| 摘要: | 積層製造近年興盛崛起，尤其在需求高強度，高機械性能的金屬應用場合，能適用金屬材料的粉床熔融成型和指向性能量沈積技術尤其受到矚目，但成本仍為積層製造普及化的障礙。熔融燒結製程所使用之金屬粉末，由於設備成本高，粉末品質之要求高，製作不易，售價居高不下，是積層製造成本難以抑低的一項重要因素。而金屬粉床熔融成型製程之進行，卻極容易形成粉末浪費。在降低成本之觀點，減少粉末消耗量，將原先製程中會直接丟棄的粉末處理回收循環使用，遂成為一重要技術手法，值得產業與學界合作進行研發。
前行研究[1,2]完成自動化粉末回收系統設備之開發，整合四個子系統，涵蓋氣體輸送、粉末供應、粉末篩分以及人機介面，後續仍需有粉末處理方面設備加入系統，並將粉末回送至積層製造主機，始能構成完整之粉末回收處理系統。而這裏新增粉末處理設備中，主要即為混合器和串聯各設備的輸送設備。本研究著重在整體粉末回收系統的整合與串接，完成並應證整體系統的可用性，使粉末回收處理系統可在金屬粉末積層製造整體系統順利發揮作用。
執行面依系統設計概念形成方塊流程圖和程序流程圖，以及加入製程所需設備、控制元件、閥門產出管線儀控圖。進而依圖選取系統中所需各項零組件，並規劃製程產出回收處理系統動作順序與警報通知、金屬粉末回收處理系統閥門運作流程。確認流程之後，產出工程圖與電路圖。最後，以數值模擬分析混合器進氣口之傾斜角度、高度、據中心距離以及進氣速度，尋出最佳混合器結構及操作進氣速度，完成混合器優化。
;Additive manufacturing (AM) has been booming in recent years, and it can be regarded as the key technology in the third industrial revolution. Among which, PBF (Powder Bed Fusion) and DED (Directed Energy Deposition) technologies that can be applied to metal parts production are particularly attracting attention in the case that mechanical properties are of high importance. But the cost is still an obstacle to the popularity of additive manufacturing. The metal powder used in AM process is an important factor results in difficult cost-down of AM due to the expensive equipment, high powder quality requirements, difficult production procedure, and then comes the extremely high powder price as a results. On the other hand, the metal PBF process tends easy to waste powder. For the purpose of cutting costs, reducing powder consumption by recycling the powder that was directly discarded in the original manufacturing process has become a high potential technique worthy of researches in innovation.
The previous researches [1,2] completed the development of automated powder recovery system equipment, including four subsystems, pneumatic conveying, powder supply, powder screening, and human-machine interface. Besides that, there still needs powder processing equipment to be added into the system to accomplish a complete powder recovery system that capable to recycle powder back to the AM machine. The new powder processing equipment here is the mixer and the powder conveying equipment connecting equipment together in series. The current research focuses on the integration and link all units of the powder recovery system that can work smoothly together in the additive manufacturing system.
While in the execution of design work, a block flow chart and process flow chart were made firstly. Then the operation units, controlling instrument, valves are put into process flow chart to form the piping and instrumentation diagram required for the process. After choosing the equipment and arrange the processing sequence, alarm system for this powder recycling system, then valves operation sequence diagram can be made. After confirming these objects, the engineering drawing and electrical drawing can be made. The performance of the mixer can be simulated with different air inlet angles, height, latent distance from symmetric plane, and the operation air inlet speed as parameters to get the optimized structure and operation condition of the mixer. |
