| Abstract: | This paper focuses on several aspects of drawability, including the interactions between material parameters, operating temperatures, and frictional properties of the material. The deep draw process for a molten plastic sheet can be described by a simplified model using the characteristics of the normal stress as a lumped parameter. A rapid evaluation of the draw ratio and mold closing speed can be obtained by systematically drawing a series of three draw ratios. The fracture mode should then be examined to determine the appropriateness of molding temperatures. Therefore the maximum attainable draw ratio can be calculated from the elongational viscosity data. To support the analysis, data is provided on the formation of a cup with polystyrene sheets and using Maxwell extensional model as an example. |
