Several CAD programs and dedicated CAD translation services offer a way to convert SolidWorks part files (.sldprt) as common 3D objects (.obj), i.e. sldprt to obj conversion. Solidworks itself may offers export of its own CAD files to OBJ format, but it may require a special plugin in some earlier versions though.
Viable alternative would be to find and use some kind of 3rd party CAD / 3D model conversion software.