전해-자기 복합가공을 이용한 연료전지 분리판의 마이크로 채널 디버링

Abstract

A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent. Proton exchange membrane fuel cell(PEMFC) has many advantages which are environment-friendly energy source, high efficiency of generation, non-noise and mobility. Stainless steel bipolar plates for PEMFC offer many advantages over conventional graphitic materials. These include relative low cost, high strength, easy of manufacture and as they can be shaped into thin sheets, significant improvement in the power/volume ratio. However, the manufacturing of metal bipolar plate using micro-end mill occur the burr from workpiece. By a fuel gas leak and the disturbance of flow of hydrogen and oxygen, occurred burr degrades efficiency and performance and thus the manufacture of metal bipolar plate is demanded deburring process as a finishing process. In this study, deburring process using EP-MAP hybrid process was proposed. The EP-MAP hybrid process is expected to machine complex and hardened materials. For this reason, The EP-MAP deburring process was applied to micro channel in bipolar plate, thereby it can obtain both deburring process and polishing process. The EP-MAP deburring process on the micro channel for bipolar plate was performed. Through design of experiment method and RSM method, the tendency toward the surface roughness of channel and error of height according to process parameter after EP-MAP deburring process was analyzed. Surface roughness and error of height of micro channel after the EP-MAP hybrid deburring process showed a tendency to be improved with the increasing of feed rate, increasing of working gap and deceasing of magnetic flux density. And, when a electric potential was 10V, both the superior surface roughness and lower error of height was acquired. Therefore, it seems that the level 1 parameter A(magnetic flux density) and level 2 parameter B(electric potential) and level 3 parameter C(working gap), D(feed rate) may provide optimum result of EP-MAP hybrid deburring process.