快速成型制造的介绍及外文翻译

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快速成型制造的介绍及外文翻译

快速成型制造的介绍及外文翻译

山东英才学院毕业设计(论文)外文资料翻译学院机械制造及自动化学院专业机械设计制造及其自动化学生姓名韩俊龙班级学号2008级本科二班200801010109外文出处附件:1.外文资料翻译译文;2.外文原文快速成型制造的介绍快速成型这个术语是对于不通过机器和工具的三维造型生产而产生的一种新的相关的表示.通过快速生产的准确能力,用电脑设计系统帮助切实的造型的设计生产,第一个快速成型的系统于1988年在美国的市场内被引进并且给工程师一个通过CAD 来设计三维实物的机会且成功的生产出复杂表面的模型.使用这项技术的操作优势如下: 固态模型的高速产生.这个模型的复杂性对于生产不能形成任何的限制.最早使用这些模型是用来帮助设计者决定形状和适当性.它也能提供给预期的顾客展示三维实物的销售群,这将远远优于那些很多人发现很难去解释的传统直角作图:1.一小部分传统方法的价值是把准确的物理模型转化成三维影象.2.改进设计的讯息帮助删除设计的错误.3.对于新的产品减短上市的时间.4.自从原形相比做图更能被理解后它就能作为一种强有力的工具.5.这技术的发展到达了入许多传统领域,吸引技巧和知识导致了直接地和间接地使用作为样式和模型的三维对象为软的工具模型。

6.模型的生产是通过用机器制造有一定数量的限制。

7.在成形期间被除去的材料是难回收的。

8.用机器制造以钻井转动的碾碎的火花电蚀等的形式。

由它可能导致的形状限制。

9.在设计变动情形下,常规凿出的装饰例如样式,核心装箱,模子,夹具等。

变得昂贵而难变更,并且在许多情况下,可以要求完全再制造。

快速成型法是不同于以通过增加物质层数的常规制造方法,直到达到所期望的锐利程度,立刻减少或避免材料的损失层数。

RP&M能做什么?为开发的样式、模子和原型去极大地缩短时间。

一些制造业企业开始对于一些复杂部件的制造和成型的成分使用快速成型的方法。

在过去几年,各种各样新的迅速制造业技术,通常称为快速成型和制造(RP&M),已经涌现了;被开发的技术包括立体声石版印刷(SL),所选择的激光焊接(SLS),合并的证言塑造(FDM),薄片叠成物体的制造业(LOM),和3D打印(3D Print)。

快速成型( Rapid Prototyping )

快速成型( Rapid Prototyping )

成型示意图:
二、熔融挤出成型工艺的工作原理三、FDM机台的具体操作
• 1.开机及初始化 • 2.载入模型及调整 • 3.分层参数设置 • 4.开始加工
STL模型检验和修复
• 校验点数:点数越多,修复的正确率越高, 但时间更长,一般设定为5就足够。
测量和修改
• • • • • 单击鼠标左键——拾取面片 按住CTRL键,单击鼠标左键——拾取边 按住SHIFT键,单击鼠标左键——拾取顶点 表面反向——修复法向错误 删除表面——删除多余表面,将与该面片相连通 的所有面片都删除 • 删除面片——删除该面片 • 隐藏表面——隐藏表面,以便测量或者修改 • 设定为成型方向——以该面片为底平面,重新摆 放三维模型。
分层参数详解
• • • • • • • • • • • • • • • • • 包括三个部分:分层、路径、支撑 层厚:单层厚度。 起点:开始分层的高度,一般应为零 终点:分层结束的高度,一般为模型的最高点 轮廓线宽:层片上轮廓的扫描线宽度,一般为:1.3~1.6倍的喷嘴直径 扫描次数:层片轮廓的扫描次数 填充线宽:层片填充线的宽度。 填充间隔:相邻填充线间隔(n-1)个填充线宽 填充角度:每层填充线的方向,可输入六个值,每层依次循环 填充偏置:每层填充线的偏置数,可输入六个值 水平角度:设定能够进行孔隙填充的表面的最小角度(与水平面的夹角),该值越小, 标准填充的面积越小,若过小,会在表面形成孔隙 表面层数:设定水平表面的填充厚度,n个层厚 支撑角度:设定需要支撑的表面的最大角度(与水平面),角度越大,支撑面越大 支撑线宽:支撑扫描线的宽度 支撑间隔:与填充间隔意义类似 最小面积:需要支撑的表面的最小面积 表面层数:靠近原型的支撑部分,为使原型表面质量较高,需采用标准填充

快速成型技术的综述

快速成型技术的综述

快速成型技术的综述概要:快速成型技术又称快速原型制造(Rapid Prototyping Manufacturing,简称RPM)技术,被认为是近20年来制造领域的一个重大成果。

不断提高RP技术的应用水平是推动RP技术发展的重要方面。

并且随着这一技术本身的发展,其应用领域将不断拓展。

关键词:引言:随着全球市场一体化的形成,制造业的竞争十分激烈,产品的开发速度日益成为主要矛盾。

制造业为满足日益变化的用户需求,要求制造技术有较强的灵活性,能够以小批量甚至单件生产而不增加产品的成本。

因此,产品的开发速度和制造技术的柔性就十分关键。

从技术发展角度看,计算机科学、CAD技术、材料科学、激光技术的发展和普及为新的制造技术的产生奠定了技术物质基础。

一.RP技术的定义快速成型技术是集机械工程、CAD、逆向工程技术、分层制造技术、数控技术、材料科学、激光技术于一身,可以自动、直接、快速、精确地将设计思想转变为具有一定功能的原型或直接制造零件,从而为零件原型制作、新设计思想的校验等方面提供了一种高效低成本的实现手段。

即,快速成形技术就是利用三维CAD的数据,通过快速成型机,将一层层的材料堆积成实体原型。

二.RP技术的基本原理快速成形技术是在计算机控制下,基于离散、堆积的原理采用不同方法堆积材料,最终完成零件的成形与制造的技术。

1、从成形角度看,零件可视为“点”或“面”的叠加。

从CAD电子模型中离散得到“点”或“面”的几何信息,再与成形工艺参数信息结合,控制材料有规律、精确地由点到面,由面到体地堆积零件。

2、从制造角度看,它根据CAD造型生成零件三维几何信息,控制多维系统,通过激光束或其他方法将材料逐层堆积而形成原型或零件。

三.特点(1) 制造原型所用的材料不限,各种金属和非金属材料均可使用;(2) 原型的复制性、互换性高;(3) 制造工艺与制造原型的几何形状无关,在加工复杂曲面时更显优越;(4) 加工周期短,成本低,成本与产品复杂程度无关,一般制造费用降低50%,加工周期节约70%以上;(5) 高度技术集成,可实现了设计制造一体化;三.类型3D打印技术是一系列快速原型成型技术的统称,其基本原理都是叠层制造,由快速原型机在X-Y平面内通过扫描形式形成工件的截面形状,而在Z坐标间断地作层面厚度的位移,最终形成三维制件。

快速成型技术

快速成型技术

知识创造未来
快速成型技术
快速成型技术(Rapid Prototyping,RP)是一种快速制造技术,又称为3D打印技术。

它利用计算机辅助设计(CAD)文件为基础,通过逐层堆积材料以构建三维实体模型。

快速成型技术的原理是将CAD文件切割为一系列薄片,并逐层堆积材料形成实体模型。

常用的堆积方式包括层叠堆积、液体固化和粉末烧结等。

材料可以是塑料、金属、陶瓷等。

快速成型技术具有快速、灵活、低成本等优点。

它可以迅速制造出产品的样品,帮助设计师进行实物验证和功能测试。

同时,快速成型技术也可以用于批量生产少量产品或个性化定制产品。

目前,快速成型技术已广泛应用于各个领域,包括汽车、航空航天、医疗器械、消费品等。

它在产品开发和制造过程中起到了重要的作用,提高了设计效率和产品质量,同时缩短了产品上市时间。

1。

快速成型技术简介

快速成型技术简介

立体光固化成形(SLA)
• 是目前最为成熟和广泛应用的一种快速成型制造 工艺。这种工艺以液态光敏树脂为原材料,在计 算机控制下的紫外激光按预定零件各分层截面的 轮廓轨迹对液态树脂逐点扫描,使被扫描区的树 脂薄层产生光聚合(固化)反应,从而形成零件的 一个薄层截面。完成一个扫描区域的液态光敏树 脂固化层后,工作台下降一个层厚,使固化好的 树脂表面再敷上一层新的液态树脂然后重复扫描、 固化,新固化的一层牢固地粘接在一层上,如此 反复直至完成整个零件的固化成型。
• LOM工艺是将单面涂有热溶胶的纸片通过 加热辊加热粘接在一起,位于上方的激光 切割器按照CAD分层模型所获数据,用激 光束将纸切割成所制零件的内外轮廓,然 后新的一层纸再叠加在上面,通过热压装 置和下面已切割层粘合在一起,激光束再 次切割,如此反复逐层切割、粘合、切 割……直至整个模型制作完成 。
• 是通过将丝状材料如热塑性塑料、蜡或金 属的熔丝从加热的喷嘴挤出,按照零件每 一层的预定轨迹,以固定的速率进行熔体 沉积。每完成一层,工作台下降一个层厚 进行迭加沉积新的一层,如此反复最终实 现零件的沉积成型。
(5)三维印刷法(3DP,Three Dimensional Printing )
• 利用喷墨打印头逐点喷射粘合剂来粘结粉 末材料的方法制造原型。3DP的成型过程与 SLS相似,只是将SLS中的激光变成喷墨打 印机喷射结合剂。
成型过程示意图
• 快速成型工艺的优势:
------使模型或模具的制造时间缩短数倍甚至数十倍,大大缩 短新产品研制周期; ------使复杂模型的直接制造成为可能,提高了制造复杂零件 的能力; ------可以及时发现产品设计的错误,做到早找错、早更改, 避免更改后续工序所造成的大量损失,显著提高新产品 投产的一次成功率; ------使设计、交流和评估更加形象化,使新产品设计、样品 制造、市场定货、生产准备、等工作能并行进行,支持 同步(并行)工程的实施; ------节省了大量的开模费用,成倍降低新产品研发成本。

Prototype Introduction 快速成型技术简介

Prototype Introduction 快速成型技术简介

• 三维喷涂粘结(Three Dimensional Printing and Gluing, 3DPG)
• 焊接成型(Welding Forming) • 数码累积造型(Digital-Brick Laying) • 光掩膜法(Solid Ground Curing, SGC,也称立体光刻)、直接殼法(Direct Shell Production Casting, DSPC)、直接烧结技术、热致聚合、全息干涉制造、模型熔制、 弹道微粒制造、光束干涉固化
真空注型机使用用途
• 少量多品种产品(试制产品)的生产 • 电气电子配件的灌封工作 • 各种工业用的含浸及成型工作 • 硅橡胶及液状树脂的脱泡 /注型工作 • 各种模型产品的制作
• 蜡型铸造(精密铸造)工作
Rapid Tooling 快速模具
真空注型机技术参数:
• 一般工作时间: 1-4小时/件 • 一般每模工作寿命: 10-20件 • 标准复制精度: ± 0.2%(重复复制精度±0.1%) • 浇注样件厚度: 最小 0.5mm,最佳为1.5 mm-5 mm • 样件尺寸范围: 不同机型各有不同 • 浇注材料特性: 浇注材料为双组份聚氨酯
Rapid Prototype 快速成型
快速成型制造技术的基本原理: 采用分层累加法,即用CAD造型、生成STL文件、分层 切片等步骤进行数据处理,借助计算机控制的成型机完成材 料的形体制造.
Rapid Prototype 快速成型
Rapid Prototype 快速成型
快速成型的特点: (1)快速性 通过STL格式文件,RPM系统,几乎可以与所有的CAD造型系 统无缝连接,从CAD模型到完成原型制作通常只需几小时到几十 小时,可实现产品开发的快速闭环反馈。

外文翻译-快速成型

外文翻译-快速成型

外文翻译-快速成型河南理工大学本科毕业设计(论文)外文资料翻译题目:Rapid Prototyping快速成型学院: 机械与动力工程学院专业: 机械设计制造及其自动化班级: 机制专升本05-1姓名: 孙泽章学号: 0503050126指导老师:焦锋Rapid Prototyping1 Rapid Prototyping basic conceptRapid Prototyping is a general term applied to a family of fabrication technologies that allow engineering of solids parts to be madein minimum lead time. The common feature of the rapid prototyping processes is that they fabricate the part directly from the CAD geometric model. This is usually done by dividing the solid object into a series of small thickness and then defining the area shapes of each layer. For example, a vertical cone would be divided into a series of circular layers, each circle becoming smaller and smaller as the vertex of the cone is approached. The rapid prototyping processes then fabricate the object at the base and building each layer on top of the preceding layer to approximate the solid shape. The fidelity of the approximation depends on the thickness of each layer. As layer thickness decreases, accuracy increases. There are a variety of layer-building processes used in rapid prototyping. The most common process, called stereo lithography, uses a photosensitive liquid polymer that cures when subjected to intense light. Curing of the polymer is accomplished using a moving laser beam whose path layer is controlled by means of the CAD model. By hardening each layer, one on top of the preceding, a solid polymer prototype of the part built.Virtual prototyping, based on virtual reality technology, involves the use of the CAD geometric model to construct a digital mock-up of the product, enabling the designer and other to obtain the sensation of the real physical product without actually building the physical prototype. Virtual prototyping has been used in the automotive industry to evaluate new car style designs. The observer of the virtual prototype is able toasses the appearance of the new design even though no physical model is on display. Other applications of virtual prototyping include checking the feasibility of assembly operations, for example, parts matting, access and clearance of parts during assembly, and assembly sequence.Automated Drafting The fourth area where CAD isuseful is presentation and documentation. CAD systems can be used as automated drafting machines to prepare highly accurate engineering drawings quick. It is estimated that a CAD system increases productivity in the drafting function about fivefold over manual preparation of drawingsCAD System HardwareThe hardware for a typical CAD system consists of the following components; 1 one or more design workstations; 2 digital computer; 3 plotters, and other output devices, and 4 storage devices. The relationship among the components is illustrated in Fig. 18.5. In addition, the CAD system would have a communication interface to permit transmission of date to and from other computer systems, thus enabling some of the benefits of computer integration.Design Workstations. The workstation is the interface between computer and user in the CAD system. Its functions are the following: 1 communicate with the CPU; 2 continuously generate a graphic image; 3 provide digital descriptions of the image” 4 translate user commands into operating functions; and 5 facilitate interaction between the user andthe system The design of the CAD workstation and its available features have an important influence on the convenience, productivity, and quality of the user’s output. The workstation must include a graphics display terminal and a set of user input devices. The display terminal must be capable of showing both graphics and alphanumeric text. It is the principal means by which the system communicates with the user. For optimum graphics display, the monitor should have a large color screen with high resolution.The user input devices permit the operator to communicate with the system. To operate the CAD system, the user must be able to accomplish the following: 1 enter alphanumeric date; 2 enter commands to the display screen. To enter alphanumeric date, an alphanumeric keyboard is provided.A conventional typewriter-like keyboard allows the designer to input numerical and alphabetic characters into the system. The alphanumeric keyboard can also be used to enter commands and instructions to the system. However, other input devices accomplish this function more conveniently. Special function keyboards have been developed to allow entry of a command in only one or tow keystrokes. These special keypads have from 10 to 50 function keys, depending on the system. However, each key provides more than one function, depending on the commands to a CAD system is the electronic tablet, an electronically sensitive board on which an instruction set is displayed, and commands are entered using a puck orelectronic pen.Cursor control permits the operator to position the cursor in the screen to identify a location where some function is to be executed. For example, to draw a straight line on the screen, the endpoints of the line can be identified by locating the cursor in sequence at the tow points and giving the command to construct the line. There are various cursor control devices used in CAD, including pucks, mousse, joysticks, trackballs, thumbwheels, light pens, and electronic tablets. An input device for entering coordinates from an existing drawing into the CAD system is a digitizer, which consists of a large flat board and an electronic tracking element such as a puck that can be moved across the surface of the board to record x-and y-coordinate positions.1.2Digital Computer CAD applications require a digital computer with a high-speed central processing unit; math coprocessor systems have 32-bit processors, which permit high-speed execution of CAD graphics and engineering analysis applications.Several CAD system configurations are available within the general arrangement show in Fig.18.5. Let us identify three principal configurations, illustrated in Fig.18.6: a host and terminal, b engineering workstation, and c CAD system based on a personal computer.The host and terminal was the original CAD configuration in the 1970s and early 1980 when the technology was first developing, for manyyears, it was the only configuration available. In this arrangement, a large mainframe computer or a minicomputer serves as the host for one or more graphics terminals. These systems were expensive, each installation typically representing an investment of a million dollars or more. The powerful microprocessors and high-density memory devices that are so common today were not available at that time. The only way to meet the computational requirements for graphics processing and related CAD applications was to use a mainframe connected to multiple terminals operating on a time-sharing basis. Host and terminal CAD systems are still used today in the automotive industry and other industries sin which it is deemed necessary to operate a large central databaseAn engineering workstation is a stand-alone computer system that is dedicated to one user and capable of executing graphics software and other programs requiring high-speed computational power. The graphics display is a high-resolution monitor with a large screen. As shown in our figure, engineering workstations are often networked to permit exchange of date files and programs between users and to share plotters and date storage devices.A PC-based CAD system is a PC with high-performance CPU and medium-to-high resolution graphics display screen. The computer is equipped with a large random access memory, math coprocessor, and large-capacity hard disk for storage of the large applications softwarepackages used for CAD. PC-based CAD systems can be networked to share files, output devices, and for other purposes. Starting around 1996, CAD software developers began offering products that utilize the excellent graphics environment of Microsoft Windows NT, thus enhancing the popularity and familiarity of PA-based CAD.When the engineering workstation is with the PC-based system, the former is superior in terms of most performance criteria. Its capacity to efficiently accomplish 3-D geometric modeling and execute other advanced software exceeds that of a PC, and this makes the workstation more responsive and interactive than a PC-based CAD system. However, the performance characteristics of PCs are improving each year, and the prices of engineering workstations are dropping each year, so that the distinction between the two types is becoming blurred.1.3Plotters and Printers The CRT display is often the only output device physically located at the CAD workstation. There is a need to document the design on paper. The peripherals of the CAD system include one more or more output devices for this purpose. Among these output devices are the following.Pen plotters. There are x-y plotters types used to produce high accuracy line drawings Electrostatic plotters. These are faster devices based on the same technology as photocopying. The resolution of drawings from electrostatic plotters is generally lower than those made by a penplotter.Dot-matrix printers. In the operation of these printers, small hammers strikes an ink ribbon against the paper to form a drawing consisting of many ink dots. Ink jet printers. These are similar to dot-matrix printers except that the dots are formed by high-speed jets of ink impacting the paper.Storage Devices. Storage peripherals are used in CAD system to store programs and data files. The storage medium is usually a magnetic disk or magnetic tape. Files can be retrieved more quickly form magnetic disks, which facilitates loading and exchange of files between CPU and disk. Magnetic tape is less expensive, but more time is required to access a given file due to the sequential file storage on the tape. It is suited to disk backup, archival files, and transfer to output devices.CAM, CAD/CAM, AND CIMWe have briefly defined the terms CAM/CAM, and CIM in our introduction. Let us explain and differentiate these terms more thoroughly here. The term computer integrated manufacturing is sometimes used interchangeably with CAM and CAD/CAM. Although he terms closely related, our assertion is that CIM possesses a broader meaning than does either CAM or CAN/CAM.2 Computer-Aided ManufacturingComputer-aided Manufacturing is defined as the effective use of computer technology in manufacturing planning and control. CAD is most closely associated with functions in manufacturing engineering, such as process planning and numerical control part programming. With reference to our model of production, the application of CAM can be divided into two broad categories: 1 manufacturing planning and 2 manufacturing control. Let us provide a brief discussion of them here to complete our definition of CAM.2.1 Manufacturing Planning CAM applications for manufacturing planning are those in which the computer is used indirectly to support the production function, but there is no direct connection between the computer and the process. The computers used “off-line” to provide information for the effective planning and management of production activities. The following list surveys the important applications of CAM in this category:Computer-aided process planning. Process planning is concerned with the preparation of routes sheets that list the sequence of operations and work centers required to produce the product and its computers. CAPPsystems are available today to prepare these route sheets.Computer-assisted NC part programming. The subject of part programming for NC was discussed. For complex part geometries, computer-assisted part programming represents a much more efficient method of generating the control instructions for the machine tool that manual part programming is.Computerized mach inability date systems. One of the problems in operating a metal cutting machine tool is determining the speeds and feeds that should be used to machine a given work part, computer programs have been written are based on date that have been obtained either in the factory or laboratory that relate tool life to cutting conditions.Development of work standards. The time study department has the responsibility for setting time standards on direct labor jobs performed in the factory. Establishing standards by direct time study can be a tedious and time-consuming task. There are several commercially available computer packages for setting work standards. These computer programs use standards time data that have been developed for basic work elements that comprise any manual task. By summing the times for the individual elements required to perform a new job, the program calculates the standard time for the job.Cost estimating. The task of estimating the cost of a new product has been simplified in most industries by computerizing several of thekey steps required to prepare the estimate. The computer is programmed to apply the appropriate labor and overhead rates to the sequence of planned operations for the components of new products. The program then sums the individual component costs form the engineering bill of materials to determine the overall product cost.2.2Production and inventory planning The computer has found widespread use in many of the functions in production and inventory planning. These functions include: maintenance of inventory records, automatic reordering of stock items when inventory is depleted, production scheduling, maintaining current priorities for the different production orders, material requirements planning, and capacity planning.Computer-aided line balancing. Finding the best allocation of work elements among stations on an assembly line is a large and difficult problem if the line is of significant size. Computer programs have been developed to assist in the solution of this problem.Manufacturing Control. The second category of CAM applications is concerned with developing computer systems to implement the manufacturing control function. Manufacturing control is concerned with managing and controlling the physical operations in the factory. These management and control areas include:2.3Process monitoring and control.Process monitoring and control is concerned with observing and regulating the production equipment and manufacturing processes in the plant. We have previously discussed process control. The applications of computer process control are pervasive today in automated production systems. They include transfer lines, assembly systems, NC, robotics, material handling, and flexible manufacturing systems. All of these topics have been covered in earlier chapters.Quality control includes a variety of approaches to ensure the highest possible quality levels in the manufactured product.Shop floor control. Shop floor control refers to production management techniques for collecting data from factory operations and using the data to help control production and inventory in the factory.Inventory control is concerned with maintaining the most appropriate levels of inventory in the face of two opposing objectives: minimizing the investment and storage costs of holding inventory and imizing service to customers.The term just-in-time refers to a production system that is organized to deliver exactly the right number of each component to downstream workstations in the manufacturing sequence just at the when that component is needed. The term applies not only to production operations but to supplier delivery operations as well.CAD/CAM is concerned with the engineering function in both design and manufacturing. Product design, engineering analysis, and documentation of the design represent engineering activities in design. Process planning, NC part programming, and other activities associated with CAM represent engineering activities in manufacturing. The CAD/CAM systems developed during the 1970s and early 1980s were designed primarily to address these types of engineering problems. In addition, CAM has evolved to include many other functions in manufacturing, such as material requirements planning, production scheduling, computer production monitoring, and computer process control.It should also be noted that CAD/CAM denotes an integration of design and manufacturing activities by means of computer systems. The method of manufacturing a product is a direct function of its design. With conventional procedures practiced for so many years in industry, engineering drawings were prepared by design draftsmen and later used by manufacturing engineers to develop the process plan. The activities involved in designing the product were separated from the activities associated with process planning. Essentially a two-step procedure was employed. This was time-consuming and involved duplication of effort by design and manufacturing personnel. Using CAD/CAM technology, it is possible to establish a direct link between product design and manufacturing engineering. In effect, CAD/CAM is one of the enablingtechnologies for concurrent engineering. It is the goal of CAD/CAM not only to automate certain phases of design and certain phases of manufacturing, but also to automate the transition form design to manufacturing. In the ideal CAD/CAM system, it is possible to take the design specification of the product, this conversion being done automatically controlled machine tool. As part of the process plan, the NC part program is generated automatically by CAD/CAM. The CAD/CAM system downloads the NC program directly to the machine tool by means of a telecommunications network. Hence, under this arrangement, product design, NC programming, and physical product。

快速成型制造技术

快速成型制造技术
第八章 快速成型制造技术
Rapid Prototyping Manufacturing Technique
一、快速原型技术简介
快速成型(Rapid Prototyping) 是由三维 CAD模型直接驱动的快速制造任意复杂形状 三维实体的总称。 它集成了CAD技术、数控技术、激光技 术和材料技术等现代科技成果,是先进制造 技术的重要组成部分。
立体光固化成型法原理图
二、RP 工艺方法简介
1.光固化法
Stereo Lithography Apparatus——SLA
SLA工艺的优点是精度较高,一 般尺寸精度可控制在0.01mm;表面质 量好;原材料利用率接近100%;能制造 形状特别复杂、精细的零件;设备市场 占有率很高。缺点是需要设计支撑;可 以选择的材料种类有限;制件容易发生 翘曲变形;材料价格较昂贵。 该工艺适合比较复杂的中小型零 件的制作。
(1)成型材料种类多, (1)成型速度快; 成型件强度高; (2)成型设备便宜。 (2)精度高,表面质 量好,易于装 配; (3)无公害,可在办 公室环境下进 行。
缺点
(1)需要支撑结构; (2)成型过程发生物 理和化学变化 ,容易翘曲变 形; (3)原材料有污染; (4)需要固化处理, 且不便进行。
紫外光快速成型机的工作原理
三、SCPS350紫外光快速成型机及制作过程 (1)基本原理
光敏树脂快速成型中激光束按照 数控指令扫描,工作平台容器内液态 光敏树脂逐层固化并粘结在一起。从 最底层开始,逐层固化,生成三维原 形实体。工作台每次下降高度即为分 层厚度,分层越薄,加工出的零件的 精度越高。
激光头 热压辊 涂覆纸
工件
4.分层实体制造
Laminated Object Manufacturing——LOM

快速成型

快速成型

CNC(Computerized Numerical Control),是带有刀库和自动换刀装置的一种高度自动化的多功能数控机床。

CNC加工是通过对三维数据进行编程、拆分,直接加工出所需的产品,加工精度高,加工出的零件可进行喷涂、电镀、丝印、包覆等表面处理,可进行装配、更好的体现产品的设计功能。

可加工材料:塑料:ABS、PC、PP、PE、POM、PA、PMMA、EPS…金属:钢材、铝合金、锌合金、铜…SLA(StereoLithography Apparatus)光固化原型制造工艺,也常被称为立体光刻成型,该工艺自1988年问世以来,已成为目前世界上研究最深入、技术最成熟、应用最广泛的一种快速成型工艺方法。

它以光敏树脂为原料,通过计算机控制紫外激光聚集到液态光固化材料(如光固化树脂)表面,由点到线到面,完成一个层面的建造,令其有规律地固化,激光使其逐层凝固成型。

而后升降移动一个层片厚度的距离,重新覆盖一层液态材料,再建造一个层面,由此层层迭加成为一个三维实体。

这种方法能简捷、全自动地制造出表面质量和尺寸精度较高、几何形状较复杂的原型。

优点:这种方法适合成形小件,表面质量好、原材料利用率将近100%,能制造形状特别复杂(如空心零件)、特别精细(如首饰等)的零件,并且由于紫外激光波长短,可以得到很小的聚焦光斑,从而得到较高的尺寸精度。

缺点:(1) 需要设计支撑结构,才能确保在成形过程中制件的每一个结构部分都能可靠定位;(2) 成形中有物象变化,翘曲变形较大,通过支撑结构加以改善;(3) 液态树脂固化后的性能与常用的工程塑料尚有差距,一般较脆,易断裂,难以进行受力和耐热等功能实验。

SLA工作原理设备SLS (Selective Laser Sintering )俗称粉末烧结,采用CO2激光器为能量源,通过红外激光束使塑料、蜡、陶瓷和金属(或复合物)的粉末材料均匀地铺在加工平面上。

激光束在计算机的控制下通过扫描器以一定的速度和能量密度扫描。

快速成型专业技术及原理

快速成型专业技术及原理

RP技术简介快速原型制造技术,又叫快速成形技术,(简称RP技术);英文:RAPID PROTOTYPING(简称RP技术),或RAPID PROTOTYPING MANUFACTUREING,简称RPM。

快速成型(RP)技术是九十年代发展起来的一项先进制造技术,是为制造业企业新产品开发服务的一项关键共性技术, 对促进企业产品创新、缩短新产品开发周期、提高产品竞争力有积极的推动作用。

自该技术问世以来,已经在发达国家的制造业中得到了广泛应用,并由此产生一个新兴的技术领域。

RP技术是在现代CAD/CAM技术、激光技术、计算机数控技术、精密伺服驱动技术以及新材料技术的基础上集成发展起来的。

不同种类的快速成型系统因所用成形材料不同,成形原理和系统特点也各有不同。

但是,其基本原理都是一样的,那就是"分层制造,逐层叠加",类似于数学上的积分过程。

形象地讲,快速成形系统就像是一台"立体打印机"。

RP技术是在现代CAD/CAM技术、激光技术、计算机数控技术、精密伺服驱动技术以及新材料技术的基础上集成发展起来的。

RP技术的基本原理是:将计算机内的三维数据模型进行分层切片得到各层截面的轮廓数据,计算机据此信息控制激光器(或喷嘴)有选择性地烧结一层接一层的粉末材料(或固化一层又一层的液态光敏树脂,或切割一层又一层的片状材料,或喷射一层又一层的热熔材料或粘合剂)形成一系列具有一个微小厚度的的片状实体,再采用熔结、聚合、粘结等手段使其逐层堆积成一体,便可以制造出所设计的新产品样件、模型或模具。

快速成型机的工艺立体光刻成型sla层合实体制造lom熔融沉积快速成型fdm激光选区烧结法SLS多相喷射固化mjs多孔喷射成型mjm直接壳法产品铸造dspc激光工程净成型lens选域黏着及热压成型SAHP层铣工艺lmp分层实体制造som自美国3D公司1988年推出第一台商品SLA快速成形机以来,已经有十几种不同的成形系统,其中比较成熟的有SLA、SLS、LOM和FDM等方法。

快速成型技术的原理

快速成型技术的原理

快速成型技术的原理、工艺过程及技术特点:1 快速成型介绍RP技术简介快速原型制造技术,又叫快速成形技术,(简称RP技术);英文:RAPID PROTOTYPI(NG简称RP技术),或RAPID PROTOTYPING MANUFACTUR,E简IN称G RPM。

快速成型(RP)技术是九十年代发展起来的一项先进制造技术,是为制造业企业新产品开发服务的一项关键共性技术, 对促进企业产品创新、缩短新产品开发周期、提高产品竞争力有积极的推动作用。

自该技术问世以来,已经在发达国家的制造业中得到了广泛应用,并由此产生一个新兴的技术领域。

RP技术是在现代CAD/CAM技术、激光技术、计算机数控技术、精密伺服驱动技术以及新材料技术的基础上集成发展起来的。

不同种类的快速成型系统因所用成形材料不同,成形原理和系统特点也各有不同。

但是,其基本原理都是一样的,那就是" 分层制造,逐层叠加" ,类似于数学上的积分过程。

形象地讲,快速成形系统就像是一台" 立体打印机" 。

RP 技术的优越性显而易见:它可以在无需准备任何模具、刀具和工装卡具的情况下,直接接受产品设计(CAD)数据,快速制造出新产品的样件、模具或模型。

因此,RP 技术的推广应用可以大大缩短新产品开发周期、降低开发成本、提高开发质量。

由传统的"去除法"到今天的"增长法" ,由有模制造到无模制造,这就是RP技术对制造业产生的革命性意义。

2、它具体是如何成形出来的呢?形象地比喻:快速成形系统相当于一台"立体打印机"。

快速成型属于离散/堆积成型。

它从成型原理上提出一个全新的思维模式维模型,即将计算机上制作的零件三维模型,进行网格化处理并存储,对其进行分层处理,得到各层截面的二维轮廓信息,按照这些轮廓信息自动生成加工路径,由成型头在控制系统的控制下,选择性地固化或切割一层层的成型材料,形成各个截面轮廓薄片,并逐步顺序叠加成三维坯件.然后进行坯件的后处理,形成零件。

快速成型技术

快速成型技术

快速成型技术快速成型技术简介快速成型技术(Rapid Prototyping Technology-RPT)属于先进制造技术范畴机械工程学科非传统加工工艺(或称为特种加工)是将CAD、CAM、、激光、精密伺服驱动和新材料等先进技术集成的一种全新制造技术。

它通过叠加成型方法可以自动而迅速地将设计的三维CAD模型转化为具有一定结构和功能的原型或直接制造零件。

与传统的制造方法相比,它具有生产周期短,成本低的优势,并且可以灵活地改变设计方案,实现柔性生产,在新产品的开发中具有广阔的应用前景。

目前世界上投入应用的快速成形的方法有十多种,主要包括立体印刷(SLA-StereoLithgraphy Apparatus)、分层实体制造(LOM-Laminated obxxxxject Manufacturing)、选择性激光烧结(SLS—Selective Laser Sintering)、熔化沉积制造(FDM-Fused Deposition Modeling)、固基光敏液相(SGC-Solid Ground Curing)等方法。

其中选择性激光烧结(SLS)技术具有成型材料选择范围宽、应用领域广的突出优点,得到了迅速发展,正受到越来越多的重视。

SLS方法具有以下的优点:由于粉末具有自支撑作用,不需另外支撑;材料广泛,不仅包括各种塑料材料、蜡和覆膜砂,还可以直接生产金属和陶瓷零件。

且材料可重复使用,利用率高。

快速成型技术工作原理使用CO2 激光器烧结粉末材料(如蜡粉、PS粉、ABS粉、尼龙粉、覆膜陶瓷和金属粉等)。

成型时先在工作台上铺上一层粉末材料激光束在计算机的控制下按照截面轮廓的信息对制件实心部分所在的粉末进行烧结。

一层完成后工作台下降一个层厚再进行下一层的铺粉烧结。

如此循环,最终形成三维产品。

快速成型技术应用选择性激光烧结快速成型(Selective Laser Sintering Rapid Prototyping) 技术(简称SLS技术)由于具有成型材料选择范围宽、应用领域广的突出优点,得到了迅速的发展,正受到越来越多的重视。

第三章 快速成型技术(中英文)

第三章 快速成型技术(中英文)
▪ Discrete accumulation manufacturing is put forward on the basis of summarizing the development of Rapid Prototyping in the modern forming theory, Indicating the discreteness in the Model information processing. It emphasizes material accumulation in the physical process and embodies the basic prototyping principle. It also possess strong generality and adaptability.
成形机制造一系列 层片并自动将它们 联接起来,得到三 清理零件表面, 维物理实体 去除辅助支撑 结构
major character of Rapid Prototyping technology
➢ The highly flexibility is the main difference between it and NC machine. No matter the numerical control machine or the machining center, they are designed according to a certain type parts. For example, turning center and milling machining center, etc. For different parts need to be different clamping, using different tools. Although their flexibility is very high and produce a batch of parts which contains only a few tens of parts, or even a few parts, however it doesn't increase additional cost. But they cannot be used alone, the material needed to be made into blanks firstly. However RP technology has the highest flexibility. For any parts which their dimensions are not more than forming range. Without any special tools, its model can be manufactured quickly and easily. From the view of manufacturing model, RP has the incomparable advantages of NC machine tools. That is highly flexible, convenient and fast.

快速成型制造技术

快速成型制造技术

快速成型制造技术特种加工技术是先进制造技术的重要组成部分,是衡量一个国家制造技术水平和能力的重要标志,在我国的许多关键制造业中发挥着不可替代的作用。

采用特种加工技术可以加工特殊材料,且加工中无切削力,能够进行微细加工及复杂的空间曲面成形,所以能够解决航空航天、军工、汽车、模具、冶金、机械等工业中的关键技术难题,从而逐步形成新兴的特种加工行业。

特种加工技术主要包括电加工技术、高能束流加工技术、快速成型制造技术等,其中以快速成型制造技术对现代制造业的影响最为重大。

快速成型制造技术(Rapid Prototyping Manufac?turing,RPM),就是根据零件的三维模型数据,迅速而精确地制造出该零件。

它是在20世纪80年代后期发展起来的,被认为是最近20年来制造领域的一次重大突破,是目前先进制造领域研究的热点之一。

快速成型制造技术是集CAD技术、数控技术、激光加工、新材料科学、机械电子工程等多学科、多技术为一体的新技术。

传统的零件制造过程往往需要车、钳、铣、磨等多种机加工设备和各种夹具、刀具、模具,制造成本高,周期长,对于一个比较复杂的零件,其加工周期甚至以月计,很难适应低成本、高效率的加工要求。

快速成型制造技术能够适应这种要求,是现代制造技术的一次重大变革。

快速成型产品随着CAD建模和光、机、电一体化技术的发展,快速成型技术的工艺方法发展很快。

目前已有光固法(SLA)、层叠法(LOM)、激光选区烧结法(SLS)、熔融沉积法(FDM)、掩模固化法(SGC)、三维印刷法(TDP)、喷粒法(BPM)等10余种。

1、光固化立体造型(Stereolithography,SLA)该技术以光敏树脂为原料,将计算机控制下的紫外激光,以预定零件各分层截面的轮廓为轨迹,对液态树脂逐点扫描,由点到线到面,使被扫描区的树脂薄层产生聚合反应,从而形成零件的一个薄层截面。

当一层固化完毕,升降工作台移动一个层片厚度的距离,在原先固化好的树脂表面再覆盖一层新的液态脂以便进行新一层扫描固化。

快速成型技术的原理

快速成型技术的原理

快速成型技术的原理、工艺过程及技术特点:1 快速成型介绍RP技术简介快速原型制造技术,又叫快速成形技术,(简称RP技术);英文:RAPID PROTOTYPIIN简称RP技术),或RAPID PROTOTYPING MANUFACTURE简G RPMI快速成型(RP技术是九十年代发展起来的一项先进制造技术,是为制造业企业新产品开发服务的一项关键共性技术, 对促进企业产品创新、缩短新产品开发周期、提高产品竞争力有积极的推动作用。

自该技术问世以来,已经在发达国家的制造业中得到了广泛应用,并由此产生一个新兴的技术领域。

RP技术是在现代CAD/CAM技术、激光技术、计算机数控技术、精密伺服驱动技术以及新材料技术的基础上集成发展起来的。

不同种类的快速成型系统因所用成形材料不同,成形原理和系统特点也各有不同。

但是,其基本原理都是一样的,那就是"分层制造,逐层叠加",类似于数学上的积分过程。

形象地讲,快速成形系统就像是一台"立体打印机" IRP 技术的优越性显而易见:它可以在无需准备任何模具、刀具和工装卡具的情况下,直接接受产品设计(CAD数据,快速制造出新产品的样件、模具或模型。

因此,RP技术的推广应用可以大大缩短新产品开发周期、降低开发成本、提高开发质量。

由传统的"去除法"到今天的"增长法",由有模制造到无模制造,这就是RP技术对制造业产生的革命性意义。

2、它具体是如何成形出来的呢?形象地比喻:快速成形系统相当于一台"立体打印机"。

快速成型属于离散/堆积成型。

它从成型原理上提出一个全新的思维模式维模型,即将计算机上制作的零件三维模型,进行网格化处理并存储,对其进行分层处理,得到各层截面的二维轮廓信息,按照这些轮廓信息自动生成加工路径,由成型头在控制系统的控制下,选择性地固化或切割一层层的成型材料,形成各个截面轮廓薄片,并逐步顺序叠加成三维坯件.然后进行坯件的后处理,形成零件。

快速成型技术

快速成型技术

快速成形技术快速成形技术又称快速原型制造(Rapid Prototyping Manufacturing,简称RPM)技术,诞生于20世纪80年代,这种技术是基于为了满足日益变化的用户需求,又要求制造技术有较强的灵活性,能够以小批量甚至单件生产而不增加产品的成本的背景下应运而生的。

这种技术首先产生于美国,并且很快扩展到欧洲和日本。

快速成形技术是在计算机控制下基于离散、堆积的原理采用不同方法堆积材料,最终完成零件的成形与制造的技术。

从成形角度看,零件可视为“点”或“面”的叠加。

从CAD电子模型中离散得到“点”或“面”的几何信息,再与成形工艺参数信息结合,控制材料有规律、精确的由点到面,由面到体的堆积零件。

从制造角度看,它根据CAD造型生成零件三维几何信息,控制多维系统,通过激光束或其他方法将材料逐层堆积而形成原型或零件。

快速成形的工艺方法目前已有几十种之多,但其中主要工艺有四种基本类型:光固化成型法(SLA)、分层实体制造法(LOM)、选择性激光烧结法(SLS)和熔融沉积制造法(FDM)。

快速成形技术优点很多,主要特征是由CAD模型直接驱动快速制造任意复杂形状三维实体,它不受复杂形状的任何限制,可迅速地将示于计算机屏幕上的设计变为可进一步评估的实物,大大提高了设计生产周期。

经过近30多年的发展,此技术已可实际应用。

但此技术仍是一项尖端技术,目前在国外应用还较广,但还没完全普及,市场上也只有为数不多的几家公司生产所需设备。

这项技术对材料环境要求也较高,所能成形的模具也是小型模具,因此这项技术还有很大的发展前景。

我认为这项技术在未来相当长的一段时间里会有很大的发展,其会向大型制造与微型制造进军,材料适用范围会更广,制造精度会更高,所需设备也会更加智能化,不需要专门操作人员,并且向概念模型、生产和专用成形三个方向分化。

快速成型技术Rapid Prototyping

快速成型技术Rapid Prototyping

RT方法的分类: 按功能用途可分为:塑料模、铸(型)模、冲压模、锻 造模及石墨电极研磨母模。 按制模材料可分为简易模(也称作软模、经济模或非 钢制模)和钢制硬模。 根据不同的制模工艺方法,快速模具可分直接快速模 具和间接快速模具。 直接快速模具,亦即快速成型模具,以快速成型件直 接作为成形模具。间接快速模具,亦即型腔复制模具,以 快速成型件为母模,通过型腔复制制作模具,包括硅橡胶 复制、金属冷喷涂、精密铸造、树脂材料型腔复制等。
LOM原理图
工作台上升
多余网格部分的去除
头盖骨
薄壳件
LOM 2030 H机器外观
LOM优点: (1)成型效率高,LOM工艺只需在片材上切割出零件截 面的轮廓,而不用扫描整个截面,因此成型厚壁零件的速 度较快,易于制造大型零件; (2)无翘曲变形,工艺过程中不存在材料相变,因此没有 热应力、膨胀和收缩不易引起翘曲变形; (3)无需加支撑,工件外框与截面轮廓之间的多余材料在 加工中起到了支撑作用,所以LOM工艺无需加支撑。 LOM缺点:材料浪费严重,表面质量差。
模具:制模、 试模、修模, 时间,成本
设计
试制
试验
征求用户意见
RP:设计、 成型, 时间,成本
市场推销
生产
修改定型
RP Prozesskette(产品开发链)
• 1. 3D-CAD-Volumenmodell • 2. Triangulation: alle Oberflächen durch Dreiecke annähren • 3. Schnittstelle: STL—(Standard Transfer Language)-Format • 4. Slice-Prozess • 5. Bauprozess
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山东英才学院毕业设计(论文)外文资料翻译学院机械制造与自动化学院专业机械设计制造及其自动化学生姓名韩俊龙班级学号2008级本科二班200801010109外文出处附件:1.外文资料翻译译文;2.外文原文指导教师评价:1.翻译内容与课题的结合度:□优□良□中□差2.翻译内容的准确、流畅:□优□良□中□差3.专业词汇翻译的准确性:□优□良□中□差4.翻译字符数是否符合规定要求:□符合□不符合指导教师签名:年月日快速成型制造的介绍快速成型这个术语是对于不通过机器和工具的三维造型生产而产生的一种新的相关的表示.通过快速生产的准确能力,用电脑设计系统帮助切实的造型的设计生产,第一个快速成型的系统于1988年在美国的市场内被引进并且给工程师一个通过CAD 来设计三维实物的机会且成功的生产出复杂表面的模型.使用这项技术的操作优势如下: 固态模型的高速产生.这个模型的复杂性对于生产不能形成任何的限制.最早使用这些模型是用来帮助设计者决定形状和适当性.它也能提供给预期的顾客展示三维实物的销售群,这将远远优于那些很多人发现很难去解释的传统直角作图:1.一小部分传统方法的价值是把准确的物理模型转化成三维影象.2.改进设计的讯息帮助删除设计的错误.3.对于新的产品减短上市的时间.4.自从原形相比做图更能被理解后它就能作为一种强有力的工具.5.这技术的发展到达了入许多传统领域,吸引技巧和知识导致了直接地和间接地使用作为样式和模型的三维对象为软的工具模型。

6.模型的生产是通过用机器制造有一定数量的限制。

7.在成形期间被除去的材料是难回收的。

8.用机器制造以钻井转动的碾碎的火花电蚀等的形式。

由它可能导致的形状限制。

9.在设计变动情形下,常规凿出的装饰例如样式,核心装箱,模子,夹具等。

变得昂贵而难变更,并且在许多情况下,可以要求完全再制造。

快速成型法是不同于以通过增加物质层数的常规制造方法,直到达到所期望的锐利程度,立刻减少或避免材料的损失层数。

RP&M能做什么?为开发的样式、模子和原型去极大地缩短时间。

一些制造业企业开始对于一些复杂部件的制造和成型的成分使用快速成型的方法。

在过去几年,各种各样新的迅速制造业技术,通常称为快速成型和制造(RP&M),已经涌现了;被开发的技术包括立体声石版印刷(SL),所选择的激光焊接(SLS),合并的证言塑造(FDM),薄片叠成物体的制造业(LOM),和3D打印(3D Print)。

他们有一个共同的重要特点; 原型零件是通过增加材料而不是除去材料导致的。

这简化3D部分生产过程到增加过程的第2层数,以便零件可以直接地由它的计算机模型生产。

快速成型的机器是通过切计算机模型来制造处理CAD数据入层数,每层数是典型地0.1-0.25毫米厚的机器然后使用这数据一层一层去修建,每一层都将被拈合成以前的样子直到一个坚实对象被形成。

由于这个建筑被碾压的方法一个有台阶的表面在弯曲的表面上被开发,如果过程的最大好处被了解,那么其中是根本的将被撤除,有台阶建筑的图示,是要求分步处理的.更多的发展由与模型的扩展而引起的问题已经提示了,使用它就像一个一次性部件(象蜡本身在失去蜡过程中),那里的合成树脂模型导致了形成坚实的墙壁,扩展在“燃烧的”阶段期间来减弱陶瓷的外壳,并且在生火和铸件阶段都能导致失败。

3D系统GmbH公司,开发了机器和软件,一起允许模型以蜂窝的形式被修建。

蜂窝结构在本身崩溃在“燃烧的”因而避免扩展的问题。

蜂窝结构的每个口袋通过一个小孔连接到它的旁边从而考虑到未固化的树脂在使用之前被排泄出去。

其它快速成型的工具直接加工的方法-比如金属喷镀-也被开发,并且看上去这在较不复杂零件的生产似乎有潜力,但不可避免的一些细节将丢失。

ARRK有限公司是快速成型的欧洲公司,伦敦,已经开发了薄片技术,这除去了很多在机械加工中固有的不准确性。

他们宣称他们是世界上第一家能够达到0.05毫米厚度的准确制造。

ARRK的开发小组使用了微妙的机械改变的组合到它的四个立体声石版印刷(SL),快速成型的机器安装,并且私有的技术去克服湿度。

它也要求了对于树脂的知识.使用这种新技术,公司现在能生产极端准确优质主要零件和工具。

以0.05mm 层数,所有的修造是精确的,除了消灭台阶跨步的作用。

另外,显著减少对精整的需要。

结果,过程作为理想的开关,电子元件是理想的或其中任一微小的详细的部件。

快速成型和制造的当前应用的区域设计工程(1)形象运用快速成型和制造技术,一个复杂部分的原型在短期可以被制作,因此工程师能非常迅速的评估设计,因为这很难确切的使实际复杂的产品看上去形象化。

(2)证明和优化改进产品质量总是制造业的一个重要问题。

快速成型和制造能够快速的生产不用坚固的工具和人工成本。

结果,产品质量可以改进在有限的时间表之内和以付得起的费用。

(3)叠代运用快速成型和制造技术,在短时间内审阅多样的设计叠代和极大地减少式样研制时间是可能的。

我们可以为有生产力地使用快速成型和制造原型学习。

通过提供一个物理产品在更加初期的设计,我们可以加速处理计划和凿出的装饰设计。

另外,通过准确描述复杂几何,原型在解释方案可能帮助减少问题在车间上。

可能也用于工具的发展为模子和主模浇铸。

要协助产品销售,原型可以用于展示概念,设计想法,是由公司的能力导致它。

物理模型的现实说明设计的可行性。

并且,原型可以用于获取顾客的反馈为设计修改,以便最终的产品将符合顾客的要求。

Rapid Prototyping and manufacturing IntroductionThe term “rapid prototyping” (RP) is a relatively new expression for the generation three-dimensional models manufactured without the need for machining or products designed on a computer aided design system, the first rapid prototyping system was introduced on to the US market in 1988 and gave the engineer the opportunity to produce 3 dimensional objects directly from Computer Aided Design (CAD) date and succeed in the cost-effective production of patterns and moulds with complex surfaces.The principle advantages of using this technology are:High speed at which the solid model is generated.The complexity of the model does not form any limitation to its production.The early use of these models was to assist the designer in determining fitness and form. It also provided the sales team with a 3 dimensional object to show to a prospective customer, this being far better than the traditional orthographic drawing which many people find difficult to nterpret. The benefits of RP: 1.Converts 3D CAD images into accurate physical models at a fraction of the cost of traditional methods.2.Improves design communication and helps eliminate design mistakes.3.Reduces “time to market” for a new product.4.Can be used as a powerful marketing tool since the prototype can be seen rather than the drawing.5..The development of this technology has reached into many of the traditional fields, attracting the interest of artisans whose skill any knowledge has led to 3-D objects being used directly and indirectly as patterns and model for soft tooling.6.Production of models by machining has a number of limitations.7. Material removed during forming is difficult to reclaim.8.Machining in the form of drilling turning milling spark erosion etc., is limited by the shapes it can produce.9.In the event of design change, conventional tooling such as patterns ,core boxes, dies, jigs etc. ,become expensive to alter ,and in many cases, may require complete re-manufacture.What RP&M CAN DO?To substantially shorten the time for developing patterns, moulds, and prototypes,some manufacturing enterprises have started to use rapid prototyping methods for complex patterns making and component prototyping. Over the past few years, a variety of new rapid manufacturing technologies, generally called Rapid Prototyping and Manufacturing(RP&M),have emerged ;the technologies developed include Stereo lithography(SL),selectedlaser sintering(SLS),fused deposition modeling(FDM),laminated object manufacturing(LOM),and three dimensional printing (3D Print).They have a common important feature ;the prototype part is produced by adding materials rather than removing materials. This simplifies the 3D part producing processes to 2D layer adding processes so that a part can be produced directly from its computer model.rapid prototyping differs with conventional manufacturing methods by adding material layer by layer until the desired sharp is achieved, immediately reducing or avoiding the loss of material.THE BASIC PROCESS IN RPRP machines process CAD data by slicing the computer model into layers ,each layer being typically 0.1-0.25mm thick the machine then uses this data to construct the model layer by layer ,each layer being bonded to the previous until a solid object is formed. Due to this laminated method of construction a stepped surface is developed on curved faces, the removal of which is essential if maximum advantage of the process is to be realized. Schematic representation of the stepped construction, which requires post processing, is on the aboveFigure8.1.DEVELOPMENTMore recent developments have been prompted by problems caused by the expansion of the model where it is used as a disposable pattern (like the wax pattern in the lost wax process),Where the resin model is produced to form solid walls, expansion during the “burning-out” stage weakens the ceramic shell, and can cause failure in the firing and/or casting stages.The company, 3D System GmbH, has developed a machine and software, which together allow for the model to be constructed in the form of a honeycomb. The honeycomb structure collapses in on itself during “burning-out” thus avoiding the problems of expansion. Each pocket of the honeycomb structure is connected to its neighbor by a small hole that allows for the uncured resin to be drained prior using. Other methods of producing tooling directly from the rapid prototype-such as metalspraying –are also being developed, and this seems to have potential in the production of less complexparts, although it is inevitable that some detail will be lost.Prototyping Company ARRK EUROPE LTD, London, has developed a thin layer technology, which removes many of the inaccuracies inherent in mechanical finishing. It claims to be the first company in the world to achieve 0.05mm layer build accuracy. ARRK’s development team used a combination of subtle mechanical alterations to setting up of its four stereo lithography (SL) rapid prototyping machines and proprietary techniques to over come de-wetting. It also called upon its knowledge of resins.THE BASIC PROCESS IN RPRP machines process CAD data by slicing the computer model into layers ,each layer being typically 0.1-0.25mm thick the machine then uses this data to construct the model layer by layer ,each layer being bonded to the previous until a solid object is formed. Due to this laminated method of construction a stepped surface is developed on curved faces, the removal of which is essential if maximum advantage of the process is to be realized. Schematic representation of the stepped construction, which requires post processing, is on the aboveFigure8.1.Using this new technology, the company is now able to produce extremely accurate high-quality master parts and tooling. With 0.05mm layer, the build is more precise and all but eliminates the stair-stepping effect. In addition, the need for finishing is dramatically reduced. As a result, the process is ideal for switches, electronic components or any finely details part.Current Application Areas of RP&MDesign Engineering(1) VisualizationWith RP&M, the prototype of a complex part can be built in short time, therefore engineers can evaluate a design very quickly, f or it isn’t difficult to visualize exactly what the actual complex product will look like.(2) Verification and optimizationImproving product quality is always an important issue of manufacturing. An RP&M prototype can be produced quickly without substantial tooling and labor cost. As a result, the product quality can be improved within the limited time frame and with affordable cost.(3) IterationWith RP&M technology, it is possible to go through multiple design iterations within a short time and substantially reduce the model development time.ManufacturingWe can use the RP&M prototype for productively studies. By providing a physical product at an earlier design stage, we can speed up process planning and tooling design. In addition, by accurately describing complex geometry, the prototype can help reduce problems in interpreting the blue prints on the shop floor. It can also be used in tooling development for mould and master pattern for castings.MarketingTo assist product sales, a prototype can be used to demonstrate the concept, design ideas, as well as the company’s ability to produce it. The reality of the physical model illustrates the feasibility of the design. Also, the prototype can be used to gain customs’ feedback for design modification so that the final product will meet customs’ requirement.。

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