When creating renders in 3DS Max you might not necessarily create the geometry inside the software. One way to create the geometry is through Inventor and then import it using the import and merge functionality in 3DS Max.
The materials that Inventor uses is from the Autodesk library. this library is also shared between AutoCAD, Revit as well as 3DS Max.
What this allows the software to do is if you import or open any models between these 4 software packages the material will look the same and because the renderer that they us is the ART (Autodesk Raytrace Renderer) the models come out looking the same no matter which software package you render it in.
The difference with the ART renderer in 3DS Max is that it is quicker. The con to this is that the Autodesk materials are not the best to render. The ART renderer prefers physical materials. The default renderer for 3DS Max, Arnold, will not render Autodesk materials.
With this incompatibility you need to convert the Autodesk materials to Physical materials.
Physical materials are better for both the ART and Arnold renderer, which allows you to render faster and get a much higher quality render.
So to convert the materials , you grab the material that is assigned to the object and then change the Autodesk material to a Physical one.
Take note of the values of the RGB colour of the material coming from Inventor, as when you choose a preset in the Physical material it defaults to another colour.
Once you have chosen your preset you can insert the RGB values of your original material and tweak it some more to get your desired rendering result.
