【作者】 邹国林；

【导师】 郭东明； 贾振元；

【作者基本信息】 大连理工大学 ， 机械制造及其自动化， 2002， 博士

【摘要】 现代社会市场竞争日趋激烈，新产品的“上市时间”已成为取胜的关键，因此，要求设计者及制造者尽量缩短产品的开发、制造周期，以适应批量小、品种多、改型快的现代制造模式。快速成型技术(RPM)与快速模具制造技术(RT)能分别用来快速制造具有复杂形状的原型及具有高尺寸精度和低表面粗糙度的各类工模具，因而利用这两种技术能实现快速产品开发的目的。 熔融沉积制造技术(FDM)在零件原型快速制造上已获得成功的应用。基于FDM快速制造模具——生成注塑模或EDM电极时，原型的尺寸、几何精度和表面粗糙度对于最终产品的质量起着决定性的作用，因而必须研究FDM工艺的精度。 本论文首先从粘性和弹性两个方面阐述和研究了熔融态ABS熔体从喷头挤出过程中的流变性能，流变性能的分析和研究不仅有助于更好地理解FDM工艺的挤出丝过程，而且为建立理想轮廓线的补偿模型提供了理论依据。 在对FDM工艺精度进行系统分析的基础上，提出了精度研究的具体内容，即成型过程中的材料收缩及其补偿、由喷头导致的理想轮廓线的补偿和FDM工艺参数的优化。 首先通过理论和实验研究了成型过程中ABS树脂材料收缩对零件尺寸精度的影响，以及收缩的控制与补偿方法。 根据ABS丝从喷头挤出过程中的流变性能，在研究FDM工艺喷头挤出丝截面形状的基础上，建立了理想轮廓线的补偿模型，并提出了根据挤出丝实际宽度(而非喷嘴孔直径)和零件尺寸实际收缩量补偿零件内、外轮廓的新方法，验证试验结果表明该补偿模型和补偿方法正确可行。 针对FDM快速成型工艺，确定出影响原型件质量的主要工艺参数，通过正交试验，对加工出的27个标准测试件的各种特征进行测量与数据处理，研究了FDM工艺参数对原型件质量的影响规律，进而优化FDM工艺参数，并形成了一套完整的基于参数优化设置的FDM成型工艺规程。 继FDM工艺精度研究后，开展了快速模具制造技术的研究，建立了基于FDM原型快速制造电加工电极的工艺。该工艺将脉冲电铸和电弧喷涂紫铜背衬相结合，获得了结晶致密的电极工作层和结合强度高、导电与导热性良好的电极背衬层，得到的电极达到了常规机加工紫铜电极的电加工性能。同时，该工艺有效地缩短和降低了模具制造周期和成本。 最后，针对目前国内市场应用较普遍的分层实体制造(LOM)快速成型设备，提出了基于特殊涂料喷涂法的LOM纸质原型封闭处理新技术，通过快速化学镀铜解决了LOM纸质原型导电化的难题，建立了基于LOM纸质原型快速制造电加工电极的工艺。该工艺不仅减少了工序，还避免了因翻制过渡模型带来的转换误差，将脉冲电铸和电弧 摘要喷涂紫铜背村相结合制造电极，能保证电极的电加工性能，可以实现高效率、高精度和低成本的快速模具制造。更多还原

【Abstract】 In increasingly stinging market competition, the lead-time to market of new product has become crucial. Therefore, development and fabrication period of new product must be shortened as possible, in order to adapt modern manufacturing mode characterized by low volume, many types and swift change. Rapid Prototyping Manufacturing (RPM) and Rapid Tooling (RT) can rapidly fabricate complicated prototypes and various mould & dies of higher dimensional precision and better surface roughness respectively. With those technologies, the objective of Rapid Product Development (RPD) can be achieved consequently.Fused Deposition Modeling (FDM) has successfully been applied in rapid fabrication of prototype. Combined with traditional mould & die manufacturing technologies, when FDM is used to rapidly fabricate plastic injection mould and EDM electrode, the dimensional, geometrical precision and surface roughnesses of FDM prototype have decisive effects on quality of final product. It is necessary that the precision of FDM process be studied.Firstly, the structures and properties of ABS resin, a kind of material for FDM process, are introduced, and Theological properties of melted ABS filament during extrusion from FDM’s nozzle are studied in viscosity and elasticity, the research results can provide theoretical guidance for establishing the compensation model of ideal contour line.After systemically analyzing the precision of FDM process, the research contents of FDM precision are given, which include material shrinkage during prototyping and its compensation, the compensation of ideal contour line induced by nozzle, and FDM process parameter optimization.The effects of ABS resin shrinkage during prototyping on dimensional precision of workpiece and the method of control and compensation over shrinkage have been studied theoretically and experimentally.According to the rheological properties of melted ABS filament during extrusion from FDM’s nozzle, on the basis of research on extruded filament section shape, the compensation model of ideal contour line is established, and a new technique for compensating inner or outer contour line of workpiece is put forward, which should depend on the real width of extruded filament (instead of nozzle radius) and the real dimensional shrinkage of workpiece. The experimentally validated results prove that the compensation model of ideal contour line and the compensation technique forinABSTRACTcontour line of workpiece are correct and feasible.The main process parameters influencing FDM prototype quality are determined. By Taguchi experiment, various features data of the 27 prototyped standard test part are measured and treated, the effects of FDM process parameters on the quality of prototype are investigated, and FDM process parameters are optimized, thus, a set of FDM prototyping process rules based on parameter optimization is presented.After studying the precision of FDM process, a rapid EDM electrode fabrication technology based on FDM is developed, The technology, which combined pulse-reverse electroforming with strengthening of copper wire-arc spraying, can obtained compact crystal electrode’s working part, and strengthened filling part which has big adhesion strength, better electricity and heat conductivity, The EDM performance of the obtained electrode reaches that of electrolysis copper electrode. At the same time, the technology effectively shortens the manufacturing period and reduces the cost.Finally, aimed at Laminated Object Manufacturing (LOM) machine which is widely applied in domestic market, a new technique for covering LOM prototype with special coating spraying is put forward, the problem on metallization of LOM prototype is resolved by means of rapid electroless plating copper, a rapid EDM electrode fabrication technology based on LOM is established. The technology not only reduces working procedure but avoids conversion errors caused by making transition model, and can ensure EDM performance of the obtained electrode using the comb更多还原