균일한 두께분포를 위한 신장/블로 공정을 이용한 초소성 성형 공정설계 해석

Analysis of Superplastic Forming Process Design Using a Combined Stretch/Blow Process for Uniform Thickness Distribution

A rigid-viscoplastic finite element method has been used for modeling superplastic stretch/blow process design to improve thickness distribution. Punch velocity-time relationship of the stretch forming and pressure-time cycle of the blow forming for a given strain rate are calculated. A superplastic material is assumed to be isotropic and a plane-strain line element based on membrane approximation is employed for the formulation. The effects of the width, corner radius and height of the punch during stretch forming are examined for the final thickness distribution, and the process design to improve thickness distribution can be established.