复杂形状金属零件的等离子熔积无模成形路径规划-数字化材料成形专业论文.docxVIP

II II Abstract PDM(Plasma Deposition Manufacturing) is a new technology, which is based on Rapid Prototyping and can directly and rapidly fabricate functional metal parts having high intensity and full density by plasma high energy density beam. PDM has some advantages: high forming efficiency, low cost, good machining flexibility, diversiform kinds of material powder, unlimited shape and size and so on. Plasma deposition direct manufacturing of metal parts is restricted within narrow practical scope by the problem of low shape complexity and unfeasibility of adding support structures, which also exists in other direct metal prototyping technologies using high energy beams. In recent years, The research hotspot of LM (Layered Manufacturing) has shifted to directly manufacturing of metal parts using multi-axies (3-axies、5-axies etc) simultaneous motion, via which the problem of forming complex shape metal parts without support structure can be overcome effectively. The 5-Aixis Plasma Deposition Multi-direction Directly Manufacturing System, which combines technologies of Rapid Prototyping, CAD/CAM, Numerical Control and Multi-Direction Layered Deposition is studied in this paper. The system has the ability of depositing material along multiple directions. It can not only get good quality while forming, but also be able to directly manufacture complex shape metal parts without support structures. Based on the STL model, the basic theory of five-Aixes Plasma Deposition Multi-direction Directly Manufacturing System is studied in this paper. The key issue is part decomposition. Through virtual interactive interface, complex shape metal part with overhanging features was decomposed into smaller sub-volumes, each of which can be completely built along a certain direction. In the ideal case part decomposition enables support-less fabrication. A task framework for multi-direction layered manufacturing is proposed. Key issues including the feature recognition of complex parts