.DXF file saved from inventor doesn't open in solidworks
Yes, but the result is typically a 2D sketch.
I think it really depends on what was designed, and how it was saved out.
Often what people describe to me as a "3D DXF" turns out to be noting more than an isometric view, exported as a 2D sketch.
Many years ago, I converted some true 3D DXF files out of AutoCAD with the ACIS (SAT) format, so they could be used in SolidWorks.