Never seen it, but a bit of metallurgical background can help. Cast iron is very hard, but brittle. Hit the handle with a hammer, and it will come off. Drop it on concrete, and it may snap off. Steel competition kettlebells, however, don't share this characteristic. Hit the handle with a sledgehammer, and the kettlebell will go flying across the room. It might bend or dent, but it won't break.
I dropped a cast iron 16k on my concrete garage floor once. It landed on the ball, and there is a dent in the floor. The handle is fine.
Under normal use on a soft surface, it's not likely.
Took one for the team this morning. Call it an experiment. Trying to work up strength to do hook grip with 24 kg bell for swings. Can do fine on 16 kg but 24 kg handle slightly bigger. After couple weeks loaded carries and really emphasizing hook with the 16kg am making definite progress but today it went flying mid set. Actually hit the 16 kg on the fly that was sitting about 8 feet away and good thing too or it likely would have gone into (and I do mean into) my apt wall. Not a scratch on either of them, zero, still both look new! Solid.