Remember that the bullet is going somewhere and if it doesn't penetrate the plate there is a good chance of it ricocheting back to you.
No - at least not with the right plates.
I've shot, and supervised, approximately a gazillion rounds fired at steel plates and other steel targets.
Mild steel that becomes pitted, cratered, and penetrated like the photo in the top post will send bullet fragments back towards the shooter. It is imperative that if a plate is in this condition, it be used only a long way away from the shooter. These are the kinds of steel targets you're not supposed to use.
However, when a bullet impacts a hardened, armor steel plate with a trajectory normal to the surface of the plate (ie, perpendicular) it splatters on impact and the fragments splash in a disk parallel to the plate. Most action shooting sports mandate a 10 yard minimum distance to steel targets. Using proper armor steel targets and correct shoot and target position, the bullet isn't going anywhere-- it's getting disintegrated safely.