先进制造技术课程论文01.docx

快速原型技术概述Overview of rapid prototyping technology摘要Abstract近年来，快速原型技术（RP）发展迅速，并被应用于各个工业领域，展现出了它特有的优势。这项技术能利用一些特种材料（比如光固化树脂、粉纸等），直接将cad的三维模型快速成型为实体零件。本文将主要对这项技术的在制造业中的优势和应用范围进行概述，此外，我也会试着讨论此项技术在未来的发展趋势。In recent years, rapid prototyping (RP) technology is developing rapidly , and is used in various industrial fields, demonstrated its unique advantages. This technology can use some special materials (such as UV cureable resin, powder paper, etc.), directly make the three-dimensional model of the CAD rapidly prototype to be solid parts. This article focuses on an overview of the advantages and range of applications of this technology in manufacturing, furthermore I will try to discuss the trends of this technology in the future.关键词：快速原型，制造业，发展趋势Keywords: rapid prototyping, manufacturing, development trend1. RP原理与特点1. RP principle and characteristics 快速原型制造技术兴起于十几年前，与传统的去除型加工不同，RP是一种基于堆积原理的“生长型”加工，也称为分层叠加成形。在计算机的管理与控制下，先将CAD模型离散成一层层截面轮廓信息，然后在RP成形设备上依次制造出各个片层并逐层粘结成一体，从而堆积出三维实体制件。由此可见，RP可以在零件CAD模型的驱动下，快速制造出任意复杂形状的实体。The rapid prototyping technology grow up in more than a decade ago, different from traditional removal machining, RP is a Growing machining based on the principle of accumulation, also known as laminated object manufacturing. Under the management and control of the computer, firstly the CAD model will be separated to several layers which contain the 3D information, then manufacture each layer on the RP forming equipment, and attach layer by layer into one part, at last we get a three-dimensional solid part by accumulating. Thus it can be seen, the RP technology can rapidly manufactured any solid part with complex shapes driven by CAD models.快速原型技术拥有以下特点:The rapid prototyping technology has the following features:（1）快速性，从CAD 设计到完成原型制作通常只需几个小时到几十个小时，加工周期短;（1）Rapidity, from CAD design to complete prototyping it usually takes only a few hours or dozens of hours, machining cycle times are short;（2）低成本，与产品的复杂程度无关，一般制作费用降低50%，特别适合新产品的开发和单件小批量零件的生产;(2) low-cost, regardless of the complexity of the product, generally a 50% reduction in production costs is possible , particularly suitable for the development of the new products and production of single-piece or small quantities of parts;（3）具有高柔性，采用非接触加工的方式，无需任何工夹具，即可快速成型出具有一定精度和强度并满足一定功能的原型和零件。(3) having a high flexibility, the use of non-contact machining, without any tools, can quickly forming a prototype and parts which have a certain accuracy and strength and meeting certain function;（4）高集成化，RP 技术是集计算机、CAD/CAM、数控、激光、材料和机械等一体化的先进制造技术，整个生产过程实现自动化、数字化。(4) high integration, the rapid prototyping technology is an advanced manufacturing which integrated a set of technologies, such as computer, CAD / CAM, CNC, laser, material and machinery , the entire production process achieves automation and digitization. 在实际加工过程中，快速原型技术的成型工艺方法有几十种之多，常见的有SLA（Stereolithgraphy Apparatus），LOM（Laminated Object Manufacturing），SLS（Selective Laser Sintering），FDM（Fused Deposition Modeling）和基于喷射的RP技术。In the actual machining process, the moulding process method of the rapid prototyping technology has a dozens of kinds, the common ones are as follow:SLA（Stereolithgraphy Apparatus），LOM（Laminated Object Manufacturing），SLS（Selective Laser Sintering），FDM（Fused Deposition Modeling）SLAStereolithgraphy ApparatusFDMFused Deposition ModelingSLSSelective Laser SinteringLOMLaminated Object ManufacturingAdvantage (1) high forming speed and forming precision, high surface quality;(2) suitable for small pieces and meticulous pieces. (1) suitable for forming many types of materials, high sample strength, be able to directly manufacture part made of ABS plastic;(2) high dimensional accuracy and good surface quality, easy to assemble;(3) high material utilization;(4) operating environment is clean, safe ,so suitable for office environment. (1) contain the concept of directly metal making, be able to obtain plastic, wax or the metal part directly;(2) high material utilization; shape faster. (1) a high forming precision;(2) only need to cut the contour line, high production efficiency, suitable for bigger pieces and solid parts;(3) the sample made out have the hardness similar to the wooden products, suitable for machinability to a certain degree disadvantage (1)Do further curing treatment after forming;(2) after curing the UV cureable resin will be more brittle, easily broken, low workability;(3) Operating temperature can not exceed 100 , the forming parts are easy to absorb water and swell, and corrosion resistance is weak. (1) a longer forming time;(2) less precise than the SLA when make small pieces and meticulous pieces(1) the forming part always has poor strength and surface quality, also the accuracy is low.(2) in the post-treatment its difficult to ensure the accuracy of the workpiece size, complicated post-treatment process, big sample deformation, difficult to be assembled.(1) is unfit for thin-walled prototype;(2) surface is relatively rough, a stepped pattern in the workpiece surface, polishing after forming is required;(3) easy to absorb water and swell, after forming moisture-proof is required;(4) the workpiece has poor strength, and always lack flexibility. and other rapid prototyping technology.2. RP在制造业中的优势和应用范围the advantages and range of applications of RP 由于快速原型技术自身的特点，在加工过程中，它不需要传统的多坐标数控机床、刀具和夹具，一般只需传统加工方法半数不到的工时和非常小的成本，就能把体现设计思想的CAD模型转化为物理实体，从而可以有效地缩短开发周期，提高企业的竞争力。Due to the characteristics of the rapid prototyping technology, in the machining process, it does not require the traditional multi-coordinate CNC machine tools, cutting tools and fixtures, generally only take less than half of the working hours which the traditional processing methods take and take very little cost as well, and will be able to make the CAD model reflecting the design thinking into a physical solid part, which can effectively shorten the development cycle of the product, improve the competitiveness of enterprises. 首先，快速原型技术在概念设计方面具有天生的优势。概念设汁是产品设计中最关键、最复杂、最具决定性和和创造性的阶段，其重要性体现在两个方面：首先概念设计阶段在很大程度上决定着最终产品的性能、创造性、价格、市场响应速度和效率等，此外，虽然概念设计阶段实际投入的费用只占产品开发总成本的很小一部分，却决定了产品总成本的绝大部分。而且详细设计阶段很难甚至不能纠正概念设计阶段的设计缺陷和错误，它严重影响到产品设计与开发。结合RP技术的优势之后，很显然，概念设计将变的非常顺利，企业可以对市场的变化作出非常快的反应，设计出市场上畅销的产品，并更快纠正概念设计上的缺陷和不足，从而更快的投入生产。Firstly, the rapid prototyping technology has an innate advantage in conceptual design. The conceptual design is the most critical and most complex, the most decisive and creative stage in a product design process, and its importance is reflected in two aspects: Firstly, the conceptual design stage largely determines the performance , creativity, the price of the final product, market response speed and efficiency, etc. In addition, the actual investment costs of conceptual design stage make up only a small fraction of the total cost of product development, while it has decided most of the total cost of the product. And the detailed design stage it is difficult even can not to correct design flaws and errors of the conceptual design stage, it has a serious impact on product design and development. With the advantages of RP technology, it is clear that the concept design will become very smooth, companies can make a very fast response to changes in the market, designs best-selling products on the market, and faster to correct defects and deficiencies in the conceptual design, and be able to make faster production as well. 其次，RP技术并没有仅仅停留在制作概念原型上，经过十几年的发展，国外相继推出了一些直接成形金属材料的RP系统，并开始实际用于快速制作金属模具乃至金属零件。与此同时，RP技术也已能快速制作在实际产品中使用的功能性塑料（比如聚碳酸脂）零件。由此可见，RP技术已经具有了制造最终产品的功能，从而表明它的内涵正从快速原型制造向快速制造（RM，Rapid Manufacturing）方向发展。其中，制作金属模具的发展尤为迅速，以母模为基础来制造各种模具，速度快、成本低，但母模，特别是形状复杂的母模获取不易，而RP技术很容易将体现设计构思的CAD模型变为非金属材料的母模，为快速制模（RT，Rapid Tooling）技术注入了新的活力。Secondly, the rapid prototyping technology is not merely on manufacturing the concept of the production, after ten years of development, the foreign research institute successively launched RP system which can directly shaped metal material, and start to actually use the system for the rapid production of metal moulds and even metal parts. At the same time, RP technology has been able to quickly manufacture functional plastic parts used in the actual product (such as polycarbonate). Thus it can be seen, RP technology has already had the ability to manufacture the final product, thereby it is demonstrating that the connotation of RP is developing from the rapid prototyping to rapid manufacturing (RM, Rapid Manufacturing). Among the several technologies the production of metal moulds is particularly rapid developing, manufacturing all kinds of mould based on a, will be faster, lower-cost, but the, especially master pattern with the complex shape is not easy to obtain, but the RP technology can easily make the CAD model embodying design ideas become the non-metallic materials master pattern, which has injected new vitality for rapidly mould making technology (known as RT, Rapid Tooling).此外，RP技术在医用假肢制造方面有很好的发展前景。医用假肢的外形依病人的不同而不同。我们很容易通过医学影像技术得到假肢三维形状，但用传统方法加工却很难达到精度，而且加工周期长，成本高。利用RP技术则完全不同，它能实现高柔性加工，快速制造出适合人体应用的医用假肢。In addition, the RP technology in the field of manufacturing of medical prostheses has good development prospects. The appearance of medical differs from patient to patient. We can easily obtain the three-dimensional shape of prostheses through medical imaging technology, but it is difficult to achieve machining accuracy using the traditional method, and machining cycle is relatively long, the cost is also so high. The RP technology is completely different, it can achieve a highly flexible manufacturing, and rapidly manufacture the medical prostheses for human application.3. RP在未来的发展趋势3. Development trend of RP in the future 尽管RP技术在制造业领域已经有了如此多的应用，而且与传统加工方式相比拥有如此多的优势，但是，RP技术目前的发展水平也还存在一些局限性。比如： Although RP technology already has so many applications in the manufacturing sector, and compared with the traditional processing methods it has so many advantages, but there are still some limitations on the current level of development of RP technology. For example:（1）成形精度不高。影响RP成形精度的因素很多，它既包括分割处理中存在的误差，也包括成形过程中，由于材料的相变和温度变化而出现的加工误差。此外，成形速度与成形精度之间还存在矛盾，为提高成型精度而减少切片层厚度会降低成形效率，反之，为加快成型速度而增加切片层厚度会降低成型精度。由于精度不够，目前RP技术尚难于制造精度较高的最终产品。(1) Forming accuracy is not high. The factor which influence RP forming precision is various, including not only the errors exist in division processing, but also the errors caused by the phase change and the temperature change of the material in the forming process. In addition, there exists a contradiction between the forming speed and the forming accuracy .Reducing the thickness of the slice layer to improve the forming accuracy will reduce the forming efficiency Conversely, to accelerate the speed, increasing the thickness of the slice layer will reduce the forming accuracy. Due to lack of precision, the RP technique is hard to be used in the manufacturing processing of the final product, which requires high precision.（2）处理工艺成熟的材料范围有限。前文已经提到，目前比较成熟的RP工艺所处理的材料大概只限于树脂、蜡、某些工程塑料和纸等几种。用这些材料制成的零件，即使经过后处理也大多不能作为真正的机械零件使用。而以金属材料作为RP的处理对象的工艺尚不十分成熟，如何提高金属直接成型的加工精度、表面质量和机械性能并降低成本，尚有许多工作要做。(2)The range of materials which can be maturely manufactured by RP technology is limited. As already mentioned before, the materials handled by the more mature RP process is probably only limited to several materials like the resin, wax, some engineering plastics and paper. Parts made of these materials, even after treatment mostly can not be used as a real mechanical part. Processing or technology which take metallic materials as RP object is not mature yet. How to improve the machining accuracy, surface quality and mechanical performance of metal directly forming technology, and how to get lower costs, still needs a lot of work to do. （3）设备投资大、材料费用高。RP工艺的研发成本高，这种研发成本必定转移到相应的工艺装备上去，加之RP设备属小批生产，因而其价格居高不下。此外，RP工艺对材料有特殊要求，其专用成形材料价格相对偏高。设备和材料的价格也影响了RP技术的普及和应用。(3) a large investment in equi