Both .sab and .sat files are CAD drawings from 3D ACIS Modeler and most likely can be converted or just simply re-saved with the original program. The key difference between these two format is that .sab files are in binary format, hence can be probably loaded faster.
Such sab to sat conversion might also be done using some dedicated 3D modeling / CAD converter, which is useful for users without access to 3D ACIS Modeler.Open SAB file Open SAT file
A 3D modeling engine used by many software developers
A dedicated CAD converter