Numerical Investigation on Effect of Wrinkle on Stiffness in Isotropic Metal Sheets

摘要

A numerical study was conducted to find the effect of wrinkle in a metal sheet on its stiffness under tensile, compressive and flexural loading conditions. To define wrinkle of different sizes in model 'wrinkle factor' - ratio of thickness of specimen at wrinkle location to thickness of the specimen at no wrinkle location, is defined. Stiffness of a sheet with wrinkle has been compared with that of a pristine sheet under various loading conditions. From numerical results it is seen that, the stiffness in both tension and compression loading reduces as the wrinkle factor increases. But the stiffness in flexural loading is not affected considerably; contrary it increases for some wrinkle factor. Considering various loading conditions, it is observed that, stiffness in compression is affected more than in any other case. Furthermore, an attempt has been made to investigate force picked up by wrinkled portion and compared with the total force applied on the sample.