I've been hit with a (blunt) steel sword. Many times actually, due to a hobby or something. But I can remember only one time when it hurt a lot. It hit me straight on the elbow. It hit the bone with a pretty high speed and it hurt on my whole arm for a couple of days. The elbow was so swollen for a while that I couldn't move my arm almost at all. The elbow was sore even long after a month. Didn't fence for a while.
I didn't know if it was broken or something, but I don't like doctors so I didn't go to see one. Now the arm's okay, though.
(And no, the swords weren't foils or any other used in that kind of fencing. We're talking about heavier, viking-style, wide bladed swords here. Actually, the sword I was hit with was exactly like
this one.)