howto erase many links to material datablocks?

lets say I have a very complicated scene, which i imported and i want to keep just the mesh, position, rotation and the scale…i want to get rid of all materials linked to any object, how is this possable (not doing it one by one of course?)

ok, so now I cen pretty answer myself:)
in Outliner i choose the material datablock which i want to delete…then i do Shift+L (Users of selected) it selects the meshes, then Shift+L once again to select All object using these meshes…

then in context menu i did…CTRL+L make links …to material.
i hope i did get it all right…

Well, I just tested, and you should be able to make an object that has no material, select everything, make that new object active, and do the Object > Make Links > To Material, which is effectively a “copy from active to all other selected” thing that will copy the not-link from the new object to everything else. …

What I do, Open a New Blender file, append that object ( as Object) in the new file, Only active material links will come in the new file alongwith the object.