With the File | Export | Part Model | CAD Mesh menu option, you can export your CAD model as a lightweight mesh (as a .cad or .draw file). This export saves the model's surfaces as triangle meshes instead of the mathematical surface definitions. This essentially strips the model to its bare essentials that you can then use for visualization or collision detection. For a size comparison, after export a 2.9 MB .iges model file exported as a CAD mesh file takes up only 458 KB of space.
You may also find this menu option a useful solution to create a lightweight model for things like quick fixtures and other components.
A CAD mesh file is not an alternative for a true CAD model file. For example, with a mesh file, you lose the ability for PC-DMIS to use QuickFeatures or to do one-click Auto Feature selection.