基于激光选区熔化技术的个性化植入体设计与直接制造研究

发布时间：2018-02-14 05:25

本文关键词： 激光选区熔化（SLM）个性化植入体数字化设计直接制造　出处：《华南理工大学》2014年博士论文　论文类型：学位论文

【摘要】：增材制造作为一种新的制造技术，正快速改变我们的生活方式。激光选区熔化技术（Selective laser metling，SLM）是增材制造中直接制造金属功能件的重要技术之一。通过SLM技术，可以获得任意复杂形状、力学性能良好、尺寸精度较高的功能件，适合在小批量、定制化的复杂功能件上应用，特别是为患者量身定做个性化植入体。目前对SLM研究大多集中在设备、材料、工艺等方面，而由新的制造技术对设计改变与影响的研究相对较少。为了充分利用SLM技术在个性化植入体直接制造方面的优势，基于SLM技术对个性化植入体进行设计与制造是非常有意义的研究。据此，本文研究基于激光选区熔化的个性化植入体设计与制造，主要研究内容和成果如下：（1）提出了SLM自由结构设计规则。基于增材制造共性知识—结构自由生长概念，衍生了自由结构的设计与制造。以自由结构和传统设计公理体系构建了基于SLM自由结构的设计规则，并研究了结构设计约束—原理约束、工具约束、应用约束。基于SLM自由结构的设计规则，对个性化植入体的设计规则进行了探讨，提出个性化植入体设计中两大应用约束—形状个性化匹配性约束、性能近似性约束。（2）研究了个性化植入体设计方法。在基于SLM自由结构的设计体系下，以个性化几何外形的匹配为约束，采用正向、逆向设计方法对个性化植入体基本结构进行设计。以结构性能与宿主组织近似性为约束，采用以多孔结构为性能结构，与几何外形进行整体或者局部组合设计，完成个性化植入体性能优化设计。同时为了提高设计效率，采用基于实例推理方式，先匹配与患者需求的近似植入体，在对其部分结构进行变型设计的方式满足个性化要求。（3）基于SLM熔道堆积理论，研究成型工艺基本单元-熔道形貌影响因素，以及熔道层内搭接以及层间搭接率对成型致密度的影响，建立了材料工艺研究通用机理。对医用金属材料316L不锈钢、CoCrMo、Ti6Al4V成型工艺研究，获得高致密度以及连续致密度成型工艺参数。在高致密度工艺参数下成型测试样件，对成型性能、耐腐性、几何性能进行测试研究。结果证实，医用金属材料316L不锈钢、CoCrMo、Ti6Al4V的SLM性能均高于医用铸造件水平，可以满足医用产品要求。（4）为了提高对个性化植入体设计与制造的响应能力，在网络化制造基础上，建立个性化植入体协同设计与制造方法。个性化植入体设计与制造需要医生、设计人员、制造人员、分析人员、工艺人员进行信息交流，才能完成个性化植入体设计与制造任务。为了更快、更好地实现个性化植入体的设计与制造，，采用网络化制造方式，设计与制造任务中组织人员通过协同的方式完成信息交流。整个协同过程中，通过人员组织管理、知识管理、协同感知管理、协同冲突管理等保证协同过程顺利进行，从而解决了个性化植入体设计与制造响应慢的问题。
[Abstract]:As a new manufacturing technology, material augmentation is rapidly changing our way of life. Laser selective laser Metalingling (SLM) is one of the most important technologies in fabricating metal functional parts directly through SLM technology. Can obtain any complex shape, good mechanical properties, high dimensional accuracy of functional parts, suitable for small batch, customized complex functional applications, In particular, personalized implants are tailored for patients. At present, most of the research on SLM is focused on equipment, materials, technology, and so on. In order to make full use of the advantages of SLM technology in the direct manufacture of individualized implants, The design and manufacture of personalized implants based on SLM technology is very meaningful. Therefore, the design and manufacture of individualized implants based on laser selective melting are studied in this paper. The main research contents and results are as follows:. (1) the SLM free structure design rule is put forward. Based on the common knowledge of adding material manufacturing, the concept of free structure growth is proposed. The design and manufacture of free structure are derived. The design rules based on free structure and traditional design axiom system are constructed, and the structure design constraint-principle constraint and tool constraint are studied. Application constraints. Based on the design rules of SLM free structure, the design rules of personalized implants are discussed, and two major application constraints in personalized implant design, namely, shape personalized matching constraints and performance approximation constraints, are proposed. (2) the design method of individualized implant is studied. In the design system based on SLM free structure, the matching of individual geometry is taken as the constraint and the forward direction is adopted. The basic structure of individualized implants is designed by reverse design. The structural performance is constrained by the approximation of host tissue, the porous structure is used as the performance structure, and the whole or local combination design is carried out with geometric shape. At the same time, in order to improve the design efficiency, we adopt case-based reasoning (CBR) to match the approximate implants with patients' needs, and design some of its structures to meet the requirements of personalization. (3) based on the theory of SLM melt path accumulation, the factors affecting the morphology of the melt channel, the basic unit of the forming process, and the influence of the overlap ratio between the layers and within the channel layer on the density of the forming process are studied. The general mechanism of material technology research was established. The processing parameters of high density and continuous density forming of medical metal material 316L stainless steel CoCrMoTi6Al4V were obtained. The results show that the SLM properties of medical metal material 316L stainless steel CoCrMoMoTi6Al4V are higher than those of medical castings, which can meet the requirements of medical products. In order to improve the ability of responding to the design and manufacture of individualized implants, a collaborative design and manufacturing method of individualized implants is established on the basis of networked manufacturing. The design and manufacture of individualized implants need doctors, designers and manufacturers. In order to realize the design and manufacture of individualized implants more quickly and better, the design and manufacture of individualized implants can be accomplished by means of networked manufacturing in order to exchange information between analysts and craftsmen. In the design and manufacturing task, the organization personnel complete the information exchange through the cooperative way. In the whole collaborative process, the cooperation process is ensured by the personnel organization management, knowledge management, cooperative perception management, collaborative conflict management, etc. Thus, the problem of slow response in the design and manufacture of personalized implants is solved.
【学位授予单位】：华南理工大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TH16

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