快速熔模铸造零件的拓扑设计与分析研究

发布时间：2018-08-19 16:55

【摘要】：快速熔模铸造(Rapid Investment Casting,RIC)是3D打印技术与熔模铸造相结合而形成的一种间接增材制造金属零件的生产工艺,它相对于直接增材制造具有工艺成熟、成本低、材料不限、可制造大尺寸零件、不需去除支撑等优势。同时,它也与直接增材制造一样,能够制造轻量化的复杂拓扑结构零件。过去的常规结构零件受限于传统的减材制造方法,未能更好的进行拓扑设计,包括基于优化算法的拓扑优化设计以及基于经验知识的晶格化设计。对传统结构零件重新进行拓扑设计,将会充分发挥RIC工艺的潜能,推动产品设计与制造模式的变革。本文面向快速熔模铸造工艺所生产的零件,对其拓扑设计(CAD)、结构分析(CAE)以及铸造工艺分析(CACE,Computer Aided Casting Engineering)进行研究,期望探索一种CAD/CAE/CACE集成化方法。主要研究内容如下:第一,面向RIC的拓扑优化设计与分析研究。为了提高RIC零件的拓扑优化设计效率,提出了一种集成化的拓扑优化设计方法,并通过机器人抓手拓扑优化设计实例进行了具体说明;然后采用该方法对飞机上的某轴承支架进行了拓扑优化设计。第二,面向RIC的晶格拓扑设计与分析研究。对航空航天领域的点阵夹芯结构进行了参数分析,并对点阵夹芯结构进行了晶格拓扑设计和分析,然后将晶格结构用于涡轮叶片的拓扑设计中,得到了三种芯子形式的晶格结构涡轮叶片,通过有限元分析表明了该结构具有更高的综合热力学性能。第三,RIC零件的熔模铸造仿真分析研究。将飞机上某轴承支架和金字塔点阵夹芯结构分别作为拓扑优化和晶格结构拓扑设计的例子,采用ProCAST软件对充型、凝固过程进行了仿真分析,并通过缺陷分析对缩孔缩松进行了预测。通过分析复杂RIC零件的可铸造工艺条件,为其铸造工艺选择提供了借鉴。
[Abstract]:Rapid investment casting (Rapid Investment casting) is a kind of production technology of metal parts which is formed by the combination of 3D printing technology and investment casting. It has the advantages of mature process, low cost and unlimited material compared with direct material increasing manufacture. Large-size parts can be manufactured without the need to remove support and other advantages. At the same time, it can also be used to manufacture lightweight and complex topological parts, just like direct material adding manufacturing. In the past, the conventional structural parts were limited by the traditional method of material reduction, and failed to do better topology design, including topology optimization based on optimization algorithm and lattice design based on empirical knowledge. Redesigning the topology of traditional structural parts will give full play to the potential of RIC process and promote the innovation of product design and manufacturing mode. In this paper, the topological design of (CAD), structure analysis (CAE) and casting process analysis computer Aided Casting Engineering) are studied for the parts produced by rapid investment casting process. It is expected to explore a method of CAD/CAE/CACE integration. The main contents are as follows: first, topology optimization design and analysis for RIC. In order to improve the efficiency of topology optimization design of RIC parts, an integrated topology optimization design method is proposed and illustrated by an example of robot gripper topology optimization design. Then the method is used to optimize the topology of a bearing support on an aircraft. Second, the design and analysis of lattice topology for RIC. The lattice sandwich structure in aerospace field is analyzed, and the lattice topology is designed and analyzed. Then the lattice structure is applied to the topology design of turbine blade. Three kinds of core structure turbine blades are obtained. The finite element analysis shows that the structure has higher comprehensive thermodynamic performance. The third part of RIC simulation analysis of investment casting. A bearing bracket and a pyramid lattice sandwich structure are used as examples of topology optimization and lattice topology design respectively. The mold filling and solidification process are simulated by ProCAST software. The shrinkage porosity was predicted by defect analysis. By analyzing the casting process conditions of complex RIC parts, this paper provides a reference for the selection of casting process.
【学位授予单位】：南京航空航天大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TG249.5

【参考文献】