目前主流金属增材制造技术在太空领域存在设备体积较大、搭载成本较高等问题，且国外对此技术进行技术封锁。因此本文提出了一种设备体积小、搭载成本低，仅靠电流为能量源的焦耳热熔丝增材制造技术(Joule Heat Melt Wire Addictive Manufacture，JHAM)，为金属增材制造应用在太空领域提供一种新的方法。本文针对JHAM整个过程中电生热的速度过快，导致温度变化迅速且难以监测的问题，建立了JHAM有限元模型，分析了单道单层和单道多层过程中热-电场的分布及演变过程，实现了热-电场的可视化分析，探究了其产热机制；然后利用验证后的有限元模型，揭示了工艺参数对单道单层和单道多层热-电场变化的影响规律。主要工作内容如下：

首先，根据实验原理和设备结构阐述了在各个物理场中选用的接触类型方法，创建了焦耳热熔丝增材制造三维模型，分析了焦耳热熔丝增材制造过程中所涉及到的热-电-结构三场耦合理论和接触理论，并进行了材料属性赋予、网格划分、分析步设置和边界条件等必要设置，最终建立了基于热-电-结构三场耦合的焦耳热熔丝增材制造单道单层和单道多层有限元模型。

其次，根据所建立的焦耳热熔丝增材制造单道单层有限元模型，分别对方形丝材和圆形丝材的单道单层过程进行热-电场分析。结果表明，高温集中区域位于辊轮正下方丝材与基板接触区域，且单层丝材内部温度分布呈“拱桥”状，基板内部温度分布呈“半椭球”状；在相同的工艺参数下，圆形丝材较方形丝材能量利用率高，且最终成形厚度也较高，故确定了后续分析的研究对象为圆形丝材；然后通过单道单层实验对比了模型中制造过程电势变化和单道熔化区域，验证了所建立的单道单层模型，并利用验证后的模型探究工艺参数对热-电场的影响规律，为实验稳定单道单层提供了理论基础与指导。

最后，在单道单层热-电场分析的基础上对单道多层过程进行热-电场分析。结果表明，单道多层随着层数的增加，从单道3层开始，整个多层丝材内部的温度分布从“拱桥”状逐渐过渡为“象牙”状，其主要原因是多层的传热路径和单层不同；通过对比制造过程中电势变化对单道多层模型进行实验验证，并利用验证后的模型探究工艺参数对热-电场的影响规律，为实验稳定单道多层提供了理论基础与指导。

At present, the mainstream metal additive manufacturing technology in the field of space exists in a large equipment size, the cost of piggyback is higher, and foreign countries had a technical embargo on this technology. Therefore, this paper proposed a Joule Heat Melt Wire Addictive Manufacture (JHAM) technology with small equipment size and low on-board cost, which only relies on electric current as the energy source, to provide a new method for the application of metal additive manufacturing in the space field. In this paper, in response to the problem that the speed of electric heat generation in the whole process of JHAM was too fast, which lead to rapid temperature changes and was difficult to monitor, a finite element model of JHAM was established to analyze the distribution and evolution of the heat-electric field in the process of single-pass monolayer and single-pass multilayer, and to realize the visual analysis of the heat-electric field and explore the heat generation mechanism; and then, the validated finite element model was used to reveal the influence of process parameters on the heat-electric field of the single pass monolayer and single pass multilayer, which was a new approach for metal additive manufacturing applications in the space field. Then, the influence of process parameters on the variation of single-pass single-layer and single-pass multi-layer thermal-electric fields was revealed using the validated finite element model. The main contents of the work are as follows:

Firstly, the whole JHAM process is analyzed theoretically, and the coupling theory and contact theory involved in the three physical fields of heat-electricity-structure are discussed, and the principle of choosing the type of contact in each physical field is elaborated. According to the experimental principles and equipment for JHAM three-dimensional modeling, and without affecting the analysis results of the premise of the appropriate simplification, and then this three-dimensional model for the material properties of the endowment, mesh division, the analysis of the step settings and boundary conditions, and ultimately established based on the thermal-electrical-structural three-field coupling of the JHAM of single-channel single-layer and single-channel multilayer finite element model.

After that, according to the established single-pass single-layer finite element model of JHAM, the single-pass single-layer process was analyzed for two shapes of square and round wire materials. The results show that the heat-producing area is located in the contact area between the filament and the substrate directly under the roller, and the temperature distribution inside the single-layer filament is in the shape of "arch bridge", and the temperature distribution inside the substrate is in the shape of "semi-ellipsoid"; and under the same process parameters, the energy utilization rate of round filament is higher than that of square filament, and the final forming height is higher than that of square filament. And under the same process parameters, the energy utilization rate of round wire material is higher than that of square wire material, and the final forming height is also better, so it is determined that the research object of the subsequent analysis is round wire material; then the established single-channel monolayer model is verified by comparing the change of electric potential of the process and the single-channel melting area; and the verified model is used to investigate the influence of process parameters on the thermal-electric field law, which provides the theoretical basis and guidance for the experimental stabilization of the single-channel monolayer.

Finally, the thermal-electric field analysis of the single-pass multilayer process was carried out based on the thermal-electric field analysis of the single-pass monolayer. The results show that, with the increase of the number of layers in the single-pass multilayer, the temperature distribution inside the multilayer starts from 3 layers in the single-pass multilayer and gradually transitions from an "arch bridge" shape to an "ivory" shape, which is mainly due to the different heat transfer paths of the multilayer and the single layer; the single-pass multilayer model is experimentally validated by comparing the electric potential change in the fabrication process. By comparing the change of electric potential in the manufacturing process, we experimentally validate the single-pass multilayer model, and use the validated model to investigate the influence of process parameters on the thermal-electric field, which provides a theoretical basis and guidance for experimentally stabilizing the single-pass multilayer.