基于SLS原理的快速成形机研制

介绍了选择性激光烧结（SLS）快速成形技术的工作原理,简述了基于SIS原理的快速成形机的样机研制与调试、烧结工艺实验、存在的问题及解决思路。     

低碳钢粉末选择性阻焊快速成形工艺研究

以低碳钢粉末选择性阻焊成形含随形水路的注塑模模芯为例,探讨了坡度成形、粉未磁化和梯形效应等问题.提出了电极材料应用不当是导致梯形效应的主要原因.利用排水法对制件致密度进行测量,得出经SRW快速成形工艺的制件,其致密度接近理论致密度的结论.     

基于RPM的产品模型快速开发技术

以某手机外壳模型在AFS-3000型快速成型系统中的成形为例，对选择性激光烧结法（SLS）的具体成形步骤做了描述，介绍了基于RPM的产品模型快速开发技术，为新产品的快速开发提供了强有力的技术支持。     

基于LOM技术的大型原型成形效率分析

如何提高加工效率一直是快速成形（RP）技术的一个重要课题，也是快速成形技术走向大型化的一个主要障碍。通过对几种典型的快速成形工艺的分析、比较，认为分层实体制造（LOM）工艺以面作为最小成形单位，具有最高的成形效率，是RP技术中较适合制造大型原型的工艺。以清华大学激光快速成形中心的SSM-1600成形系统为例，分析了成形大型原型时的工艺特点以及提高成形效率的一些途径。     

快速成形技术的发展

介绍了快速成形（RP）技术的发展状况，具体分析了RP技术的原理和目前应用较多的立体光固化（SLA）、选择性激光烧结（SLS）、分层实体制造（LOM）、熔积成形（FDM）4种RP方法，并结合该技术研究的最新进展，提出了未来的发展趋势。     

用选择性激光烧结实现快速精密铸造

研究用选择性激光烧结（ＳＬＳ）实现快速铸造的方法和工艺。结果表明，将快速成形与精密铸造结合可以不用模具而获得复杂的铸件，同时降低小批量产品的生产周期和成本，使设计、修改、验证和制造同步。通过若干实例说明快速铸造的特点．     

直接金属沉积成形工艺的RP软件研究

直接金属沉积（DMD）快速成形是快速制造的一种新工艺，其原理与传统的快速成形工艺（如分层实体制造SSM，熔融挤压成形MEM，立体光刻SLA等）相同。所介绍的直接金属沉积成形工艺是在CAD模型直接驱动下，由高功率激光熔化同轴输送的金属粉末，层层扫描熔化堆积，直接形成致密的金属零件，该直接金属成形系统包括数控系统，激光系统，同轴送粉系统，RP数据处理软件系统，控制软件系统等，重点针对高功率激光同轴送粉的真空金属沉积成形工艺，研究相应的控制软件开发和数据处理软件的改进。     

快速成形技术在仿生支架制造中的应用

快速成形方法有很多种,包括立体光刻法/微立体光刻技术、分层实体法、选择性激光烧结法、熔融沉积法和三维打印法,不同的快速成形方法具有不同的特点,在加工仿生支架过程中,它们采用不同的成形材料、成形工艺以及后处理。文中介绍了不同快速成形方法制作仿生支架的工艺过程,并比较了它们的优点和缺点。     

选择性激光烧结金属件精度和密度的研究

金属件成形精度和密度是快速成形技术在工业应用中的关键问题之一。通过对覆膜金属粉末选择性激光烧结 ,研究了激光烧结工艺参数激光功率、扫描速度、扫描间距、单层层厚 ,烧结体厚度对金属件成形精度和密度的影响关系 ,并得出了一个分析 X、Y轴方向尺寸误差的定性公式 ,给出了烧结工艺参数优化的方法 ,而且优化了一组烧结工艺参数 ,用此工艺参数成功烧制出金属原型件     

骨组织工程细胞载体框架的两种快速成形新工艺

采用纳米羟基磷石灰石／胶原自组装材料，同时在成形过程中加入聚左旋乳酸以改善的成形性能，开发了两种新的制备骨组织工程细腻载体框架结构的快速成形工艺：T（组织工程材料）＋F（框架成形材料）成形工艺和低温喷射成形工艺。这两种工艺实现了材料的精确堆积，能成形200－500μm的可控大孔隙和孔隙梯度结构，获得理想的形态参数。     

激光选区快速成型件后处理工艺的试验研究

快速成型技术就是直接根据CAD模型,快速生产样件或零件的成组技术总称[1],它是先进制造技术的重要组成部分.本文主要介绍了激光选区粉末烧结(SLS)技术的原理,并结合工业生产,研究了SLS快速成型件的后处理工艺,为激光选区粉末烧结快速成型技术的进一步应用打下了良好的基础.     

Positional correction algorithm of a laser galvanometric scanning system used in rapid prototyping manufacturing

The laser galvanometric scanning technique has brought rapid prototyping manufacturing into a new era. However, a number of errors severely affect the prototyping accuracy of the work piece. This paper gives a detailed analysis of the errors involved in the galvanometric scanning system used in rapid prototyping manufacturing. A positional correction algorithm has been developed to rectify the errors to meet the precision requirements of the processing. Experimental results based on a selective laser stinting (SLS) machine prove the efficiency of the positional correction algorithm.     

SLS快速成形技术中激光加工参数对制件性能的影响

以AFS--320MZ快速成形机为例，研究了基于选择性激光烧结(SLS)快速成形制造中激光功率密度、扫描速度、扫描间距、扫描方式和铺粉密度等加工参数对制件性能的影响。     

变长线快速成形机的结构设计

介绍一种选择性激光烧结变长线快速成形机的结构设计。阐述变长线激光扫描快速成形机的工作原理，主要结构组成，结构设计的主要特点，激光变长线扫描快速成形机具有成形尺寸大，效率高的优点。烧结实验证明，变长线快速成形的结构设计合理，具有较好的应用前景。     

选择性激光烧结工艺参数智能优化方法研究

将专家系统 (Expert System,ES)和神经网络 (Artificial Neural Network,ANN)结合起来以优化选择性激光烧结 (Selective L aser Sintering,SL S)快速成形工艺参数。根据 SL S的工艺特点 ,选择了一种适合 SL S工艺参数优化的 BP网络模型 ,并对其结构和有关参数的选取进行了详细的设计和讨论。在此基础上开发成功的神经网络专家系统已应用于 SL S制件收缩补偿系数的自动优化中 ,取得了良好的效果。     

Implementation of a Robot System for Sculptured Surface Cutting. Part 2. Finish Machining

Rapid prototyping plays an important role in product development. There are two ways to realise rapid prototyping: one is to develop new prototyping equipment such as stereolithography apparatus (SLA), selective laser sintering (SLS), etc., and the other is to improve existing CNC techniques. In this work, a robot system for rapid prototyping, which is an enhancement of the CNC based method, is presented. A robot arm holding a milling tool is used to machine the prototype of a solid model drawn using a commercial CAD system. In a previous paper, Part 1, a strategy using the robot for rough machining was discussed and then an automatic tool-path generation method using a grid height array was presented. As a verification of the proposed algorithm, a number of prototypes were produced, which demonstrated the feasibility and advantages of the algorithm. In this paper, Part 2, an approach to represent C-space by incorporating possible variations in tooling orientations is proposed. In order to reduce the error on complex surfaces resulting from undercut or overcut operations, a curvature-matching algorithm is also developed. Finally, experimental work using collsion-free planning for manipulator movement and stimulation for the curvature matching algorithm is carried out.     

Optimizing process parameters for selective laser sintering based on neural network and genetic algorithm

Selective laser sintering (SLS) is an attractive rapid prototyping (RP) technology capable of manufacturing parts from a variety of materials. However, the wider application of SLS has been limited, due to their accuracy. This paper presents an optimal method to determine the best processing parameter for SLS by minimizing the shrinkage. According to the nonlinear and multitudinous processing parameter feature of SLS, the theory and the algorithms of the neural network are applied for studying SLS process parameters. The process is modeled and described by neural network based on experiment. Moreover, the optimum process parameters, such as layer thickness, hatch spacing, laser power, scanning speed, work surroundings temperature, interval time, and scanning mode are obtained by adopting the genetic algorithm based on the neural network model. The optimum process parameters will be benefit for RP users in creating RP parts with a higher level of accuracy.     

直接金属成形件的性能研究

直接金属成形技术是快速成形领域研究的热点问题，文中提出一种基于弧焊的直接金属成形技术，并对基于该技术制作的成形件进行性能评测，对成形件进行密度、强度与硬度指标测试和金相组织观察表明，基于弧焊的直接金属成形件的组织结构和力学性能指标明显优于SLS（selective laser simering）工艺成形件，达到或高于铸造零件；异种材料成形时化学成分、物理性能、组织特点的差异对成形件的性能有不利影响。     

Generation of an STL File from 3D Measurement Data with User-Controlled Data Reduction

Reverse engineering is a methodology for constructing com-puter- aided design (CAD) models of physical parts by digitising an existing part, creating a computer model and then using it to manufacture the component. When a digitised part is to be manufactured by means of rapid prototyping machines such as stereolithography apparatus (SLA) and selective laser sintering equipment (SLS), etc., it is not necessary to construct the CAD model of a digitised part. This can be achieved by the proposed novel method which can construct an STL file (the de facto file format for rapid prototyping machines) directly from digitised part data. Furthermore, the STL file can be constructed with a significant data reduction at the users’ discretion.