I want to bend aluminium rod (sharp angle bending)?

I would suggest that you bend it around a rounded corner. Use a pair of Vice-Grips clamped on to the bend point to hold the diameter.(Not a good solution, but that's all that comes to mind at the moment.)

If it's a hollow tube, it's easier: Find a strong coil spring - like a screen door spring - which fits inside - or outside - the tube. Side the spring down inside the tube, centered on the bend point.

Actually, this should work for the rod, also. Get a spring which JUST fits over the rod. Good luck!

Shiny. :-)