I've seen a few vehicles with their plastic bumpers off recently. They all seem to have a large metal crossbar sitting in front of the radiator. What is this called?
Update:
And a sideview of the metal crossbar to impact absorber to chassis rail on an Audi A3.
That is your actual bumper
The bumper you have off is just a cover for your real bumper which is what you are describing.
That bumper, the real one, is tied to your frame and is actually absorbing the energy from impact where the facade is just existing as a cover due to the ugliness of the actual bumper.
This part is generally called the impact bar, or sometimes reinforcement bar or bumper reinforcer, and, along with the (often styrofoam, sometimes plastic, missing or hidden in your picture) absorber pad, serves the actual safety purpose of a modern bumper. The plastic piece is called the bumper cover.
The absorber pad is crushed to absorb energy in a crash, and the impact bar transmits force through the frame in order to stop the car rather than crushing the engine compartment.
Dependent on your country, I've heard this referred to as a chassis cross member (not so much anymore), bumper reinforcement bar and crash bar.
