Optimal design of the roll shape for the roll-to-roll forming process of metal micro-patterns

Recently, the roll-to-roll (R2R) forming process has been employed in the manufacturing of micro-patterns for various electronic devices. While previous R2R forming stuides have mainly been applied to the micro-patterning on polymer films, the present study covers the R2R forming process of micro-patterns on a thin metal sheet. It is known that the wrinkling defects can be observed in the metal R2R forming process because the micro-dimples are formed by plastic deformation, which requires an adequate design of the forming roll to ensure a uniform material flow of the metal sheet. In this study, finite element (FE) analyses of the R2R process were applied to predict the material flow during the forming process from which the possibility of wrinkling can be estimated. Statistical analyses were performed from the FE analysis results by combining the design of experiments (DOE) and the response surface method (RSM). The roll shape was then optimized to get a uniform material flow, from which the wrinkling defects can be resolved.