is completed, heat treatment is required to enhance the bonding of the glued powder, and then the unbounded powder is removed. Fig.11.5 shows the working process of 3D Printing. 5. 親切體貼的三維印刷（三維印刷）三維打印是開發(fā)的麻省理工學(xué)院。在三維印刷

31、過程中，三維模型切成二維截面層在一臺計算機(jī)。 首先在氣缸的活塞（粉末床）頂部鋪上一層粉末，然后一個噴墨打印頭根據(jù)計算機(jī)模型信息在要求固化的粉末部分表面噴上粘結(jié)材料。 完成后，1層，活塞下降一個預(yù)定義的距離和一個新的層粉分散和選擇性粘貼。當(dāng)整個部分完成，熱處理必須加強粘粉粘接，然后無界粉被刪除。 fig.11.5顯示了三維打印的工作流程。當(dāng)前的RPM的應(yīng)用Current Applications of RP&MA large number of industrial companies such as Texas Instruments, Inc. Chrysler Corporation, A

32、mp Inc. and Ford Motor Co. have benefited from applying the technologies to improve their product development in the following three aspects. 一個大型的工業(yè)企業(yè)，例如得克薩斯文書所公司，克萊斯勒公司，放大器公司,和福特汽車公司。得益于采用的技術(shù)，以改善他們在以下三個方面的產(chǎn)品開發(fā)利用策略。設(shè)計工程傳播優(yōu)秀Word版文檔 ，希望對您有幫助，可雙擊去除！1. Design engineering設(shè)計工程(1) Visualization. . （1）可視化。

33、 Conceptual models are very important in product design. The touch of the physical objects can reveal unanticipated problems and sometimes spark a better design. With RP&M, the prototype of a complex part can be built in a short time, therefore engineers can evaluate a design quickly 概念模型在產(chǎn)品設(shè)計中十分重要。

34、觸摸真實的物理實體可以暴露某些無法預(yù)料的問題，有時還會引發(fā)出更好的設(shè)計。 采用RPM的，是一個復(fù)雜的零件原型可以在很短的時間，因此工程師可以評估一個設(shè)計非常快。(2) Verification and optimization. （2）驗證和優(yōu)化。 Improving product quality is always an important issue of manufacturing. With the traditional method, developing of prototypes can be produced quickly without substantial tool

35、ing and labor cost. Consequently, the verification of design concepts becomes simple: the product quality can be improved within the limited time and with affordable cost.期完善產(chǎn)品質(zhì)量始終是制造業(yè)的重要問題。與傳統(tǒng)的方法，來驗證原型開發(fā)或優(yōu)化一出大量的工具和勞動力成本的設(shè)計。因此，設(shè)計概念驗證變得簡單：產(chǎn)品質(zhì)量可以在有限的時間內(nèi)可承受的成本提高。(3) Iteration. （3）迭代Just like the automotive industry, manufacturers often put new product models into market. With RP&M technology, it is possible to go through multiple design iterations 傳播優(yōu)秀W