Optimization of cushion conditions in micro multi-point sheet forming

Improvement of product quality is required more than ever for mass production of micro formed parts. The process of micro multi-point forming with cushion has been simulated in this paper by finite element model which incorporates a constitutive relation with consideration of size effect. The effect of the cushion material, cushion thickness and coefficient of friction on the surface quality of the deformed sheet has been investigated. It has been found that a proper selection of the cushion material and optimum cushion thickness can significantly improve the surface quality. In addition, this paper also discusses the influence of the cushion material and coefficient of friction on the sheet thickness distribution. Better surface quality and thickness distribution can be obtained with good lubricating condition.