新型高靜水壓(微)成形機台及其應用製程之研究

Abstract

近年來隨著半導體及電子產品的微小化，微結構之成形及精度備受重視。相較於傳統沖壓技術，靜水壓成形技術具有成形高深寬比之薄板金工件的優勢，然而高靜水壓成形機台之製造仍存在許多技術瓶頸，故高靜水壓成形之技術及其應用仍少有研究。本計畫擬研發一高靜水壓成形機台，並將此高靜水壓成形技術應用於燃料電池以及平板式熱管之關鍵零組件上。 本計畫將針對此新型高靜水壓成形之機台及應用製程，預定進行全程三年之研究： 第一年將針對高靜水壓微薄板金成形之製程需求，進行設計並製造出可提供1000MPa工作壓力之試驗機台，後續針對此機台做初步之測試，並完成高靜水壓成形機台之成形能力試驗，針對各種微結構成形之基本參數如金屬板厚度、微流道之寬度、深度、流道間距、成形壓力、持壓時間等進行初步探討，驗證高靜水壓機台之加工特性及能力。 第二年將根據第一年之成果建構出精準的高靜水壓成形有限元素模擬模組，並配合最佳化軟體完成一具有分析最佳參數能力之完整設計系統，並將此技術用於設計小型可攜式質子交換膜燃料電池及固態氧化物燃料電池之雙極板成形，並配合設計製造(微放電加工)之適當模具，以高靜水壓成形實作出具微流道結構之不銹鋼薄雙極板，最後對實際組裝此雙極板之燃料電池進行性能測試。 第三年根據前二年之研究方法與成果，將此技術應用於一般平板式及平板式輻射狀熱管之研究，透過高靜水壓成形實驗、有限元素分析以及最佳化分析，針對各種成形參數，如之金屬板金材料(紅銅、鋁)、溝槽幾何外形和數量以及毛細結構之深寬比來得出最佳之參數組合。最後實作並測試高靜水壓成形製作之平板式熱管的熱傳性能。

Recently, semiconductor and electronics have been becoming smaller and denser, and micro-fabrication techniques and dimension precision of workpieces have become more important. Compared with stamping technique, hydroforming has advantages on forming thin sheets with high aspect ratio. However, there still exist some problems in building high pressure hydroforming device and only few researches about high pressure hydroforming technique have been released. Therefore, a novel and patented high pressure hydroforming machine will be developed and applied to form both micro flow channels on metal bipolar plates for fuel cells and capillary structures for plate heat pipes in this proposal. Scheduled for totally three years, this proposal will accomplish the following tasks: In the first year, the research will focus on the basics of high pressure hydroforming process. A novel apparatus which can offer 1000MPa working pressure will be designed and manufactured. Then, hydroforming experiments will be conducted to test the forming capability of this new apparatus. Forming parameters such as workpiece thickness, width and depth of micro flow channels, channel gap, forming pressure, and the time of holding pressure will be tested. Finally, the forming characteristic and capability of this high pressure hydroforming apparatus will be verified to satisfy the designed specifications. In the second year, according to the results of the first-year research, precise finite element simulation module of high pressure hydroforming process will be established, combined with the optimum software to complete the system which can design and analyze all kinds of optimal forming parameters. And then the micro flow channels on metal bipolar plate for both small portable PEM fuel cells and solid oxide fuel cells will be designed and manufactured by high pressure hydroforming on stainless sheets. The mold used in this process will be machined by micro EDM. Finally, the cell performance of fuel cells with the above thin stainless bipolar plate will be tested. In the third year, with the help of last two years’ research, the high pressure hydroforming technique will be applied to plate heat pipe and radial heat pipe, and several forming parameters such as materials (copper and aluminum), geometries of groove-wick, and aspect ratio of capillary structure will be tested. The finite element analysis and optimum analysis will also be used to seek for the optimal forming parameters. Finally, heat pipes with wick structure will be manufactured by means of high pressure hydroforming, and their performances will be tested.