Use this procedure to turn on material definitions in a display representation if they are assigned to objects but are not displayed in the drawing. 
-  Click 

. 
   
- Expand Configurations. 
The current display configuration is marked in bold. 
  
- Expand the current display configuration. 
 
- Select a display set in the current display configuration. 
 
- Click the Display Representation Control tab. 
 
- Scroll to Material Definition and select a display representation. 
By default, material definitions have only a General display representation. If this is the only available display representation listed, select it. If you created another display representation for material definitions, you can select that representation instead. 
 Note: Make sure that you select only one display representation for material definitions in each display set. You should also verify that the component’s object layer is turned on. 
  
- Repeat steps 4–6 to select a display representation for material definitions in the other display sets in the current configuration. 
 
- Click OK. 
The material assignments you made now display in the drawing.