ABSTRACT
There is currently increasing commercial interest in developing models that are able to predict material response to such industrial processes as injection molding, extrusion, blow molding, etc. Apart from the subsequent flow-induced characteristics from such processes, changes in the material in going from the melt to the glassy state can lead to changes in material dimension and stability that differ from those estimated from a thermoelastic analysis [1,2]. Furthermore, even in the glassy state the material may still evolve with time, leading to significant changes in material properties. As the models needed to adequately describe this complex behavior get increasingly sophisticated, there is a corresponding need for reliable material data to successfully implement them. In response to this need, ongoing work in this laboratory [3,4] has been aimed at developing an efficient methodology that reduces both the experimental time and complexity required to obtain accurate material parameters. As part of this work, a systematic study of one industrially important polymer (the polycarbonate Lexan LS) supplied by the General Electric Company [5] that is currently being evaluated in the context of the Thermoplastic Engineering Design program [6] has been carried out under a range of loading conditions and geometries in order to build a
comprehensive material database. This can then be used in a critical evaluation of proposed models of material behavior.
