Fabrication of Metallic Bipolar Plates for Proton Exchange Membrane Fuel Cell by Flexible Forming Process-Numerical Simulations and Experiments

Author(s):  
Linfa Peng ◽  
Dong’an Liu ◽  
Peng Hu ◽  
Xinmin Lai ◽  
Jun Ni

PEM fuel cell nowadays is expensive for widespread commercialization, though it has obvious advantages, such as high efficiency, high power density, fast startup and high system robustness. As one of the most important and costliest components in the PEM fuel cell stack, bipolar plates (BPPs) account for more than 80% of the weight and 30% of the cost of the whole stack. By replacing the conventional graphitic or machined thick metal plates with the lightweight and low-cost thin metallic sheet BPP with sustainable coating, PEM fuel cell will become an attractive choice for manufacturers. In this study, the fabrication of micro-channel features by flexible forming process (FFP) are studied first, which demonstrates the feasibility of using FFP to manufacture thin metallic BPPs. Then, the obtained knowledge is applied onto the fabrication of real thin metallic BPPs with some process amendment. The first investigation of this study focuses on the forming of micro-channel features with 100 μm thickness stainless steel sheet. A finite element analysis (FEA) model is built and key process parameters (hardness of soft tools used in FFP, friction coefficients between contact surfaces) associated with the formability of BPPs are studied. The FEA is partly validated by the experiments. In the second investigation, finite element analysis method is adopted in the design of the BPP forming process. Based on the numerical simulation results, the die setup is prepared and some process amendments are made to improve the formability of BPPs. As a result, high quality metallic BPPs are obtained in the latter experiments, which demonstrates the feasibility to manufacture the metallic bipolar plate by FFP.

2020 ◽  
Vol 2020.28 (0) ◽  
pp. 104
Author(s):  
Riku SUZUKI ◽  
Noboru KATAYAMA ◽  
Kiyoshi DOWAKI ◽  
Shinji OGIHARA

2015 ◽  
Vol 809-810 ◽  
pp. 235-240
Author(s):  
Catalina Maier ◽  
Robin Gauthier

Roller leveling is a forming process which used to minimize flatness imperfection and residual stresses by repeated forming process of a sheet metal. The determination of the machine settings must be very accurate and ask a precise mechanical study. In order to determine an algorithm which can predict the leveling quality according to the machine settings we start by a theoretical model of stress evolution during the process. The plastification ratio is deducted from this one and the values obtained by this approach are compared whit experimental values. The finite element analysis is performed, in second step in order to assure a good accuracy of the prediction algorithm. Theoretical study determines a minimum of the plastification ratio according to the machine settings. The finite element analysis gives more accurate results due to the consideration of different characteristics of the process, neglected by the theoretical model: cumulative effect of bending/unbending with stretching of the sheet during the passing between each couple of rolls, boundary conditions at the limit of the material deformed by two adjoining couples of rolls, friction force.


2018 ◽  
Vol 53 (8) ◽  
pp. 584-601 ◽  
Author(s):  
Sara S Miranda ◽  
Manuel R Barbosa ◽  
Abel D Santos ◽  
J Bessa Pacheco ◽  
Rui L Amaral

Press brake air bending, a process of obtaining products by sheet metal forming, can be considered at first sight a simple geometric problem. However the accuracy of the obtained geometries involves the combination of multiple parameters directly associated with the tools and the processing parameters, as well as with the sheet metal materials and dimensions. The main topic herein presented deals with the capability of predicting the punch displacement process parameter that enables the product to be accurately shaped to a desired bending angle, in press brake air bending. In our approach, it is considered separately the forming process and the elastic recovery (i.e. the springback effect). Current solutions in press brake numerical control (computer numerical control) are normally configured by analytical models developed from geometrical analysis and including correcting factors. In our approach, it is proposed to combine the use of a learning tool, artificial neural networks, with a simulation and data generation tool (finite element analysis). This combination enables modeling the complex nonlinear behavior of the forming process and springback effect, including the validation of results obtained. A developed model taking into account different process parameters and tool geometries allow extending the range of applications with practical interest in industry. The final solution is compatible with its incorporation in a computer numerical control press brake controller. It was concluded that, using this methodology, it is possible to predict efficient and accurate final geometries after bending, being also a step forward to a “first time right” solution. In addition, the developed models, methodologies and obtained results were validated by comparison with experimental tests.


2014 ◽  
Vol 2014.22 (0) ◽  
pp. 163-164
Author(s):  
Shintaro AKANUMA ◽  
Tomoya SUZUKI ◽  
Hayato ASO ◽  
Bunkyo KYO ◽  
Shinichi NISHIDA ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document